absorb to take in, as nutrients are taken into the intestinal cells after digestion, the main function of the digestive tract with respect to nutrients.

acceptable daily intake (ADI) the estimated amount of sweetener that can be consumed daily over a person’s lifetime without any adverse effects.

accredited approved; in the case of medical centers or universities, certified by an agency recognized by the U.S. Department of Education.

acesulfame (AY-sul-fame) potassium, also called acesulfame-K a zero-calorie sweetener approved by the FDA.

acetaldehyde (ass-et-AL-deh-hide) a substance to which ethanol is metabolized on its way to becoming harmless waste products that can be excreted.

acid reducers and acid controllers drugs that reduce the acid output of the stomach. They are most suitable for treating severe, persistent forms of heartburn, but are useless for neutralizing acid already present in the stomach. Previously sold as prescription ulcer medications, the drugs are now sold freely, but the packages bear warnings of side effects; some types interfere with the stomach’s ability to destroy alcohol.

acidosis (acid-DOH-sis) blood acidity above normal, indicating excess acid (osis means "too much in the blood").

acids compounds that release hydrogen in a watery solution.

acid-base balance maintenance of the proper degree of acidity in each of the body’s fluids.

acne chronic inflammation of the skin’s follicles and oil-producing glands, which leads to an accumulation of oils inside the ducts that surround hairs; usually associated with the maturation of young adults.

added sugars sugars added to a food for any purpose, such as to add sweetness or bulk or to aid in browning (baked goods).

additives substances that are added to foods, but are not normally consumed by themselves as foods.

adequacy the dietary characteristic of providing all of the essential nutrients, fiber, and energy in amounts sufficient to maintain health and body weight.

aerobic (air-ROE-bic) requiring oxygen. Aerobic activity requires the heart and lungs to work harder than normal to deliver oxygen to the tissues, and therefore strengthens them.

agribusiness agriculture practiced on a massive scale by large corporations owning vast acreages and employing intensive technological, fuel, and chemical inputs.

AIDS acquired immune deficiency syndrome, caused by infection with HIV, a virus that is transmitted primarily by sexual contact, by contact with infected blood, by needles shared among drug users, or by materials transferred from infected mother to her fetus or infant.

alcohol debydrogenase (ADH) an enzyme system that breaks down alcohol. The antidiuretic hormone listed below is also abbreviated ADH.

alcoholism a dependency on alcohol marked by compulsive uncontrollable drinking with negative effects on physical health, family relationships, and social health.

alcohol-related birth defects see fetal alcohol syndrome

alimentary canal see digestive system.

alitame a noncaloric sweetener formed from the amino acid L-aspartic acid and L-alanine. In the United States, the FDA is considering its approval.

alkalosis (al-kah-LOH-sis) blood alkalinity above normal (‘ means "base"; osis means "too much in the blood").

allergy an immune reaction to a foreign substance, such as component of food. Also called hypersensitivity by researchers

aloe a tropical plant with widely claimed value as a topical treatment for minor skin injury. Some scientific evidence supports this claim; evidence against its use in severe wounds also exists.

alpha-lactalbumin (lact-AL-byoo-min) the chief protein in human breast milk. The chief protein in cow’s milk is casein (CAY-seen).

alternative (low-input, or sustainable) agriculture agriculture practiced on a small scale using individualized approaches that vary with local conditions so as to minimize technological, fuel, and chemical inputs.

amenorrhea the absence or cessation of menstruation.

American Dietetic Association (ADA) the professional organization of dietitians in the United States. The Canadian equivalent is the Dietitians of Canada (DC), which operates similarly.

amine group (a-MEEN) the nitrogen-containing portion of amino acid.

amino acids (a-MEEN-o) building blocks of protein. Each with an amine group at one end, an acid group at the other, and distinctive side chain.

amino acid chelates compounds of minerals (such as calcium) combined with amino acids in a form that favors their absorption. Absorption approximates that of calcium from milk.

amino acid pools amino acids dissolved in cellular fluid that provide cells with ready raw materials from which to build new proteins or other molecules.

amniotic sac (am-nee-OTT-ic) the "bag of water" in the uterus in which the fetus floats.

anabolic steroid hormones chemical messengers related to the male sex hormone, testosterone, that stimulate building up of body tissues. Anabolic means promoting growth; sterol refers to compounds chemically related to cholesterol.

anaerobic (AN-air-ROE-bic) not requiring oxygen. Anaerobic activity may require strength but does not work the heart and lungs very hard for a sustained period.

anaphylactic shock (an-AFF-ill-LAC-tic) a life-threatening whole-body allergic reaction to an offending substance.

anecdotal evidence information based on interesting and entertaining, but not scientific, personal accounts of events.

anencephaly (an-en-SEFF-ah-lee) a severe neural tube defect that causes the brain not to form and leads to death soon after birth.

aneurysm (AN-you-rlsm) the ballooning out of an artery wall at a point that is weakened by deterioration.

anorexia nervosa an eating disorder characterized by a refusal to maintain a minimally normal body weight, self-starvation to the extreme, and a disturbed perception of body weight and shape; seen (usually) in teenage girls and young women (anorexia means "without appetite"; nerves means "of nervous origin").

antacids medications that react directly and immediately with the acid of the stomach, neutralizing it. Antacids are most suitable for treating occasional heartburn. Some preparations (such as Tums) contain the mineral calcium, but others do not.

antibodies (AN-tee-bod-ees) large proteins of the blood, produced by the immune system in response to invasion of the body by foreign substances (antigens). Antibodies combine with and inactivate the antigens.

antidiuretic hormone (ADH) a hormone produced by the pituitary gland in response to dehydration (or a high sodium concentration in the blood). It stimulates the kidneys to reabsorb more water and so to excrete less. (This hormone should not be confused with alcohol dehydrogenase, which is also abbreviated ADH.)

antigen a substance foreign to the body that elicits the formation of antibodies or an inflammation reaction from immune system cells. Food antigens are usually glycoproteins (large proteins with glucose molecules attached). Inflammation consists of local swelling and irritation and attracts white blood cells to the site.

antimicrobial agents preservatives that prevent spoilage by mold or bacterial growth. Familiar examples are acetic acid (vinegar) and sodium chloride (salt). Others are benzoic, propionic, and sorbic acids; nitrites and nitrates; and sulfur dioxide.

antioxidant (anti-OX-ih-dant) a compound that protects other compounds from oxygen by itself reacting with oxygen (anti means "against"; oxv means "oxygen").

antioxidants preservatives that prevent rancidity of fats in foods and other damage to food caused by oxygen. Examples are vitamins E and C, BHA, BHT, propyl gallate, and sulfites.

antipromoters compounds in foods that act in several ways to oppose the formation of cancer.

antisense gene the chemical opposite of a gene, which adheres to the native working gene and keeps it from producing proteins.

aorta (ay-OR-tuh) the large, primary artery that conducts blood from the heart to the body’s smaller arteries.

Apgar score a system of scoring an infant’s physical condition right after birth. Heart rate, respiration, muscle tone, response to stimuli, and color are ranked 0,1, or 2. A low score indicates that medical attention is required to facilitate survival.

appendicitis inflammation and/or infection of the appendix, a sac protruding from the intestine.

appetite the psychological desire to eat; a learned motivation and a positive sensation that accompanies the sight, smell, or thought of appealing foods.

aquifers underground rock formations containing water that can be drawn to the surface for use.

arousal heightened activity of certain brain centers associated with attention, excitement, and anxiety.

arteries blood vessels that carry blood containing fresh oxygen supplies from the heart to the tissues.

artesian water water drawn from a well that taps a confined aquifer in which the water is under pressue.

arthritis a usually painful inflammation of joints caused by many conditions, including infections, metabolic disturbances, or injury; usually results in altered joint structure and loss of function.

artificial colors certified food colors, added to enhance appearance. (Certified means approved by the FDA). Vegetable dyes are extracted from vegetables such as beta-carotene from carrots. Food colors are a mix of vegetable dyes and synthetic dyes approved by the FDA for use in food.

artificial fats zero-energy fat replacers that are chemically synthesized to mimic the sensory and cooking qualities of naturally occurring fats, but are totally or partially resistant to digestion. Also called fat analogues.

artificial flavors, flavor enhancer chemicals that mimic natural flavors and those that enhance flavor.

ascorbic acid one of the active forms of vitamin C (the other is dehydroascorbic acid); an antioxidant nutrient.

aspartame a compound of phenylalanine and aspartic acid that tastes like the sugar sucrose but is much sweeter. It is used in both the United States and Canada.

atherosclerosis (ath-er-oh-scler-OH-sis) the most common form of cardiovascular disease, characterized by plaques along the inner walls of the arteries (athero means "porridge" or "soft"; scleros means "hard"; osis means "too much"). The related term arteriosclerosis refers to all forms of hardening of the arteries and includes some rare diseases.

atrophy (AT-fro-fee) a decrease in size of a muscle because of disuse.

attention deficit disorder see hyperactivity.

average a mathematical point found by adding a series of values and then dividing by the number of those values; also called the mean.

balance study a laboratory study in which a person is fed a controlled diet and the intake and excretion of a nutrient are measured. Balance studies are valid only for nutrients like calcium (chemical elements) that do not change while they are in the body.

balance the dietary characteristic of providing foods of a number of types in proportion to each other, such that foods rich in some nutrients do not crowd out of the diet foods that are rich in other nutrients. Also called proportionality.

basal metabolic rate (BMR) the rate at which the body uses energy to support its basal metabolism.

basal metabolism the sum total of all the involuntary activities that are necessary to sustain life, including circulation respiration, temperature maintenance, hormone secretion, nerve activity, and new tissue synthesis, but excluding digestion and voluntary activities. Basal metabolism is the largest component of the average person’s daily energy expenditure.

bases compounds that accept hydrogen from solutions.

basic foods milk and milk products; meats and similar foods such as fish and poultry; vegetables, including dried beans and peas; fruits; and grains. These foods are generally considered to form the basis of a nutritious diet. Also called whole foods.

bee pollen a product consisting of bee saliva, plant nectar, and pollen that confers no benefit on athletes and may cause an allergic reaction in individuals sensitive to it.

beer belly central body fatness associated with alcohol consumption.

behavior modification alteration of behavior using methods based on the theory that actions can be controlled by manipulating the environmental factors that cue, or trigger, the actions.

belladonna any part of the deadly nightshade plant; a fatal poison.

beriberi the thiamin-deficiency disease; characterized by loss of sensation in the hands and feet, muscular weakness, advancing paralysis, and abnormal heart action.

beta-carotene an orange pigment with antioxidant activity, a vitamin A precursor made by plants and stored in human fat tissue.

bicarbonate a common alkaline chemical; a secretion of the pancreas; also, the active ingredient of baking soda.

bile an emulsifier made by the liver from cholesterol and stored in the gallbladder. Bile does not digest fat as enzymes do but emulsifies it so that enzymes in the watery fluids may contact it and split the fatty acids from their glycerol for absorption.

binge eating disorder a new eating disorder whose criteria are similar to those of bulimia nervosa, excluding purging or other compensatory behaviors.

bioaccumulation the accumulation of a contaminant in the tissues of living things at higher and higher concentrations along the food chain.

bioavailability absorbability; the individual differences in the proportion of a nutrient that is available for absorption from various sources.

bioelectrical impedance a technique to measure body fatness by measuring the body’s electrical conductivity.

biosensor a genetically altered microbe that provides a rapid, low-cost, and accurate test for toxic products of microbial agents in foods.

biotechnology the science that manipulates biological systems or organisms to modify their products or components or create new products. See also genetic engineering.

biotin (BY-o-tin) a B vitamin; a coenzyme necessary for fat synthesis and other metabolic reactions.

bladder the sac that holds urine until time for elimination.

bleaching agents substances used to whiten foods such as flour and cheese. Peroxides are examples.

blood the fluid of the cardiovascular system, composed of water, red and white blood cells, other formed particles, nutrients, oxygen, and other constituents.

blood-brain barrier a barrier composed of the cells lining the blood vessels in the brain. These cells are so tightly glued to each other that blood-borne substances cannot get into the brain between the cells, but only by crossing the cell bodies themselves. Thus the cells, using all their sophisticated equipment, can screen substances for entry.

body composition the proportions of muscle, bone, fat, and other tissue that make up a person’s total body weight.

body mass index (BMI) an indicator of obesity, calculated by dividing the weight of a person by the square of the person’s height.

body system a group of related organs that work together to perform a function. Examples are the circulatory system, respiratory system, and nervous system.

bone density a measure of bone strength; the degree of mineralization of the bone matrix.

bone meal, powdered bone crushed or ground bone preparations intended to supply calcium to the diet, but not well absorbed and often contaminated with toxic materials.

boron a nonessential mineral that is promoted as a "natural" steroid replacement.

bottled water drinking water sold in bottles.

botulism an often-fatal food poisoning caused by botulinum toxin, a toxin produced by the Clostridium botulinum bacterium that grows without oxygen in nonacidic canned foods.

bovine somatotropin (BST) growth hormone of cattle, which can be produced for agricultural use by genetic engineering. Also called bovine growth hormone (BGH).

bran the protective fibrous coating around a grain; the chief fiber donator of a grain.

branched-chain amino acids amino acids that, unlike the others, can provide energy directly to muscle tissue: leucine, isoleucine, and valine.

brewer’s yeast see nutritional yeast.

brown fat adipose tissue abundant in hibernating animals and human infants. Brown fat cells are packed with pigmented, energy-burning enzymes that release heat rather than manufacturing fuels from fat. These enzymes give the cells a darkened appearance under a microscope.

brown sugar white sugar with molasses added, 95% pure sucrose.

buffers molecules that can help to keep the pH of a solution from changing by gathering or releasing H ions.

bulimia (byoo-LEEM-ee-uh) nervosa recurring episodes of binge eating combined with a morbid fear of becoming fat; usually followed by self-induced vomiting or purging.

caffeine a stimulant that in small amounts may produce alertness and reduced reaction time in some people, but that also creates fluid losses. Overdoses cause headaches, trembling, an abnormally fast heart rate, and other undesirable effects.

calcium citrate a calcium salt reported to have high absorbability. Other absorbable forms are calcium malate and calcium phosphate dibasic.

calcium pangamate a compound once thought to enhance aerobic metabolism, but now known to have no such effect.

calorie control control of energy intake. A feature of a sound diet plan.

calorie free as used on a food label, fewer than 5 calories per serving.

calories units of energy. Strictly speaking, the unit used to measure the energy in food is a kilocalorie (kcalorie, or Calorie): it is the amount of heat energy necessary to raise the temperature of a kilogram (a liter) of water 1 degree Celsius. This book follows the common practice of using the lowercase term calorie (abbreviated cal) to mean the same thing.

cancer a disease in which cells multiply out of control and disrupt normal functioning of one or more organs.

canning preservation by killing all microorganisms present in food and by then sealing out air. The food, container, and lid are heated until sterile; as the food cools, the lid makes an air tight seal, preventing contamination.

capillaries minute, web-like blood vessels that connect arteries to veins and permit transfer of materials between blood and tissues.

carbohydrate loading a regimen of performing exhausting exercise, followed by eating a high-carbohydrate diet, that

enables muscles to store glycogen beyond their normal capacity; also called glycogen loading or glycogen upercompensation.

carbohydrate sweeteners ingredients composed of carbohydrates that contain sugars used for sweetening food products, including glucose, fructose, corn syrup, concentrated grape juice, and other sweet carbohydrates.

carbohydrates compounds composed of single or multiple sugars. The name means "carbon and water," and a chemical shorthand for carbohydrate is CHO, signifying carbon (C), hydrogen (H), and oxygen (O).

carbonated water water that contains carbon dioxide gas, either naturally occurring or added, that bubbles from it; also called bubbling or sparkling water. Seltzer, soda, or tonic waters are legally soft drinks and are not regulated as water.

carcinogen (car-SIN-oh-jen) a cancer-causing substance (carcin means "cancer"; gen means "gives rise to").

cardiac output the volume of blood discharged by the heart each minute.

cardiovascular disease (CVD) disease of the heart and blood vessels, also called coronary heart disease. The two most common forms of CVD are atherosclerosis and hypertension.

cardiovascular endurance the ability of the lungs and cardiovascular system to sustain effort over a period of time.

carnitine a nitrogen-containing compound formed in the body from glutamine and methionine that helps transport fatty acids across the mitochrondrial membrane. Carnitine supposedly "burns" fat and spares glycogen during endurance events, but it does neither.

carrying capacity the total number of living organisms that a given environment can support without deteriorating in quality.

case studies studies of individuals, usually in clinical settings where researchers can observe treatments and their apparent effects. To prove that a treatment has produced an effect requires simultaneous observation of an untreated similar subject (a case control).

casein or sodium caseinate the principal protein of cow’s milk. Another milk protein, found in human milk’s whey is lactalbumin.

cash crops crops grown for sale or export, as opposed to food crops grown for local consumption.

cat’s claw an herb from the rain forests of Brazil and Peru, claimed, but not proved, to be an "all-purpose" remedy.

cataracts (CAT-uh-racts) thickening of the lens of the eye that can lead to blindness. Cataracts can be caused by injury, viral infection, toxic substances, genetic disorders. and possibly by some nutrient deficiencies or imbalances.

catecholamines neurotransmitters made from the amino acid tyrosine: dopamine, epinephrine, and norepinephrine.

cathartic a strong laxative.

CDC (Centers for Disease Control and Prevention) a branch of the Department of Health and Human Services that is responsible, among other things, for monitoring food-borne diseases.

cell salts a mineral preparation supposedly prepared from living cells.

cells the smallest units in which independent life can exist. All living things are single cells or organisms made of cells.

central obesity excess fat in the abdomen and around the trunk.

certified lactation consultant a health-care provider, often a registered nurse, with specialized training in breast and infant anatomy and physiology who teaches the mechanics of breast feeding to new mothers. Certification is granted after passing a standardized post-training examination.

chamomile flowers that may provide some limited medical value in soothing menstrual, intestinal, and stomach discomforts.

chaparral an herbal product made from ground leaves of the creosote bush, and sold in tea or capsule form; supposedly, this herb has antioxidant effects, delays aging, "cleanses" the bloodstream, and treats certain skin conditions—all unproven claims. Chaparral has been found to cause acute toxic hepatitis, a severe liver illness.

chelating agents (KEE-late-ing) molecules that surround other molecules and are therefore useful in either preventing or promoting movement of substances from place to place. As food additives, they prevent discoloration, flavor changes, and rancidity that might occur because of processing. Examples are citric acid, malic acid, and tartaric acid (cream of tartar).

chlorophyll the green pigment of plants that captures energy from sunlight for use in photosynthesis.

Chinese restaurant syndrome see MSG symptom complex.

cholesterol (koh-LESS-ter-all) a member of the group of lipids known as sterols; a soft waxy substance manufactured in the body for a variety of purposes and also found in animal derived foods.

cholesterol free on a food label, less than 2 mg cholesterol and 2 g or less saturated fat per serving.

choline (KOH-leen) a nonessential nutrient used to make the phospholipid lecithin and other molecules.

chromium picolinate a trace element supplement; falsely promoted to increase lean body mass, enhance energy, and burn fat.

chronic disease long-duration degenerative diseases characterized by deterioration of the body organs; examples include heart disease, cancer, and diabetes. Also called degenerative disease or lifestyle disease.

chylomicrons (KYE-low-MY-krons) clusters formed when lipids from a meal are combined with carrier proteins in the intestinal lining. Chylomicrons transport food fats through the watery body fluids to the liver and other tissues.

chyme (KIME) the fluid resulting from the actions of the stomach upon a meal.

cirrhosis (seer-OH-sis) advanced liver disease, often associated with alcoholism, in which liver cells have died, hardened, turned an orange color, and permanently lost their function.

coenzyme (co-EN-zime) a small molecule that works with an enzyme to promote the enzyme’s activity. Many coenzymes have B vitamins as part of their structure (co means "with").

coenzyme Q10 a lipid found in cells (mitochondria) that has been shown to improve exercise performance in heart disease patients, but is not effective in improving performance of healthy athletes.

collagen (COLL-ajen) the chief protein of most connective tissues, including scars, ligaments, and tendons, and the underlying matrix on which bones and teeth are built.

colon the large intestine.

colostrum ( co- LA HS-trum) a milk-like secretion from the breast during the first day or so after delivery before milk appears; rich in protective factors.

comfrey leaves and roots of the comfrey plant; believed, but not proved, to have drug effects. Comfrey contains cancer causing chemicals.

complementary proteins two or more proteins whose amino acid assortments complement each other in such a way that the essential amino acids missing from each are supplied by the other.

complete proteins proteins containing all the essential amino acids in the right balance to most human needs.

complex carbohydrates long chains of sugar units arranged to form starch or fiber; also called polysaccharides.

concentrated fruit juice sweetener a concentrated sugar syrup made from dehydrated, deflavored fruit juice, commonly grape juice; used to sweeten products that can then claim to be "all fruit."

condensed milk evaporated milk to which a large amount of sugar (sucrose) is added during processing; intended for making desserts, not for feeding babies. Accidental use of condensed milk in preparation of infant formula can cause dehydration.

confectioner’s sugar finely powdered sucrose, 99.9% pure.

congeners (CON-jen-ers) chemical substances other than alcohol that account for some of the physiological effects of alcoholic beverages, such as taste and aftereffects.

constipation hardness and dryness of bowel movements, associated with discomfort in passing them from the body.

contaminant any substance occurring in food by accident; any food constituent that is not normally present.

control group a group of individuals who are similar in all possible respects to the group being treated in an experiment but who receive a sham treatment instead of the real one. Also called control subjects. See also intervention studies.

corn sweeteners corn syrup and sugar solutions derived from corn.

corn syrup a syrup, mostly glucose, partly maltose, produced by the action of enzymes on cornstarch. High-fructose corn syrup (HFCS) is mostly fructose; glucose (dextrose) and maltose make up the balance.

cornea (KOR-nee-uh) the hard, transparent membrane covering the outside of the eye.

correlation the simultaneous change of two factors, such as the increase of weight with increasing height (a direct or positive correlation) or the decrease of cancer incidence with increasing fiber intake (an inverse or negative correlation). A correlation between two factors suggests that one may cause the other, but does not rule out the possibility that both may be caused by a third factor. If the latter case turns out to be true, then the correlation is coincidental.

Correspondence school a school that offers courses and degrees by mail. Some correspondence schools are accredited; others are diploma mills.

cortex the outermost layer of something. The brain’s cortex is the part of the brain where conscious thought takes place.

cortical bone the ivorylike outer bone layer that forms a shell surrounding trabecular bone and that comprises the shaft of a long bone.

creatine a nitrogen-containing compound that combines with phosphate to burn a high-energy compound stored in muscle. Claims that creatine enhances energy and stimulates muscle growth need further confirmation.

cretinism (CREE-tin-ism) severe mental and physical retardation of an infant caused by the mother’s iodine deficiency during her pregnancy.

critical period a finite period during development in which certain events may occur that will have irreversible effects on later developmental stages. A critical period is usually a period of cell division in a body organ.

cruciferous vegetables vegetables with cross-shaped blossoms. Their intake is associated with low cancer rates in human populations. Examples are cauliflower, cabbage, brussels sprouts, broccoli, turnips, and rutabagas.

cuisine a style of cooking.

cyclamate a zero-calorie sweetener under consideration for use in the United States and used with restrictions in Canada.

Daily Values a set of nutrient intake standards designed for use on U.S. food labels.

degenerative disease chronic, irreversible disease characterized by degeneration of body organs due in part to such personal lifestyle elements as poor food choices, smoking, alcohol use, and lack of physical activity. Also called lifestyle diseases, chronic diseases, or the disease of old age.

dehydration loss of water. The symptoms progress rapidly, from thirst to weakness to exhaustion and delirium, and end in death.

denaturation the change in shape of a protein brought about by heat, acids, bases, alcohol, salts of heavy metals, or other agents.

dental caries decay of the teeth (caries means "rottenness").

desiccated liver a powder sold in health-food stores and supposed to contain in concentrated form all the nutrients found in liver. Possibly not dangerous, this supplement has no particular nutritional merit, and grocery store liver is considerably less expensive (desiccated means "totally dried").

dextrose an older name for glucose.

DHEA a hormone secretion of the adrenal gland whose level falls with advancing age. DHEA may protect antioxidant nutrients; low blood levels are associated with elevated risk of diseases. Theories that DHEA might stimulate hormone responsive cancers such as breast or prostate are unproved.

diabetes (dye-uh-BEET-eez) a disease (technically termed diabetes mellitus) characterized by inadequate or ineffective insulin, which renders a person unable to regulate blood glucose normally. In Type I diabetes (also called juvenile-onset, or insulin-dependent diabetes) the pancreas produces no insulin; in Type II diabetes (also called adult-onset or noninsulin-dependent diabetes) the pancreas makes insulin, but the fat cells are resistant to its effects.

diarrhea frequent, watery bowel movements usually caused by diet, stress, or irritation of the colon. Severe, prolonged diarrhea robs the body of fluid and certain minerals, causing dehydration and imbalances that can be dangerous if left untreated.

diastolic pressure (dye-as-TOL-ik) the second figure ina blood pressure reading (the "lub" of the heartbeat), which reflects the arterial pressure when the heart is between beats.

diet the foods (including beverages) a person usually eats and drinks.

dietary supplement a product, other than tobacco, added to the diet that contains one of the following ingredients: a vitamin, mineral, herb, botanical (plant extract), amino acid, metabolite, constituent, extract, or combination of any of these ingredients.

diet-induced thermogenesis see thermic effect of food.

dietitian a person trained in nutrition, food science, and diet planning. See also registered dietitian.

digest to break molecules into smaller molecules, a main function of the digestive tract with respect to food.

digestive system the body system composed of organs that break down complex food particles into smaller, absorbable products. The digestive tract and alimentary canal are names for the tubular organs that extend from the mouth to the anus. The whole system, including the pancreas, liver, and gallbladder, is sometimes called the gastrointestinal, or GI system.

dipeptides (dye-PEP-tides): protein fragments that are two amino acids long. A peptide is a strand of amino acids (di means "two").

diploma mill an organization that awards meaningless degrees without requiring its students to meet educational standards.

disaccharides pairs of single sugars linked together (di means "two").

distilled water water that has been vaporized and recondensed, leaving it free of dissolved minerals.

diuretics (dye-you-RET-ics) compounds, usually medications, causing increased urinary water excretion; "water pills".

diverticulosis (dye-ver-tic-you-LOH-sis) outpocketing or ballooning out of areas of the intestinal wall, caused by weakening of the muscle layers that encase the intestine.

DNA and RNA (deoxyribonucleic acid and ribonucleic acid) the genetic materials of cells necessary in protein synthesis; falsely promoted as ergogenic aids.

dolomite a compound of minerals (calcium magnesium carbonate) found in limestone and marble. Dolomite is powdered and is sold as a calcium-magnesium supplement, but may be contaminated with toxic minerals such as arsenic, cadmium, mercury, and lead and is not well absorbed.

drink a dose of any alcoholic beverage that delivers 1 ounce of pure ethanol.

drying preservation by removing sufficient water from food to inhibit microbial growth.

dysentery (DISS-en-terry) an infection of the digestive tract that causes diarrhea.

eating disorder a disturbance in eating behavior that jeopardizes a person’s physical or psychological health.

echinacea an herb popular before the advent of antibiotics for its assumed "anti-infectious" properties and as an all-purpose remedy, especially for colds and allergy and for healing of wounds. A small body of research from the 1970s seems to lend preliminary support for some of the claims, but also pointed to an insecticidal property, leading to questions about its safety. Also called cone-flower.

edema (eh-DEEM-uh) swelling of body tissue caused by leakage of fluid from the blood vessels, seen in (among other conditions) protein deficiency.

electrolytes compounds that partly dissociate in water to form ions, such as the potassium ion (K+) and the chloride ion (Cl- ).

electron part of an atom; a negatively charged particle. Stable atoms (and molecules, which are made of atoms) have even numbers of electrons in pairs. An atom or molecule with an unpaird electron is a free radical.

elemental calcium a term on supplement labels referring to the amount of calcium present among other constituents. For example, an antacid may contain 1,200 milligrams of calcium carbonate, but just 500 milligrams of calcium itself; the rest is made up of carbonate.

elemental diets diets composed of purified ingredients of known chemical composition; intended to supply all essential nutrients to people who cannot eat foods.

embolism an embolus that causes sudden closure of a blood vessel.

embolus (EM-boh-luss) a thrombus that breaks loose (embol means "to insert").

embryo (EM-bree-oh) the stage of human gestation from the third to eighth week after conception.

emetic (em-ETT-ic) an agent that causes vomiting.

emulsification the process of mixing lipid with water, by adding an emulsifier.

emulsifier a substance that mixes with both fat and water and permanently disperses fat in water, forming an emulsion.

endogenous opiates, endorphins compounds made in the brain whose actions mimic those of opiate drugs (morphine, heroin) in reducing pain and producing pleasure.

endosperm the bulk of the edible part of a grain, the starchy part.

energy the capacity to do work. The energy in food is chemical energy; it can be converted to mechanical, electrical, heat, or other forms of energy in the body. Food energy is measured in calories.

energy-yielding nutrients the nutrients the body can use for energy They may also supply building blocks for body structures.

enriched foods and fortified foods foods to which nutrients have been added. If the starting material is a whole, basic food such as milk or whole grain, the result may be highly nutritious. If the starting material is a concentrated form of sugar or fat, the result may be less nutritious.

enriched, fortified refers to addition of nutrients to a refined food product. As defined by U.S. law, this term means that specified levels of thiamin, riboflavin, niacin, folate and iron have been added to refined grains and grain products. The terms enriched and fortified can refer to addition of more nutrients than just these five; read the label. Formerly, enriched and fortified carried distinct meanings with regard to the nutrient amounts added to foods. But a change in the law has made these terms virtually synonymous.

entertoxins poisons that act upon mucous membranes, such as those of the digestive tract.

enzymes (EN-zimes) protein catalysts. A catalyst is a compound that facilitates a chemical reaction without itself being altered in the process.

EPA (Environmental Protection Agency) a federal agency that is responsible, among other things, for regulating pesticides and establishing water quality standards.

EPA, DHA eicosapentaenoic acid, docosahexaenoic acid; omega-3 fatty acids made from linolenic acid in the tissues of fish.

ephedrine One of a chemically-related group of compounds with dangerous amphetamine-like stimulant effects; commonly added to herbal preparations such as Ma huang, to weight-loss products, and to products claimed to imitate the effects of illegal drugs of abuse. Dangerous side effects are likely, especially when ephedrine is combined with caffeine.

epidemiological studies studies of populations; often used in nutrition to search for correlations between dietary habits and disease incidence; a first step in seeking nutrition-related causes of diseases.

epinephrine the major hormone that elicits the stress response.

epithelial tissue (ep-ih-THEE-lee-ull) the layers of the body that serve as selective barriers to environmental factors. Examples are the cornea, the skin, the respiratory lining, and the lining of the digestive tract.

ergogenic the term implies "energy giving," but, in fact, no products impart such a quality (ergo means "work"; genic means "gives rise to").

erythrocyte (eh-REETH-ro-sight) hemolysis (he-MOLL-ih-sis) rupture of the red blood cells, caused by vitamin E deficiency (erythro means "red"; cyte means "cell"; hemo means "blood"; Iysis means "breaking").

essential amino acids amino acids that either cannot be synthesized at all by the body or cannot be synthesized in amounts sufficient to meet physiological need. Also called indispensable amino acids.

essential fatty acids fatty acids that the body needs but can not make in amounts sufficient to meet physiological needs.

essential nutrients the nutrients the body cannot make for itself (or cannot make fast enough) from other raw materials; nutrients that must be obtained from food to prevent deficiencies.

ethanol the alcohol of alcoholic beverages, produced by the action of microorganisms on the carbohydrates of grape juice or other carbohydrate-containing fluids.

ethnic foods foods associated with particular cultural subgroups within a population.

euphoria an inflated sense of well-being and pleasure brought on by a moderate dose of alcohol and some other drugs.

evaporated milk formula formula made at home from evaporated milk, sugar, and water, seldom used today and not recommended.

evaporated milk milk concentrated to half volume by evaporation. Adding water reconstitutes the milk; the taste is altered by the processing, however.

exchange system a diet planning tool that organizes foods with respect to their nutrient contents and calorie amounts. Foods on any single exchange list can be used interchangeably. See the Exchange System, Appendix D for details.

experimental group the people or animals participating in an experiment who receive the treatment under investigation. Also called experimental subjects. See also intervention studies.

externalities hidden costs that are not reflected in the prices of things, such as the costs of subsidies that permit agribusiness foods to be sold at artificially low prices.

extra lean on a food label, less than 5 g of fat, less than 2 g of saturated fat, and less than 95 mg of cholesterol per serving.

extracellular fluid fluid residing outside the cells.

extrusion a process by which the form of food is changed, such as changing corn to corn chips.

famine widespread scarcity of food in an area that causes starvation and death in a large portion of the population.

fast foods restaurant foods that are available within minutes after customers order them—traditionally, hamburgers, french fries, and milkshakes; more recently, salads and other vegetable dishes as well. These foods may or may not meet people's nutrient needs well, depending on the selections made and on the energy allowances and nutrient needs of the eaters.

fasting hypoglycemia hypoglycemia that occurs after 8 to 14 hours of fasting.

fat cells cells that specialize in the storage of fat and that form the fat tissue.

fat free less than 0.5 g of fat per serving.

fat replacer any substance added to a food that replaces some or all of the fat in the food.

fatfold test measurement of the thickness of a fold of skin on the back of the arm (over the triceps muscle), below the shoulder blade (subscapular), or in other places, using a caliper. Also called skinfold test.

fats lipids that are solid at room temperature (70°F or 250C).

fatty acids organic acids composed of carbon chains of various lengths. Each fatty acid has an acid end and hydrogens attached to all of the carbon atoms of the chain.

fatty liver an early stage of liver deterioration seen in several diseases, including kwashiorkor and alcoholic liver disease in which fat accumulates in the liver cells.

FDA (Food and Drug Administration) a part of the Department of Health and Human Services' Public Health Service that is responsible for ensuring the safety and wholesomeness of all foods sold in interstate commerce except meat, poultry, and eggs (which are under the jurisdiction of the USDA); inspecting food plants and imported foods; and setting standards for food consumption.

feces waste material remaining after digestion and absorption are complete; eventually discharged from the body.

female athlete triad a potentially fatal triad of medical problems seen in women athletes: disordered eating, amenorrhea, and osteoporosis.

fetal alcohol effect (FAE) partial abnormalities from prenatal alcohol exposure, not sufficient for diagnosis with FAS, but impairing to the child. Also called alcohol-related birth defects (ARBD) or subclinical FAS.

fetal alcohol syndrome (FAS) the cluster of symptoms seen in an infant or child whose mother consumed excess alcohol during her pregnancy. FAS includes, but is not limited to, brain damage, growth retardation, mental retardation, and facial abnormalities.

fetus (FEET-us) the stage of human gestation from eight weeks after conception until birth of an infant.

feverfew an herb sold as a migraine headache preventive. Some evidence exists to support this claim.

fibers the indigestible polysaccharides in food, comprised mostly of cellulose, hemicellulose, and pectin. Also called non starch polysaccharides.

fibrosis (fye-BROH-sis) an intermediate stage of alcoholic liver deterioration in which liver cells lose their function and assume the characteristics of connective tissue cells (fibers).

fight-or-flight reaction the body's instinctive hormone- and nerve-mediated reaction to danger. Also known as the stress response.

filtered water water treated by filtration, usually through activated carbon filters that reduce the lead in tap water, or by reverse osmosis units that force pressurized water across a membrane removing lead, arsenic, and some microorganisms from tap water.

flexibility the capacity of the joints to move through a full range of motion; the ability to bend and recover without injury.

fluid and electrolyte balance maintenance of the proper amounts and kinds of fluids and minerals in each compartment of the body.

fluid and electrolyte imbalance failure to maintain the proper amount and kind of fluid in every body compartment; a medical emergency.

fluorapatite (floor-APP-uh-tight) a crystal of bones and teeth, formed when fluoride displaces the hydroxy portion of hydroxyapatite. Fluorapatite resists being dissolved back into body fluid.

fluorosis (floor-OH-sis) discoloration of the teeth due to ingestion of too much fluoride during tooth development.

folate (FOH-late) a B vitamin that acts as part of a coenzyme important in the manufacture of new cells. Other names for folate are folacin and folic acid.

food medically, any substance that the body can take in and assimilate that will enable it to stay alive and to grow; the carrier of nourishment; socially, a more limited number of such substances defined as acceptable by each culture.

food aversion an intense dislike of a food, possibly biological in nature, resulting from an illness or other negative experience associated with that food.

food group plans diet planning tools that sort foods into groups based on origin and nutrient content and then specify that people should eat certain minimum numbers of servings of foods from each group.

food insecurity the condition of uncertain access to food of sufficient quality or quantity.

food intolerance an adverse effect of a food or food additive not involving the immune response.

food poisoning illness transmitted to human beings through food; caused by a poisonous substance (food intoxication) or an infectious agent (food-borne infection). Also called food-borne illness.

food poverty hunger occurring when enough food exists in an area but some of the people cannot obtain it because they lack money, they are being deprived for political reasons, they live in a country at war, or because of other problems such as lack of transportation.

food shortage hunger occurring when an area of the world lacks enough total food to feed its people.

foodways the sum of a culture's habits, customs, beliefs, and preferences concerning food.

formaldehyde a substance to which methanol is metabolized on the way to being converted to harmless waste products that can be excreted.

fortified (with respect to milk) milk to which vitamins A and D have been added.

fossil fuel coal, oil, and natural gas. These are nonrenewable fuels that pollute. Renewable or alternative fuels, such as solar and wind energy, pollute less or not at all.

foxglove a plant that contains a substance used in the heart medicine digoxin.

fraud or quackery the promotion, for financial gain, of devices, treatments, services, plans, or products (including diets and supplements) that alter or claim to alter a human condition without proof of safety or effectiveness. (The word quackery comes from the term quacksalver, meaning a person who quacks loudly about a miracle product—a lotion or a salve.)

free radical an atom or molecule with one or more unpaired electrons that make it unstable and highly reactive.

free, without, no, zero on a food label, none or a trivial amount. Calorie free means containing fewer than 5 calories per serving; sugar free or fat free means containing less than half a gram per serving.

freezing preservation by lowering food temperature to a point that halts life processes. Microorganisms do not die but remain dormant until the food is thawed.

fresh raw, unprocessed or minimally processed with no added preservatives.

fructose (FROOK-tose) a monosaccharide; sometimes known as fruit sugar (fruct means "fruit"; ose means "sugar"), fructose, galactose, glucose the monosaccharides.

fruitarian includes only raw or dried fruits, seeds, and nuts.

galactose (ga-LACK-tose) a monosaccharide; part of the disaccharide lactose (milk sugar).

garlic oil an extract of garlic; may or may not contain the chemicals associated with garlic; claims for health benefits unproved.

gastric bypass surgery that reroutes food from the stomach to the lower part of the small intestine, creating a chronic, life long state of malabsorption by preventing normal digestion and absorption of nutrients.

gastric juice the digestive secretion of the stomach.

gastrointestinal tract see digestive system.

gastroplasty surgery involving partitioning of the stomach by stapling off a "pouch" or otherwise constricting the volume of food the stomach can accept at a meal and thereby reducing total food intake.

gatekeeper with respect to nutrition, a key person who controls other people's access to foods and thereby affects their nutrition profoundly. Examples are the spouse who buys and cooks the food, the parent who feeds the children, and the caretaker in a day-care center.

genes units of a cell's inheritance, made of the chemical DNA (deoxyribonucleic acid). Each gene directs the making of a protein to do the body's work.

genetic engineering a field within biotechnology that involves the direct, intentional manipulation of the genetic material of living things in order to obtain some desirable trait not present in the original organism; also called recombinant DNA technology.

germ in reference to whole grains, the nutrient-rich inner part of a grain.

gestation the period of about 40 weeks (three trimesters) from conception to birth; the term of a pregnancy.

gestational diabetes abnormal glucose tolerance appearing during pregnancy, with subsequent return to normal after the end of pregnancy.

ginkgo biloba an extract of a tree of the same name, claimed to enhance mental alertness, but not proved to be effective or safe.

ginseng (JIN-seng) a plant containing chemicals that have stimulant drug effects and that supposedly boost energy. Ginseng abuse syndrome is a group of symptoms associated with the overuse of ginseng, including high blood pressure, insomnia, nervousness, confusion, and depression.

glucagon a hormone from the pancreas that stimulates the liver to release glucose into the blood when blood glucose concentration dips.

glucose (GLOO-cose) a single sugar used in both plant and animal tissues for quick energy; sometimes known as blood sugar and dextrose.

glucose tolerance the ability of the body to respond to dietary carbohydrate by regulating its blood glucose concentration promptly to a normal level.

glycemic effect (gligh-SEEM-ic) a measure of the extent to which a food raises the blood glucose concentration and elicits an insulin response as compared with pure glucose.

glycerol (GLISS-er-all) an organic compound, three carbons long, of interest here because it serves as the backbone for triglycerides

glycine a nonessential amino acid, promoted as an ergogenic aid because it is a precursor of the high-energy compound phosphocreatine. Other amino acids that are commonly pack aged for athletes but are equally useless include ornithine, arginine, Iysine, and the branched-chain amino acids.

glycogen (GLY-co-gen) a polysaccharide composed of glucose, made and stored by liver and muscle tissues of human beings and animals as a storage form of glucose. Glycogen is not a significant food source of carbohydrate and is not counted as one of the complex carbohydrates in foods.

goiter (GOY-ter) enlargement of the thyroid gland due to iodine deficiency is simple goiter; goiter due to an excess is toxic goiter.

good source on a food label, 10 to 19% of the Daily Value per serving.

good source of fiber on a food label, 2.5 g to 4.9 g fiber per serving.

gout a painful form of arthritis resulting from a metabolic abnormality in which excessive amounts of the waste product uric acid collect in the blood and uric acid salt is deposited as crystals in the joints.

grams units of weight. A gram (g) is the weight of a cubic centimeter (cc) or milliliter (ml) of water under defined conditions of temperature and pressure. About 28 grams equal an ounce.

granulated sugar common table sugar, crystalline sucrose, 99.9% pure.

granules small grains. Starch granules are packages of starch molecules. Various plant species make starch granules of varying shapes.

GRAS list (where GRAS stands for Generally Recognized As Safe) a list established by the FDA, of food additives long in use and believed safe.

green pills, fruit pills, pills containing dehydrated, crushed vegetable or fruit matter. An advertisement may claim that each pill equals a pound of fresh produce, but in reality a pill may equal one small forkful—minus nutrient losses incurred in processing.

ground water water that comes from underground aquifers.

growth hormone a hormone produced by the brain's pituitary gland that regulates normal growth and development. Also called somatotropin.

growth hormone releasers herbs or pills that supposedly regulate hormones; falsely promoted for enhancing athletic performance.

guarana a reddish berry found in Brazil's Amazon valley that is contains seven times as much caffeine as its relative the coffee bean. It is used as an ingredient in carbonated sodas and taken in powder or tablet form to enhance speed and endurance and serve as an aphrodisiac, a "cardiac tonic," an "intestinal disinfectant," and a smart drug that supposedly improves memory and concentration and wards off senility. High doses may stress the heart and can cause panic attacks.

hard water water with high calcium and magnesium concentrations.

Hazard Analysis Critical Control Point (HACCP) a systematic plan to identify and correct potential microbial hazards in the manufacturing, distribution, and commercial use of food products.

hazard a state of danger; used to refer to any circumstance in which harm is possible under normal conditions of use.

HDL (high-density lipoproteins) lipoproteins, containing a large proportion of protein, that return cholesterol from storage places to the liver for dismantling and disposal.

healthy on a food label, low in fat, saturated fat, cholesterol, and sodium and containing at least 10% of the Daily Value for vitamin A, vitamin C, iron, calcium, protein, or fiber.

heart attack the event in which the vessels that feed the heart muscle become closed off by an embolism, thrombus, or other cause with resulting sudden tissue death. A heart attack is also called a myocardial infarction (myo means "muscle"; cordial means "of the heart"; infarct means "tissue death").

heartburn a burning sensation in the chest (in the area of the heart) area caused by backflow of stomach acid into the esophagus.

heat exhaustion a fluid-depleted state with slightly elevated body temperature (below 104° Fahrenheit) that, while usually not dangerous, requires intake of fluid and rest in a cool place to avoid heat stroke.

heat stroke an acute and life-threatening reaction to heat buildup in the body.

heavy metal any of a number of mineral ions such as mercury and lead; so called because they are of relatively high atomic weight. Many heavy metals are poisonous.

heme (HEEM) the iron-containing portion of the hemoglobin and myoglobin molecules.

hemlock any part of the hemlock plant, which causes severe pain, convulsions, and death within 15 minutes.

hemoglobin (HEEM-oh-globe-in) the oxygen-carrying protein of the blood; found in the red blood cells (hemo means "blood"; globin means spherical protein").

hemorrhoids (HEM-or-oids) swollen, hardened (varicose)veins in the rectum, usually caused by the pressure resulting from constipation.

hernia a protrusion of an organ or part of an organ through the wall of the body chamber that normally contains the organ. An example is a hiatal (high-AY-tal) hernia, in which part of the stomach protrudes up through the diaphragm into the chest cavity, which contains the esophagus, heart, and lungs.

hiccups spasms of both the vocal cords and the diaphragm, causing periodic, audible, short, inhaled coughs. Can be caused by irritation of the diaphragm, indigestion, or other causes. Hiccups usually resolve in a few minutes, but can have serious effects if prolonged. Breathing in to a paper bag (inhaling carbon dioxide) or dissolving a teaspoon of sugar in the mouth may stop them.

high as used on a food label, 20% or more of the Daily Value for a given nutrient per serving; synonyms include "rich in" or "excellent source."

high fiber on a food label, 5 g or more per serving. (Foods making high-fiber claims must fit the definition of low fat, or the level of total fat must appear next to the high-fiber claim.)

high-temperature-short-time (HTST) principle the rule that every 10°C (18°F) rise in processing temperature brings about an approximately tenfold increase in microbial destruction, while only doubling nutrient losses.

histamine a substance that participates in causing inflammation; produced by cells of the immune system as part of a local immune reaction to an antigen.

homogenized milk milk treated to mix the fat evenly with the watery part (fat ordinarily floats to the top as cream). Heated milk is forced under high pressure through small openings to emulsify the fat.

honey a concentrated solution primarily composed of glucose and fructose produced by enzymatic digestion of the sucrose in nectar by bees.

hormones chemicals that are secreted by glands into the blood in response to conditions in the body that require regulation. These chemicals serve as messengers, acting on other organs to maintain constant conditions.

human somatotropin (MST) human growth hormone.

hunger the physiological craving for food; the progressive discomfort, illness, and pain resulting from the lack of food. The word hunger may also refer to the condition of individuals or populations lacking basic foods needed to provide the energy and nutrients that support health.

husk the outer, inedible part of a grain.

hydrogenation (high-droh-gen-AY-shun) the process of adding hydrogen to unsaturated fatty acids to make fat more solid and resistant to the chemical change of oxidation.

hydroxyapatite (hi-DROX-ee-APP-uh-tight) the chief crystal of bone, formed from calcium and phosphorus.

hyperactivity (in children) a syndrome characterized by inattention, impulsiveness, and excess motor activity. Usually occurs before age seven, lasts six months or more, and does not entail mental illness or mental retardation. Also called attention deficit disorder or hyperkinesis and may be associated with minimal brain damage.

hyperglycemia (HIGH-per-gligh-SEEM-ee-uh) an abnormally high blood glucose concentration (hyper means "too much"; glyce means "glucose"; emia means "in the blood").

hypersensitivity see allergy.

hypertension high blood pressure.

hypertrophy (high-PURR-tro-fee) an increase in size (for example, of a muscle) in response to use.

hypoglycemia a blood glucose concentration below normal, a symptom that may indicate any of several diseases, including impending diabetes (NIDDM).

hypothalamus (high-poh-THAL-uh-mus) a part of the brain that senses a variety of conditions in the blood, such as temperature, glucose content, salt content, and others. It signals other parts of the brain or body to adjust those conditions when necessary.

hypothermia a below-normal body temperature.

immunity specific disease resistance, derived from the immune system's memory of prior exposure to specific disease agents and its ability to mount a swift defense against them.

implantation the stage of development, during the first two weeks after conception, in which the fertilized egg embeds itself in the wall of the uterus and begins to develop.

incidental additives substances that can get into food not through intentional introduction but as a result of contact with the food during growing, processing, packaging, storing, or some other stage before the food is consumed. The terms accidental and indirect additives mean the same thing.

incomplete proteins proteins lacking, or low in, one or more of the essential amino acids.

infectious diseases diseases caused by bacteria, viruses, parasites, and other microbes, which can be transmitted from one person to another through air, water or food, by contact, or through vector organisms such as mosquitoes or fleas.

initiation an event, probably in the cell's genetic material, caused by radiation or by a chemical carcinogen that can give rise to cancer.

inosine an organic chemical that is falsely said to "activate cells, produce energy, and facilitate exercise." Studies have shown that it actually reduces the endurance of runners.

inositol (in-OSS-ih-tall) a nonessential nutrient found in cell membranes.

insoluble fibers the tough, fibrous structures of fruits, vegetables, and grains; indigestible food components that do not dissolve in water.

insulin a hormone secreted by the pancreas in response to a high blood glucose concentration. It assists cells in drawing glucose from the blood.

integrated pest management (IPM) management of pests using a combination of natural and biological controls and minimal or no application of pesticides.

intervention studies studies of populations in which observation is accompanied by experimental manipulation of some population members—for example, a study in which half of the subjects (the experimental subjects) follow diet advice to reduce fat intakes while the other half (the control subjects) do not, and both groups' heart health is monitored.

intestine the body's long, tubular organ of digestion and the site of nutrient absorption.

intrinsic factor a factor found inside a system. The intrinsic factor necessary to prevent pernicious anemia is now known to be a compound that helps in the absorption of vitamin B12.

invert sugar a mixture of glucose and fructose formed by the splitting of sucrose in an industrial process. Sold only in liquid form and sweeter than sucrose, invert sugar forms during certain cooking procedures and works to prevent crystallization of sucrose in soft candies and sweets.

ions (EYE-ons) electrically charged particles, such as sodium (positively charged) or chloride (negatively charged).

iron deficiency the condition of having depleted iron stores, which, at the extreme, causes iron-deficiency anemia.

iron overload the state of having more iron in the body than it needs or can handle. Too much iron is toxic and can damage the liver.

iron-deficiency anemia a form of anemia caused by iron deficiency and characterized by red blood cell shrinkage and colorloss. Accompanying symptoms are weakness, apathy, headaches, pallor, intolerance to cold, and inability to pay attention.

irradiation application of ionizing radiation to foods to reduce insect infestation or microbial contamination, or slow the ripening or sprouting process.

irritable bowel syndrome intermittent disturbance of bowel function, especially diarrhea or alternating diarrhea and constipation, associated with diet, lack of physical activity, or psychological stress.

IU (international unit) a measure of fat-soluble vitamin activity.

kefir a yogurt-based beverage.

kelp tablets tablets made from dehydrated kelp, a kind of seaweed used by the Japanese as a foodstuff.

keratin (KERR-uh-tin) the normal protein of hair and nails.

keratinization accumulation of keratin in a tissue; a sign of vitamin A deficiency.

ketone bodies (KEE-tone) acidic, fat-related compounds that can arise from the incomplete breakdown of fat and help to feed the brain when carbohydrate is not available.

ketosis (kee-TOE-sis) an undesirably high concentration of ketone bodies, such as acetone, in the blood or urine.

kidneys a pair of organs that filter wastes from the blood, make urine, and release it to the bladder for excretion from the body.

kilocalories, kcalories see calories.

kombucha a fermented tea drink of questionable safety; purported to bestow health benefits on the drinker. Not made from mushrooms, but often called mushroom tea.

kudzu a weedy vine, whose roots are harvested and used by Chinese herbalists as a treatment for alcoholism. Kudzu reportedly reduces alcohol absorption by up to 50 percent in rats.

kwashiorkor (kwash-ee-OR-core, kwashee-or-CORE) a disease related to protein malnutrition, with a set of recognizable symptoms, such as edema.

laboratory studies studies that are performed under tightly controlled conditions and are designed to pinpoint causes and effects. Such studies often use animals as subjects.

Iactalbumin see casein.

lactase the intestinal enzyme that splits the disaccharide lactose to monosaccharides during digestion.

lactation production and secretion of breast milk for the purpose of nourishing an infant.

lactic acid a product of the incomplete breakdown of glucose during anaerobic metabolism. When oxygen becomes available, lactic acid can be completely broken down for energy or converted back to glucose.

Iacto-ovo vegetarian includes dairy products, eggs, vegetables, grains, legumes, fruits, and nuts; excludes meats and seafood.

Iacto-vegetarian includes dairy products, vegetables, grains, legumes, fruits, and nuts; excludes meats, seafood, and eggs.

Iactoferrin (lack-toe-FERR-in) a factor in breast milk that binds iron and keeps it from supporting the growth of the infant's intestinal bacteria.

Iactose a disaccharide composed of glucose and galactose; sometimes known as milk sugar (lact means "milk"; ose means "sugar").

Iactose intolerance inability to digest lactose due to a lack of the enzyme lactase. Iactose, maltose, sucrose the disaccharides.

lapse a falling back into a former condition. In weight maintenance, a temporary backslide into old habits.

large intestine the portion of the intestine that completes the absorption process.

LDL (low-density lipoproteins) lipoproteins, containing a large proportion of cholesterol, that transport lipids from the liver to other tissues such as muscle and fat.

lean on a food label, less than 10 g of fat, less than 4 g of saturated fat, and less than 95 mg cholesterol per serving.

learning disability an altered ability to learn basic cognitive skills such as reading, writing, and mathematics.

leavened (LEV-end): literally, "lightened" by yeast cells, which digest some carbohydrate components of the dough and leave behind bubbles of gas which make the bread rise.

lecithin (LESS-ih-thin) a phospholipid manufactured by the liver and also found in many foods; a major constituent of cell membranes.

legumes (leg-GOOMS, LEG-yooms) plants of the bean and pea family having roots with nodules that contain special bacteria. These bacteria can trap nitrogen from the air in the soil and make it into compounds that become part of the seed. The seeds are rich in high-quality protein compared with those of most other plant foods.

Ieptin an appetite-suppressing hormone produced in the fat cells that conveys information about body fatness to the brain; believed to be involved in the maintenance of body composition (leptos means "slender").

less, fewer, reduced on a food label, containing at least 25% less of a nutrient or calories than a reference food. This may occur naturally or as a result of altering the food. For example, pretzels, which are usually low in fat, can claim to provide less fat than potato chips, a comparable food.

Ievulose an older name for fructose.

license to practice permission under state or federal law, granted on meeting specified criteria, to use a certain title (such as dietitian) and to offer certain services. Licensed dietitians may use the initials LD after their names.

Life expectancy the average number of years lived by people in a given society.

life span the maximum number of years of life attainable by a member of a species.

light this descriptor has three meanings on labels: a serving provides one-third fewer calories or half the fat of the regular M product; a serving of a low-calorie, low-fat food provides half the sodium normally present; and the product is light in color and texture, so long as the label makes this intent clear, as in "light brown sugar."

limbic system a group of tissues at the center of the brain responsible for feelings of pleasure and involved in the addiction process.

limiting amino acid a term given to an essential amino acid present in dietary protein in an insufficient amount, so that it limits the body's ability to build protein.

Iinoleic acid (lin-oh-LAY-ic) and linolenic acid (lin-oh-LEN-ic) polyunsaturated fatty acids that are essential nutrients for human beings.

lipid (LIP-id) a family of compounds soluble in organic solvents but not in water. Lipids include triglycerides (fats and oils), phospholipids, and sterols.

Iipoic acid (lip-OH-ic) a nonessential nutrient.

lipoproteins (LIP-oh-PRO-teens) clusters of lipids associated with protein, which serve as transport vehicles for lipids in blood and lymph. Major lipoprotein classes are the chylomicrons, the LDL, and the HDL.

liver a large, lobed organ that lies just under the ribs. It filters the blood, removes and processes nutrients, manufactures materials for export to other parts of the body, and destroys toxins or stores them to keep them out of the circulation.

longevity long duration of life.

Iow birthweight a birthweight of less than 5 1/2 pounds (2,500 grams); used as a predictor of probable health problems in the newborn and as a probable indicator of poor nutrition status of the mother before and/or during pregnancy. Low-birth weight infants are of two different types. Some are premature; they are born early and are the right size for their gestational age. Others have suffered growth failure in the uterus; they may or may not be born early, but they are small for gestational age (small for date).

Iow calorie as used on a food label, 40 calories or less per serving.

Iow cholesterol on a food label, 20 mg or less of cholesterol and 2 g or less saturated fat per serving.

Iow fat 3 g or less fat per serving.

Iow saturated fat 1 g or less saturated fat per serving.

Iow sodium on a food label, 140 mg or less sodium per serving.

LPL (lipoprotein lipase) an enzyme mounted on the surfaces of fat cells that splits triglycerides in the blood into fatty acids and glycerol to be absorbed into the cells for reassembly and storage.

lungs the body's organs of gas exchange. Blood circulating through the lungs releases its carbon dioxide and picks up fresh oxygen to carry to the tissues.

lymph (LIMF) the fluid that moves from the bloodstream into tissue spaces and then travels in its own vessels, which eventually drain back into the bloodstream.

Ma huang an evergreen plant derivative that supposedly boosts energy and helps with weight control but that contains ephedrine, a cardiac stimulant that is dangerous in combination with kola nut or other caffeine-containing substances.

macrobiotic diet a vegan diet that progressively eliminates more and more foods. Ultimately, only brown rice and small amounts of water or herbal tea are consumed; taken to extremes, macrobiotic diets have resulted in malnutrition and even death.

macular degeneration a common, progressive loss of function of that part of the retina that is most crucial to focused vision. This degeneration leads to blindness.

mad cow disease formally, bovine spongiform encephalopathy (BSE); a fatal viral disease of cattle affecting the brain and nervous system. Valid scientific evidence suggests that BSE poses no threat to human beings.

major minerals essential mineral nutrients found in the human body in amounts larger than 5 grams.

malnutrition any condition caused by excess or deficient food energy or nutrient intake or by an imbalance of nutrients. Nutrient or energy deficiencies are classed as forms of under nutrition; nutrient or energy excesses are classed as forms of overnutrition.

maltitol, mannitol, sorbitol, xylitol sugar alcohols that can be derived from fruits or commercially produced from dextrose; absorbed more slowly and metabolized differently than other sugars in the human body and not readily used by ordinary mouth bacteria.

maltose a disaccharide composed of two glucose units; some times known as malt sugar.

maple sugar a concentrated solution of sucrose derived from the sap of the sugar maple tree, mostly sucrose. This sugar was once common but is now usually replaced by sucrose and artificial maple flavoring.

marasmus (ma-RAZ-mus) the calorie-deficiency disease; starvation.

margin of safety in reference to food additives, a zone between the concentration normally used and that at which a hazard exists. For common table salt, for example, the margin of safety is 1/5 (five times the concentration normally used would be hazardous).

marginal deficiency see subclinical deficiency.

medical nutrition therapy nutrition services used in the treatment of injury, illness, or other conditions; includes assessment of nutrition status and dietary intake, and corrective applications of diet, counseling, and other nutrition services.

medicinal herbs nonwoody plants, plant parts, or extracts valued by some people for their medicinal qualities, both proved and unproved.

melatonin a hormone of the pineal gland believed to help regulate the body's daily rhythms to reverse the effects of jet lag, and to promote sleep. Claims for life extension or enhancement of sexual prowess are without merit. Proof of melatonin's safety or effectiveness is lacking.

MEOS (microsomal ethanol oxidizing system) a system of enzymes in the liver that oxidize not only alcohol but also several classes of drugs.

methanol an alcohol produced in the body continually by all cells.

MFP factor a factor (identity unknown) present in meat, fish, and poultry that enhances the absorption of nonheme iron present in the same foods or in other foods eaten at the same time.

microvilli (MY-croh-VILL-ee, MY-croh-VILL-eye) tiny, hairlike projections on each cell of every villus that can trap nutrient particles and transport them into the cells (singular: microvillus).

milk anemia iron-deficiency anemia caused by drinking so much milk that iron-rich foods are displaced from the diet.

mineral water water from a spring or well that typically contains 250 to 500 parts per million (ppm) of minerals. Minerals give water a distinctive flavor. Many mineral waters are high in sodium.

minerals naturally occurring, inorganic, homogeneous substances; chemical elements.

moderation the dietary characteristic of providing constituents within set limits, not to excess.

modified atmosphere packaging (MAP) preservation of a perishable food by packaging it in a gas-impermeable container from which air has been removed, or to which another gas mixture has been added.

molasses a syrup left over from the refining of sucrose from sugar cane; a thick, brown syrup. The major nutrient in molasses is iron, a contaminant from the machinery used in processing it.

monoglycerides (mon-oh-GLISS-er-ides) a product of the digestion of lipids; glycerol molecules with one fatty acid attached (mono means "one"; glyceride means "a compound of glycerol").

monosaccharides single sugar units (mono means "one"; saccharide means "sugar unit").

monounsaturated fats triglycerides in which one or more of the fatty acids has one point of unsaturation (is monounsaturated).

monounsaturated fatty acid a fatty acid containing one point of unsaturation.

more or added fiber on a food label, at least 2.5 g more per serving than a reference food.

more, extra as used on a food label, contains at least 10% more of the Daily Value than in a reference food. The nutrient may be added or may occur naturally.

MSG symptom complex the acute, temporary, and self-limiting reactions experienced by many people upon ingesting a large dose of MSG. The name MSG symptom complex, given by FDA, replaces the former Chinese restaurant syndrome.

mucus (MYOO-cus) a slippery coating of the digestive tract lining (and other body linings) that protects the cells from exposure to digestive juices (and other destructive agents). The adjective form is mucous (same pronunciation). The digestive tract lining is a mucous membrane.

muscle endurance the ability of a muscle to contract repeatedly within a given time without becoming exhausted.

mutual supplementation the strategy of combining two incomplete protein sources so that the amino acids in each food make up for those lacking in the other food. Such protein combinations are sometimes called complementary proteins.

myoglobin (MYE-oh-globe-in) the oxygen-holding protein of the muscles (myo means "muscle").

naloxone a drug used in the treatment of narcotic addictions.

natural foods a term that has no legal definition.

natural water water obtained from a spring or well that is certified to be safe and sanitary. The mineral content may not be changed, but the water may be treated in other ways such as by filtration or ozonization.

naturally occurring sugars sugars present in a food naturally, and not added.

nephrons the working units in the kidneys, consisting of intermeshed blood vessels and tubules.

neural tube defects a group of nervous system abnormalities caused by interruption of the normal early development of the neural tube.

neural tube the embryonic tissue that later forms the brain and spinal cord.

neurotoxins poisons that act upon the cells of the nervous system.

neurotransmitter a substance released from the end of a nerve cell in response to a nerve impulse. The neurotransmitter diffuses across the gap to the next nerve cell, and alters that cell's membrane to make the cell more or less likely to fire.

niacin a B vitamin needed in energy metabolism. Niacin can be eaten preformed or can be made in the body from tryptophan, one of the amino acids. Other forms of niacin are nicotinic acid, niacinamide, and nicotinamide.

niacin equivalents the amount of niacin present in food, including the niacin that can theoretically be made from its precursor tryptophan, present in the food.

night blindness slow recovery of vision after exposure to flashes of bright light at night; an early symptom of vitamin A deficiency.

nitrogen balance the amount of nitrogen consumed compared with the amount excreted in a given time period.

nonnutrients a term used in this book to mean compounds other than the six nutrients that are present in foods.

nonpoint pollution water pollution caused by runoff from all over an area, rather than from discrete "point" sources. An example is the pollution in runoff from farm fields.

norepinephrine a compound related to epinephrine that helps to elicit the stress response.

nori a type of seaweed popular in Asian, particularly Japanese, cooking.

nutrient additives vitamins and minerals added to improve nutritive value.

nutrient density a measure of nutrients provided per calorie of food.

nutrients components of food that are indispensable to the body's functioning. They provide energy, serve as building material, help maintain or repair body parts, and support growth. The nutrients include water, carbohydrate, fat, protein, vitamins, and minerals.

nutrition the study of the nutrients in foods and in the body; sometimes also the study of human behaviors related to food.

nutritional yeast a preparation of yeast cells, often praised for its high nutrient content. Yeast is a source of B vitamins, as are many other foods. Also called brewer's yeast; not the yeast used in baking.

nutritionist someone who engages in the study of nutrition. Some nutritionists are RDs, whereas others are self-described experts whose training is questionable and who are not qualified to give advice. In states with responsible legislation, the term applies only to people who have masters of science (MS) or doctor of philosophy (PhD) degrees from properly accredited institutions.

obesity overfatness with adverse health effects, as determined by reliable measures and interpreted with good medical judgment. Obesity is sometimes defined as a body mass index over 30.

octacosanol an alcohol extracted from wheat germ, often falsely promoted as enhancing athletic performance.

oils lipids that are liquid at room temperature (70°F or 25°C).

Olestra a noncaloric artificial fat made from sucrose and fatty acids; olestra's chemical name is sucrose polyester.

omega-3 fatty acid a polyunsaturated fatty acid with its end most double bond three carbons from the end of its carbon chain; relatively newly recognized as important in nutrition. Linolenic acid is an example.

omega-6 fatty acid a polyunsaturated fatty acid with its end most double bond six carbons from the end of the carbon chain; long recognized as important in nutrition. Linoleic acid is an example.

omnivores people who eat foods of both plant and animal origin, including animal flesh.

oral rehydration therapy (ORT) oral fluid replacement for children with severe diarrhea caused by infectious disease. ORT enables a mother to mix a simple solution for her child from substances that she has at home.

organic carbon containing. Four of the six classes of nutrients are organic: carbohydrate, fat, protein, and vitamins. Strictly speaking, organic compounds include only those made by living things and do not include carbon dioxide and a few carbon salts.

organic foods understood to mean foods grown without synthetic pesticides or fertilizers; in chemistry, however, all foods are made mostly of organic (carbon-containing) compounds.

organic halogen an organic compound containing one or more atoms of a halogen—fluorine, chlorine, iodine, or bromine.

organs discrete structural units made of tissues that perform specific jobs, such as the heart, liver, and brain.

osteomalacia (OS-tee-o-mal-AY-shuh) the vitamin D-deficiency disease in adults (osteo means "bone"; mal means "bad"). Symptoms include bending of the spine and bowing of the legs.

osteoporosis (OSS-tee-oh-pore-OH-sis) a condition of older persons in which the bones become porous and fragile (osteomeans "bones"; poros means "porous"); also known as adult bone loss. Type I osteoporosis is characterized by rapid loss of primarily trabeculer bone; Type II is characterized by steady gradual losses of both trabecular and cortical bone.

outcrossing the unintended breeding of a domestic crop with a related wild species.

overload an extra physical demand placed on the body; an increase in the frequency, duration, or intensity of an activity. A principle of training is that for a body system to improve, it must be worked at frequencies, durations, or intensities that increase by increments.

ovo-vegetarian includes eggs, vegetables, grains, legumes, fruits, and nuts; excludes meats, seafood, and milk products.

ovum the egg, produced by the mother, that unites with a sperm from the father to produce a new individual.

oxidant a compound (such as oxygen itself) that oxidizes other compounds. Compounds that prevent oxidation are called antioxidants, whereas those that promote it are called prooxidants.

oxidation interaction of a compound with oxygen; in this case, a damaging effect by reactive oxygen.

oxidative stress damage inflicted on living systems by free radicals.

oyster shell a product made from the powdered shells of oysters; sold as a calcium supplement, but not well absorbed by the digestive system.

pancreas an organ with two main functions. One is an endocrine function—the making of hormones such as insulin, which it releases directly into the blood (endo means "into" the blood). The other is an exocrine function—the making of digestive enzymes, which it releases through a duct into the small intestine to assist in digestion (exo means "out" into a body cavity or onto the skin surface).

pancreatic juice fluid secreted by the pancreas that contains enzymes to digest carbohydrate, fat, and protein as well as sodium bicarbonate, a neutralizing agent.

pantothenic acid (PAN-to-THEN-ic) a B vitamin.

partial vegetarian includes seafood, poultry, eggs, dairy products, vegetables, grains, legumes, fruits, and nuts; excludes or strictly limits red meats.

partitioned foods foods composed of parts of whole foods, such as butter (from milk), sugar (from beets or cane), or corn oil (from corn). Partitioned foods are usually empty of nutrients and are not nutritious.

pasteurization the treatment of milk with heat sufficient to kill certain pathogens (disease-causing microbes) commonly transmitted through milk; not a sterilization process. Pasteurized milk retains bacteria that cause milk spoilage. Raw milk, even if labeled "certified," transmits many food-borne diseases to people each year and should be avoided.

pasteurized milk milk that is treated by pasteurization.

peak bone mass the highest attainable bone density for an individual; developed during the first three decades of life.

pellagra (pell-AY-gra) the niacin-deficiency disease (pellis means "skin"; ogra means "rough"). Symptoms include the "4 Ds": diarrhea, dermatitis, dementia, and, ultimately, death.

peptide bond a bond that connects one amino acid with another, forming a link in a protein chain.

percent fat free may be used on a food label, only if the product meets the definition of low fat or fat free. Requires disclosure of g fat per 100 g food.

peristalsis (perri-STALL-sis) the wavelike muscular squeezing of the esophagus, stomach, and small intestine that pushes their contents along.

pernicious anemia (per-NISH-us) a vitamin Bl2-deficiency disease, caused by lack of intrinsic factor and characterized by large, immature red blood cells and damage to the nervous system (pernicious means "highly injurious or destructive").

persistent of a stubborn or enduring nature; with respect to food contaminants, the quality of remaining unaltered and unexcreted in plant foods or in the bodies of animals and human beings.

pesco-vegetarian same as partial vegetarian, but eliminates poultry.

pesticides chemicals used to control insects, diseases, weeds, fungi, and other pests on crops and around animals. Used broadly, the term includes herbicides (to kill weeds), insecticides (to kill insects), and fungicides (to kill fungi).

pH a measure of acidity on a point scale. A solution with a pH of 1 is a strong acid; a solution with a pH of 7 is neutral; a solution with a pH of 14 is a strong base.

phenylpropanolamine (PPA) a stimulant of the sympathetic nervous system used as a weight-loss agent and available in over-the-counter medications.

phosphate salt a salt that has been demonstrated to raise the concentration of a metabolically important compound (diphosphoglycerate) in red blood cells and enhance the cells' potential to deliver oxygen to muscle cells. The salts may cause calcium losses from the bones if taken in excess.

phospholipids (FOSS-foh-LIP-ids) one of the three main classes of dietary lipids. These lipids are similar to triglycerides, but each has a phosphorus-containing acid in place of one of the fatty acids. Phospholipids are present in all cell membranes.

photosynthesis the synthesis of carbobydrates by green plants from carbon dioxide and water using the green pigment chlorophyll to capture the sun's energy (photo means "light"; synthesis means "making").

phytates compounds present in plant foods (particularly whole grains) that bind iron and prevent its absorption.

phytochemicals nonnutrient compounds in plant-derived foods having biological activity in the body.

pica (PIE-ka) a craving for nonfood substances. Also known as geophagia (gee-oh-FAY-gee-uh) when referring to clay eating, and pagophagia (pag-oh-FAY-gee-uh) when referring to ice craving (geo means "earth"; pago means "frost"; phagia means "to eat").

placebo a sham treatment often used in scientific studies; an inert harmless medication. The placebo effect is the healing effect that the act of treatment, rather than the treatment itself, often has.

placenta (pla-SEN-tuh) the organ that develops inside the uterus in early pregnancy in which the mother's and fetus's circulatory systems intertwine and in which exchange of materials between maternal and fetal blood takes place. The fetus receives nutrients and oxygen across the placenta; the mother's blood picks up carbon dioxide and other waste materials to be excreted via her lungs and kidneys.

plant sterols lipid extracts of plants, called ferulic acid, oryzanol, phytosterols, or "adaptogens," marketed with false claims that they contain hormones or enhance hormonal activity.

plant-pesticides substances produced within plant tissues that kill or repel attacking organisms.

plaque (PLACK) in reference to the teeth, a mass of microorganisms and their deposits on the crowns and roots of the teeth, a forerunner of dental caries and gum disease. (The term plaque is used in another connection—arterial plaque in atherosclerosis. See Chapter 11.)

plaques (PLACKS) in reference to heart disease, mounds of lipid material, mixed with smooth muscle cells and calcium, that develop in the artery walls in atherosclerosis (blacken means "patch").

platelets tiny cell-like fragments in the blood, important in blood clot formation (platelet means "little plate").

point of unsaturation a site in a molecule where the bonding is such that additional hydrogen atoms can easily be attached.

polypeptides protein fragments of many (more than ten) amino acids bonded together. (A chain of between four and ten is called an oligopeptide.)

polysaccharides another term for complex carbohydrates, compounds of long strands of glucose units linked together (poly means "many").

polyunsaturated fats triglycerides in which one or more of the fatty acids has two or more points of unsaturation (is polyunsaturated).

polyunsaturated fatty acid (PUFA) a fatty acid with two or more points of unsaturation.

postprandial hypoglycemia a drop in blood glucose that follows a meal and is accompanied by symptoms of the stress response. Also called reactive hypoglycemia.

powdered milk dehydrated milk solids. Some powdered milks rehydrate easily (instant milk); others require extensive blending. Both whole and nonfat milk can be powdered.

precursor control control of a compound's synthesis by the availability of that compound's precursor. The more precursor there is, the more of the compound is made.

precursors, provitamins compounds that can be converted into active vitamins.

preeclampsia a potentially dangerous condition during pregnancy characterized by edema, hypertension, and protein in the urine.

pregame meal a meal eaten three to four hours before athletic competition.

pregnancy-induced hypertension (PIH) a form of high blood pressure that can develop in later pregnancy.

premature infant see low birthweight.

premenstrual syndrome (PMS) a cluster of symptoms that some women experience prior to and during menstruation. They include, among others, abdominal cramps, back pain, swelling, headache, painful breasts, and mood changes.

preservatives antimicrobial agents, antioxidants, chelating agents, radiation, and other additives that retard spoilage or preserve desired qualities, such as softness in baked goods.

processed foods foods subjected to any process, such as milling, alteration of texture, addition of additives, cooking, or others. Depending on the starting material and the process, a processed food may or may not be nutritious.

promoters factors that do not initiate cancer but speed up its development once initiation has taken place.

proportionality see balance.

proof a statement of the percentage of alcohol in an alcoholic beverage. Liquor that is 100 proof is 50% alcohol; 90 proof is 45%; and so forth.

prostaglandins hormonelike compounds (eicosanoids) related to and derived from polyunsaturated fatty acids (prostagland because the first such compound discovered was from the prostate gland).

protease inhibitors compounds that inhibit the action of protein-digesting enzymes.

protein digestibility - corrected amino acid score (PDCAAS) a measuring tool used to determine protein quality. PDCAAS reflects a protein's digestibility as well as the proportions of amino acids that it provides.

protein efficiency ratio (PER) a measure of protein quality assessed by determining how well a given protein supports weight gain in growing rats. The PER is used to judge the quality of protein in infant formulas and baby foods.

protein-energy malnutrition (PEM) also called protein-calorie malnutrition (PCM) the world's most widespread malnutrition problem, including both marasmus and kwashiorkor and states in which they overlap.

protein-sparing action the action of carbohydrate and fat in providing energy that allows protein to be used for purposes it alone can serve.

proteins compounds composed of carbon, hydrogen, oxygen, and nitrogen and arranged as strands of amino acids. Some amino acids also contain the element sulfur.

puberty the period in life when a person develops sexual maturity and the ability to reproduce.

public health nutritionist a dietitian who specializes in public health nutrition.

public water water from a municipal or county water system that has been treated and disinfected.

purified water water that has been treated by distillation or other physical or chemical processes that remove dissolved solids. Because purified water contains no minerals or contaminants, it is useful for medical and research purposes.

pyloric valve (pye-LORE-ick) the circular muscle of the lower stomach that regulates the flow of partly digested food into the small intestine. Also called pyloric sphincter.

radiation ionizing rays that act as a preservative by disrupting chemical structures within cells, including the cell bodies of microorganisms. Irradiation is a process, but it causes new substances to form in the food; therefore radiation is considered to be an additive.

radiolytic products chemicals formed during irradiation of food.

raw sugar the first crop of crystals harvested during sugar processing. Raw sugar cannot be sold in the United States because it contains too much filth (dirt, insect fragments, and the like). Sugar sold as "raw sugar" domestically is not actually raw but has gone through more than half of the refining steps.

RE (retinal equivalent) a measure of vitamin A activity; the amount of retinal that the body will derive from a food containing vitamin A (preformed retinal) or its precursor carotene.

Recommended Dietary Allowances (RDA) daily consumption levels of energy and selected nutrients judged by the Food and Nutrition Board to meet the known nutrient needs of practically all healthy people.

reduced calorie on a food label, at least 25% lower in calories than a "regular," or reference, food.

reduced or less cholesterol on a food label, at least 25% less cholesterol than a reference food and 2 g or less saturated fat per serving.

reduced saturated fat on a food label, 25% or less of saturated fat and reduced by more than 1 gram saturated fat per serving compared with a reference food.

reference woman and man actual median figures for heights and weights of people of each age-sex group in the U.S. population.

refined refers to the process by which the coarse parts of food products are removed. For example, the refining of wheat into white flour involves removing three of the four parts of the kernel—the chaff, the bran, and the germ—leaving only the endosperm, composed mainly of starch and a little protein.

registered dietitian (RD) a dietitian who has graduated from a university or college after completing a program of dietetics. The program must be approved or accredited by the American Dietetic Association (or Dietitians of Canada). The dietitian must serve in an approved internship, coordinated program, or preprofessional practice program to practice the necessary skills; pass the five parts of the association's registration examination; and maintain competency through continuing education. Many states also require licensing for practicing dietitians.

registration listing with a professional organization that requires specific course work, experience, and passing of an examination.

relapse the outcome of an uncontrolled series of lapses, such as regaining of weight after successful loss and returning to old patterns of eating.

requirement the amount of a nutrient that will just prevent the development of specific deficiency signs; distinguished from the RDA, which is a generous allowance with a margin of safety.

residues whatever remains. In the case of pesticides, those amounts that remain on or in foods when people buy and use them.

retina (RET-in-uh) the layer of light-sensitive nerve cells lining the back of the inside of the eye.

retinal one of the active forms of vitamin A made from beta carotene in animal and human bodies; an antioxidant nutrient. Other active forms are retinal and retinoic acid.

rhodopsin the light-sensitive pigment of the cells in the retina; it contains vitamin A (rhod refers to the rod-shaped cells; opsin means "visual protein").

riboflavin (RIBE-o-flay-vin) a B vitamin active in the body's energy-releasing mechanisms.

rickets the vitamin D-deficiency disease in children; characterized by abnormal growth of bone and manifested in bowed legs or knock-knees, outward-bowed chest, and knobs on the ribs.

risk factors factors known to be related to (or correlated with) diseases but not proven to be causal.

roughage (RUFF-idge) the rough parts of food; an imprecise term that has largely been replaced by the term fiber.

royal jelly a substance produced by worker bees and fed to the queen bee; often falsely promoted as enhancing athletic performance.

saccharin a zero-calorie sweetener used freely in the United States but restricted in Canada.

safety the practical certainty that injury will not result from the use of a substance.

salts compounds composed of charged particles (ions). An example is potassium chloride (K+CI-).

sassafras root bark from the sassafras tree, once used in beverages but now banned as an ingredient in foods or beverages because it contains cancer-causing chemicals.

satiety (sat-EYE-uh-tee) the feeling of fullness or satisfaction that people feel after meals.

saturated fat free on a food label, less than 0.5 g of saturated fat and less than 0.5 g of trans-fatty acids.

saturated fats triglycerides in which all the fatty acids are saturated.

saturated fatty acid a fatty acid carrying the maximum possible number of hydrogen atoms (having no points of unsaturation). A saturated fat is a triglyceride that contains three saturated fatty acids.

scurvy the vitamin C-deficiency disease.

semivegetarians people who eat only small amounts of meat, or who exclude just certain meats, such as red meats.

serotonin a compound related in structure to (and made from) the amino acid tryptophan. It serves as one of the brain's principal neurotransmitters.

set-point theory the theory that the body tends to maintain a certain weight by means of its own internal controls.

side chain the unique chemical structure attached to the back bone of each amino acid that differentiates one amino acid from another.

simple carbohydrates sugars, including both single sugar units and linked pairs of sugar units. The basic sugar unit is a molecule containing six carbon atoms, together with oxygen and hydrogen atoms.

Simplesse a protein-based fat replacer useful in cold foods or frozen confections.

skinfold test see fatfold test.

small intestine the 20-foot length of small-diameter intestine, below the stomach and abuse the large intestine, that is the major site of digestion of food and absorption of nutrients.

smoking point the temperature at which fat gives off an acrid blue gas.

sodium bicarbonate baking soda, an alkaline salt. In sports, believed to neutralize blood lactic acid and thereby reduce pain and enhance workload. "Soda loading" may cause intestinal bloating and diarrhea.

sodium free on a food label, less than 5 mg per serving soft water water with a high sodium concentration.

soluble fibers indigestible food components that readily dissolve in water and often impart gummy or gel-like characteristics to foods. An example is pectin from fruit used to thicken jellies.

somatotropin see growth hormone.

Special Supplemental Food Program for Women, Infants, and Children (WIC) a USDA program to provide nutrition support to low-income women who are pregnant or who have infants or preschool children. WIC offers coupons redeemable for specific foods to supply the nutrients deemed most needed for growth and development.

sphincter (SFINK-ter) a circular muscle surrounding, and able to close, a body opening.

spina bifida (SPEE-na BIFF-ih-duh) a birth defect: the infant is born with gaps in the bones of the spine, leaving the spinal cord protected only by a sheath of skin in those spots, or with no protection at all. The spinal cord may bulge and protrude through the gaps in the vertebral column.

spirulina a kind of alga ("blue-green manna") that supposedly contains large amounts of protein and vitamin Bl2, suppresses appetite, and improves athletic performance. It does none of these things and is potentially harmful because it is frequently contamined with disease-causing organisms.

spring water water originating from an underground spring or well. It may be bubbly (carbonated) or "flat" or "still," meaning not carbonated. Brand names such as "Spring Pure" do not necessarily mean that the water comes from a spring.

staple foods foods used frequently or daily, for example, rice (in the Far East) or potatoes (in Ireland). If well chosen, these foods are nutritious; certainly, they should be.

starch a plant polysaccharide composed of glucose; highly digestible by human beings.

sterols (STEER-alls) one of the three main classes of dietary lipids. Sterols have a structure similar to that of cholesterol.

stomach a muscular, elastic, pouchlike organ of the digestive tract that grinds and churns swallowed food and mixes it with acid and enzymes, forming chyme.

stone-ground flour flour made by grinding kernels of grain between heavy wheels made of limestone a kind of rock derived from the shells and bones of marine animals. As the stones scrape together, bits of the limestone mix with the flour, enriching it with calcium.

strength the ability of muscles to work against resistance.

stress eating eating in response to stress, an inappropriate activity.

stress fracture a bone injury or break caused by the stress of exercise on the bone surface.

stroke the sudden shutting off of the blood flow to the brain by a thrombus, embolism, or the bursting of a vessel (hemorrhage).

stroke volume the amount of oxygenated blood ejected from the heart toward body hssues at each beat.

subclinical deficiency a nutrient deficiency that has no detectable (clinical) symptoms. The term is often used to scare consumers into buying unneeded nutrient supplements. Also called a marginal deficiency.

subcutaneous fat fat stored directly under the skin (sub means "beneath"; cutaneous refers to the skin).

subsidies government money, derived from taxes, used to support (subsidize) practices that otherwise would force producers to set their prices too high to compete successfully.

sucralose a noncaloric sweetener derived from a chlorinated form of sugar that travels through the digestive tract unabsorbed. Canada has approved the sweetener; in the United States, the FDA is considering its approval.

sucrose (SOO-crose) a disaccharide composed of glucose and fructose; sometimes known as table, beet, or cane sugar.

sucrose polyester any of a family of compounds in which fatty acids are bonded with sugars or sugar alcohols. Olestra is an example.

sugars simple carbohydrates, that is, molecules of either single sugar units or pairs of those sugar units bonded together.

superoxide dismutase (SOD) an enzyme that protects cells from oxidation. When it is taken orally, the body digests and inactivates this protein; it is useless to athletes.

supplements pills, liquids, or powders that contain purified nutrients.

surface water water that comes from lakes, rivers, and reservoirs.

sushi a Japanese dish that consists of vinegar-flavored rice, seafood, and colorful vegetables, typically wrapped in seaweed. Some sushi is wrapped in raw fish; other sushi contains only cooked ingredients.

sustainable able to continue indefinitely. Here the term refers to the use of resources at such a rate that the earth can keep on replacing them, for example, cutting trees no faster than new ones grow and producing pollutants at a rate with which the environment and human cleanup efforts can keep pace. In a sustainable economy, resources do not become depleted, and pollution does not accumulate.

systolic pressure (sis-TOL-ik) the first figure in a blood pressure reading (the "dub" of the heartbeat), which reflects arterial pressure caused by the contraction of the heart's left ventricle.

tannins compounds in tea (especially black tea), and coffee that bind iron. Tannins also denature proteins.

textured vegetable protein processed soybean protein used in products formulated to look and taste like meat, fish, or poultry.

thermic effect of food (TEE) the body's speeded-up metabolism in response to having eaten a meal. Also called diet induced thermogenesis.

thermogenesis the generation and release of body heat associated with the breakdown of body fuels.

thiamin (THIGH-uh-min) a B vitamin involved in the body's use of fuels.

thickening and stabilizing agents ingredients that maintain emulsions, foams, or suspensions or lend a desirable thick consistency to foods. Dextrins (short chains of glucose formed as a breakdown product of starch), starch, and pectin are examples. (Gums such as carrageenan, guar, locust bean, agar, and gum arable are others.)

thrombosis a blood clot (thrombus) that has grown enough to close off a blood vessel. A coronary thrombosis is the closing off of a vessel that feeds the heart muscle. A cerebral thrombosis is the closing off of a vessel that feeds the brain (coronary means "crowning" [the heart]; thrombo means "clot"; the cerebrum is part of the brain).

thrombus a stationary clot.

tissues systems of cells working together to perform specialized tasks. Examples are muscles, nerves, blood, and bone.

tocopherol (tuh-KOFF-er-all) a kind of alcohol. The active form of vitamin E is alpha-tocopherol.

tofu (TOE-foo) a curd made from soybeans, rich in protein and often rich in calcium and variable in fat content; used in many Asian and vegetarian dishes in place of meat.

tolerance limit the maximum amount of a residue permitted in a food when a pesticide is used according to label directions.

toxicity the ability of a substance to harm living organisms. All substances are toxic if high enough concentrations are used.

trabecular (tra-BECK-you-lar) bone the weblike structure composed of calcium-containing crystals inside a bone's solid outer shell. It provides strength and acts as a calcium storage bank.

trace minerals essential mineral nutrients found in the human body in amounts less than 5 grams.

training regular practice of an activity, which leads to physical adaptations of the body, with improvements in flexibility, strength, or endurance.

trans-fatty acids fatty acids with unusual shapes that can arise when polyunsaturated oils are hydrogenated.

transgenic organism an organism that grows from an embryonic, stem, or germ cell into which a new gene has been inserted. The organism carries the new gene in all of its cells.

triglycerides (try-GLISS-er-ides) one of the three main classes of dietary lipids and the chief form of fat in foods. A triglyceride is made up of three units known as fatty acids and one unit called glycerol.

trimester one-third of gestation, about 13 to 14 weeks.

tripeptides (try-PEP-tides) protein fragments that are three amino acids long (tri means "three").

turbinado (ter-bih-NOD-oh) sugar raw sugar from which the filth has been washed; legal to sell in the United States.

ulcers erosions in the topmost, and sometimes underlying, layers of cells that form linings. Ulcers of the digestive tract commonly form in the esophagus, stomach, or upper small intestine.

ultrahigh temperature (UHT) short-time exposure of a food to temperatures above those normally used, to sterilize it.

unbleached flour a beige-colored endosperm flour with texture and nutritive qualities that approximate those of regular white flour.

underwater weighing a measure of density and volume used to determine body fat content.

unsaturated fatty acids a fatty acid that lacks some hydrogen atoms and has one or more points of unsaturahon. An unsaturated fat is a triglyceride that contains one or more unsaturated fatty acids.

unspecified eating disorders eating disorders that do not meet the criteria for specific eating disorders previously defined.

urea (yoo-REE-uh) the principal nitrogen-excretion product of metabolism, generated mostly by removal of amine groups from unneeded amino acids or from amino acids being sacrificed to a need for energy.

urethane a carcinogenic compound that commonly forms in alcoholic beverages.

USDA (U.S. Department of Agriculture) the federal agency responsible for enforcing standards for the wholesomeness and quality of meat, poultry, and eggs produced in the United States; conducting nutrition research; and educating the public about nutrition.

uterus (YOO-ter-us) the womb, the muscular organ within which the infant develops before birth.

variety the dietary characteristic of consuming a wide selection of foods—the opposite of monotony.

vegans (VAY-guns, VEJ-uns) people who include no animal derived products in their diets. These people are also called strict vegetarians.

vegetarians people who exclude from their diets animal flesh and possibly animal products such as milk, cheese, and eggs. See also facto-, lacto-ovo-, semivegetarian, and vegan.

veins blood vessels that carry used blood with the carbon dioxide from the tissues back to the heart.

very low sodium on a food label, 35 mg or less sodium per serving.

villi (VILL-ee, VILL-eye) fingerlike projections of the sheets of cells that line the intestinal tract. The villi make the surface area much greater than it would otherwise be (singular: villus).

visceral fat fat stored within the abdominal cavity in association with the internal abdominal organs. Also called introabdominal fat.

vitamin B12 a B vitamin that enables folate to get into cells and also helps maintain the sheath around nerve cells. Vitamin Bl2's scientific name, not often used, is cyanocobalamin.

vitamin B6 a B vitamin needed in protein metabolism. Its three active forms are pyridoxine, pyridoxal, and pyridoxamine.

vitamins organic compounds that are vital to life and indispensable to body function, but are needed only in minute amounts; noncaloric essential nutrients.

V02 max the maximum rate of oxygen consumption by an individual (measured at at sea level).

voluntary activities intentional activities (such as walking, sitting, running) conducted by voluntary muscles.

wasting the progressive, relentless loss of the body's tissues that accompanies certain diseases and shortens survival time.

water balance the balance between water intake and water excretion, which keeps the body's water content constant.

water intoxication the rare condition in which body water content is too high. Symptoms are headache, muscular weakness, lack of concentration, poor memory, and loss of appetite.

weight cycling repeated rounds of weight loss and subsequent regain, with reduced ability to lose weight with each attempt. Also called yo-yo dieting.

well water water drawn from ground water by tapping into an aquifer.

wheat flour any flour made from wheat, including white flour.

whey the liquid that remains after milk has coagulated (see also casein).

white flour an endosperm flour that has been refined and bleached for maximum softness and whiteness.

white sugar pure sucrose, produced by dissolving, concentrating, and recrystallizing raw sugar.

WHO (World Health Organization) an international agency that, among other responsibilities, develops standards to regulate pesticide use. A related organization is the FAO (Food and Agricultural Organization).

whole foods see basic foods.

whole grain refers to a grain milled in its entirety (all but the husk), not refined.

whole milk full-fat cow's milk.

whole-wheat flour flour made from whole-wheat kernels; a whole-grain flour.

witch hazel leaves or bark of a witch hazel tree; not proved to have healing powers.

xerophthalmia (ZEER-ahf-THALL-me-uh) hardening of the cornea of the eye in advanced vitamin A deficiency that can lead to blindness (xero means "dry"; ophthalm means "eye").

xerosis drying of the cornea; a symptom of vitamin A deficiency.

zygote (ZYE-goat) the term that describes the product of the union of ovum and sperm during the first two weeks after fertilization.