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Glossary: Words M to Z
MACROBIOTIC VEGETARIAN: persons who consume vegan or
vegetarian diets which also involve non-animal food avoidances and extensive use
of unprocessed, unrefined foods, especially brown rice and other whole grains.
MACROCYTIC ANEMIA: anemia characterized by larger than normal RBCs, increased
mean corpuscular volume, and mean corpuscular hemoglobin.
MACROMINERAL: a naturally occurring, homogeneous, inorganic substance required
by humans in amounts of 100 mg or more per day; calcium, phosphorus, magnesium,
sulfur, sodium, chloride, potassium.
MALABSORPTION: abnormal or inadequate gastrointestinal absorption of nutrients.
MALTASE: the intestinal enzyme that hydrolyzes maltose into glucose units.
MALTOSE (MALT SUGAR): a disaccharide composed of two glucose units.
MANNITOL: a sugar alcohol that exists in fruit, is poorly digested, and yields
about half as many calories as glucose.
MARASMUS: a chronic form of protein-energy malnutrition in which the deficiency
is primarily of energy.
MEDIUM-CHAIN FATTY ACID: a fatty acid with 8 to 12 carbons.
MEDIUM-CHAIN TRIGLYCERIDES: triacylglycerols with fatty acids of 8 to 12 carbons
in length that are short enough to be absorbed directly into the portal blood.
MEGALOBLASTIC ANEMIA: anemia characterized by the presence of large, immature,
abnormal RBC progenitors in the bone marrow; characteristic of a folic acid or
vitamin B12 deficiency.
MELANIN: a dark pigment found in the skin, retina, and hair.
MENADIONE: synthetic form of vitamin K.
MENAQUINONE: vitamin K synthesized by bacteria.
MENOPAUSE: the period of cessation of menstruation, occurring around age 50.
METABOLIC RATE: an expression of the rate at which oxygen is used by the body.
METABOLISM: the chemical processes consisting of anabolism and catabolism;
responsible for the production of energy, biosynthesis of important substances,
and degradation of various compounds.
METALLOTHIONEIN: an abundant nonenzymatic zinc-containing protein.
METHYL: CH3, derived from methane and occurring in many important organic
compounds.
MICELLE: a particle containing lipids and bile salts that moves fatty acids from
the intestinal lumen to the intestinal mucosa for absorption.
MICROCYTIC ANEMIA: anemia characterized by smaller than normal erythrocytes and
less circulating hemoglobin; usually caused by a deficiency of iron.
MICROMINERAL (Trace Element): a naturally occurring, homogeneous, inorganic
substance required by humans in amounts of less than 100 mg per day.
MICROVILLI: projections from the membranes of the cells of the villi; area of
nutrient absorption.
MILK-ALKALI SYNDROME: a condition of alkalosis brought about by very excessive
consumption of milk, calcium-containing antacids, or other alkaline substances;
most likely to occur in older people with peptic ulcer.
MILK THISTLE: a botanical that has silymarin as its principle active constituent
and is known for its hepatoprotective characteristics.
MINERALOCORTICOID: adrenocortical hormones that regulate electrolyte balance;
aldosterone is the most potent.
MITOCHONDRIA: organelles that are the principal energy source of the cell, and
contain the cytochrome enzymes of terminal electron transport, and the enzymes
of the Krebs cycle, fatty acid oxidation (beta-oxidation), and oxidative
phosphorylation.
MODIFIED FOOD STARCH: starch that has been treated with a variety of chemicals
so that it can still function as a thickening agent but can also form solutions
with cold water that maintain stability in the presence of acid, freezing, and
thawing.
MOLECULE: the simplest structural unit that displays the characteristic physical
and chemical properties of a compound.
MONOGLYCERIDE: a lipid with one fatty acid attached to the glycerol molecule.
MONOSACCHARIDE: a sugar incapable of being digested to a simpler form; glucose,
fructose, galactose.
MONOUNSATURATED FATTY ACID (MUFA): a fatty acid containing one double bond.
MORBID OBESITY: a state of adiposity in which body weight is 100% above the
idea.
MUCOPOLYSACCHARIDE: a compound comprising protein and carbohydrate found in
connective tissue, collagen, and bone matrix; a more modern term is
glycosaminoglycan.
MUCOUS MEMBRANE: the membrane lining all bodily channels that communicate with
the air, such as the respiratory, and alimentary tracts, the glands of which
secrete mucus.
MUCUS: a mucopolysaccharide (a relative of carbohydrate) secreted as a
protective, lubricant coating by glands in the mucous membrane.
MUSCULAR DYSTROPHY: an inherited disease in which the muscles gradually weaken.
MUTAGENIC: capable of producing changes in DNA or chromosomal structure,
resulting in permanent alteration in the genetic information carried by DNA.
MYALGIA: pain in a muscle or muscles.
MYOCARDIAL INFARCTION: heart attack; condition resulting from the occlusion of a
coronary artery and interruption of the blood supply to cardiac tissue.
MYOGLOBIN: a ferrous protoporphyrin protein, similar to hemoglobin, that is
present in muscle and stores oxygen.
MYOPATHY: any disease of the muscle.
MYXEDEMA: a disease caused by decreased activity of the thyroid gland in adults;
characterized by dry skin, swellings around the lips and nose, mental
deterioration, and a subnormal basal metabolic rate.
NECROTIZING ENTEROCOLITIS: a disease seen in infants which involves degeneration
of a part of the intestinal tract.
NEOPLASM: an abnormal new growth of tissue; tumor.
NEPHRITIS: kidney disease resulting in some loss of function.
NEPHROSIS: any disease of the kidney, but especially when characterized by
purely degenerative lesions of the renal tubules.
NET PROTEIN UTILIZATION (NPU): a measure of protein quality; the amount of
protein nitrogen that is retained from a given amount of protein nitrogen eaten.
NEUROGLYCOPENIA: neurological symptoms of hypoglycemia that are related to an
insufficient supply of glucose to the brain.
NEUROPATHY: noninflammatory lesions related to functional disturbances in the
peripheral nervous system.
NEUROTRANSMITTER: any chemical that results in the transmission of nerve
impulses between neurons in the brain and nerves.
NEUTROPENIA: a reduction in the blood neutrophil (granulocyte) count often
leading to an increased susceptibility to bacterial and fungal infections.
NEUTROPHIL: a granular leukocyte.
NIACIN EQUIVALENT (NE): Equals the amount of preformed niacin in food, plus the
amount that can be converted from the amino acid, tryptophan.
NICOTINAMIDE: niacinamide; a form of vitamin B3 that doesn’t cause a flush.
NICOTINIC ACID: niacin; vitamin B3.
NIGHTBLINDNESS: poor vision in dim light or at night as a result of vitamin A
deficiency.
NITROGEN BALANCE: relating to protein, it is the amount of nitrogen consumed as
compared with the amount of nitrogen excreted in a given period of time.
NITROSAMINES: carcinogenic derivatives of nitrites that may be formed in the
stomach when nitrites combine with amines.
NONHEME IRON: the form of iron found in eggs, grains, vegetables, and fruits,
and which is less well absorbed than heme iron.
NON-INSULIN-DIABETES MELLITUS (Type 2): diabetes characterized by a gradual
onset with minimal or no symptoms of metabolic disturbance and no requirement
for exogenous insulin to prevent ketonuria and ketoacidosis; usually occurs
after 30 years of age.
NOREPINEPHRINE: hormone produced by the adrenal medulla that increases blood
pressure by constricting the blood vessels; released predominantly in response
to hypotension.
NORMOCHROMIC: normal color.
NORMOCYTIC: normal size.
NONSTEROIDAL ANTI-INFLAMMATORY DRUG (NSAID): type of drug used to treat
osteoarthritis, rheumatoid arthritis, and other pain; available over the counter
as aspirin, acetaminophen (e.g., Tylenol), proprionic acids (e.g., Ibuprofen),
and other classes.
NUCLEIC ACID: a member of either of two groups of complex compounds found in all
living cells, and composed of purines, pyrimidines, carbohydrates, and
phosphoric acid.
NUCLEOPROTEIN: any of a group of substances found in all living cells and
viruses, and composed of a protein and a nucleic acid.
NUTRIENT: a substance obtained from food and used in the body to promote growth,
maintenance, and/or repair. The six classes of nutrients are carbohydrate, fat,
protein, vitamins, minerals, and water.
NUTRIENT DENSITY: the concentration of nutrients in a food. The higher the
nutrient density, the higher the food quality.
OBESITY: a state of adiposity in which body fatness is at least 20% above the
ideal.
OCCLUSION: the shutting off of the blood flow in an artery.
OLEIC ACID: an 18-carbon, monounsaturated fatty acid.
OLIGOSACCHARIDE: a carbohydrate that upon hydrolysis yields 3 to 10
monosaccharide units.
OMEGA NUMBER: the number of the carbon molecule with the first double bond, as
counted from the methyl end of the fatty acid; for example, written as n-3 or
ω-3 (or n-6 or ω-6).
OMEGA-3 FATTY ACIDS (n-3 or ω-3): fatty acids with the first double bond located
at the third carbon from the methyl end of the hydrocarbon chain; most important
are alpha-linolenic acid (ALA) found in flax seed oil, and its derivatives
eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA) found in fish oils.
OMEGA-6 FATTY ACIDS (n-6 or ω-6): fatty acids with the first double bond located
at the sixth carbon from the methyl end of the hydrocarbon chain; most important
is gamma-linolenic acid (GLA) found in evening primrose and borage seed oils.
OPSIN: the protein of the visual pigments. Vitamin A is a helper nutrient,
attached to opsin to form the pigment, rhodopsin.
ORAL GLUCOSE-LOWERING MEDICATIONS: drugs, administered orally, that are used to
control or lower blood glucose levels, including first- and second-generation
sulfonylureas, biguanides, alpha-glucosidase inhibitors, thiazolidinediones, and
meglitinide.
ORGANELLE: a specialized part of a cell that resembles and functions as an
organ.
ORGANIC: denoting chemical substances containing carbon.
OSSIFICATION: the natural process of bone formation.
OSTEOARTHRITIS (Degenerative Arthritis): noninflammatory degenerative joint
disease occurring mainly in older persons, characterized by degeneration of the
joint cartilage, hypertrophy of bone at the margins, and changes in the synovial
membrane.
OSTEOMALACIA: a condition of impaired mineralization of the bones caused by
vitamin D and calcium deficiencies.
OSTEOPENIA: insufficiency of bone resulting from reduced production or increased
breakdown of the bone.
OSTEOPOROSIS: a loss of bone density to the point that the skeleton is unable to
sustain ordinary stresses, and fractures develop.
OXALIC ACID: an organic acid found in certain leafy vegetables (rhubarb,
spinach, chard, beet greens) that binds with calcium and inhibits its absorption
from these foods.
OXIDANT: the substance that is reduced and that, therefore, oxidizes the other
component of an oxidation-reduction system; may cause the production of free
radicals.
OXIDATION: a reaction in which electrons are removed from a molecule. Usually
the combination of a substance with oxygen.
OXIDATIVE STRESS: the balance between the formation of toxic, free radical
oxidation products and the biochemical reduction reactions that convert these
compounds to benign end products.
PANCREATIC LIPASE: an enzyme in pancreatic juice that hydrolyzes the ester
linkages between fatty acids and glycerol.
PARASYMPATHETIC NERVOUS SYSTEM: the part of the autonomic nervous system that, in
general, inhibits or opposes the physiological effects of the sympathetic
nervous system, as in tending to stimulate digestive secretions, slowing the
heart, and dilating blood vessels.
PARATHYROID HORMONE (PTH): controls the calcium level in the blood. Secreted by
the parathyroid gland.
PARENTERAL NUTRITION: the delivery of nutrients directly into the circulation;
can be either peripheral or central, total or supplemental.
PARIETAL CELLS: large cells scattered along the walls of the stomach that
secrete the hydrochloric acid in gastric juice.
PASSIVE DIFFUSION: the random movement of particles through openings in cellular
membranes depending on electrochemical and concentration gradients.
PECTIN: a noncellulose polysaccharide made up of units of a derivative of
galactose that is found in fruit.
PELLAGRA: niacin deficiency disease.
PEPSIN: a digestive enzyme found in gastric juice that catalyzes the breakdown
of protein to peptides.
PEPTIC ULCER: an eroded lesion in either the esophageal, gastric, or duodenal
mucosa resulting from the action of acid in gastric juice.
PEPTIDE: any compound of low molecular weight that yields two or more amino
acids on hydrolysis; constituent part of proteins.
PERISTALSIS: the movement of the intestine, or other tubular structure,
characterized by waves of alternate circular contraction and relaxation of the
tube by which the contents, such as food, are propelled onward.
PERNICIOUS ANEMIA: a macrocytic, megaloblastic anemia caused by a deficiency of
vitamin B12.
PEROXIDATION: the addition of an oxygen atom at a double bond in an unsaturated
fatty acid; can occur in the body or in food; can be caused by certain free
radicals.
pH: the concentration of hydrogen ions (H+); the lower the pH, the stronger the
acid.
PHENOLS: a class of phytochemicals hat function in plants a blue, blue-red, and
violet pigments and that provide protection against oxidative damage.
PHENYLKETONURIA (PKU): an inherited disease caused by a lack of an enzyme
necessary for converting the amino acid, phenylalanine, into the amino acid,
tyrosine.
PHLEBITIS: inflammation of a vein; marked by infiltration of the coats of the
vein and by the formation of a thrombus.
PHOSPHOLIPID: a triglyceride in which one of the fatty acids is replaced by a
substance containing phosphorus; lecithin is a common phospholipid.
PHYLLOQUINONE: vitamin K from plants.
PHYTIC ACID (Phytate): a phosphorus-containing compound found in the outer husks
of cereal grains that binds with calcium and inhibits its absorption.
PHYTOCHEMICALS: biologically active, naturally occurring substances in plants
that act as natural defense systems in plants and that show potential for
reducing risk for cancer and cardiovascular disease.
PHYTOESTROGENS: phytochemicals that are non-steroidal estrogens of dietary
origins; structurally similar to estrogens, they act in the body as weak
estrogens and anti-estrogens.
PICA: an abnormal craving to consume unusual substances such as clay, chalk,
laundry starch, and dirt.
PLACEBO: an inert, harmless medication given to provide comfort and hope.
PLAQUE: a patch or small differentiated area on a body surface (e.g., skin,
mucosa, or arterial endothelium) or on the cut surface of an organ such as the
brain. In terms of heart disease, refers to mounds of lipid material, mixed with
smooth muscle cells and calcium, which are lodged in the artery walls.
PLASMA: the clear, yellowish fluid portion of blood, lymph, or intramuscular
fluid in which cells are suspended.
POLYDIPSIA: chronic, excessive thirst, as seen in diabetes mellitus or diabetes
insipidus.
POLYMER: any of numerous natural and synthetic compounds of usually high
molecular weight consisting of up to millions of repeated linked units, each a
relatively light and simple molecule.
POLYP: in the colon, a mushroom-like growth that can progress to cancer.
POLYPEPTIDE: ten or more amino acids bonded together by peptide bonds.
POLYSACCHARIDE: a carbohydrate that upon hydrolysis yields more than 10
monosaccharide units.
POLYUNSATURATED FATTY ACID (PUFA): a fatty acid containing two or more double
bonds; common in vegetable oils.
POLYURIA: excessive urination; common in diabetes.
POSTMENOPAUSAL OSTEOPOROSIS (Type I): a loss of density primarily involving the
trabecular bone and characterized by fractures of the distal radius and crush
fractures of the lumbar vertebrae.
POSTPRANDIAL: after a meal.
POSTPRANDIAL (REACTIVE) HYPOGLYCEMIA: low blood glucose within 2 to 5 hours
after eating.
PRECURSOR: a substance from which another, usually more active or mature
substance is formed.
PREBIOTICS: nondigestible food products that stimulate the growth of symbiotic
bacterial species already present in the colon; they help to improve the health
of the host.
PREECLAMPSIA: the early stage of pregnancy-induced hypertension.
PREFORMED VITAMIN A: form of vitamin A present in animal foods.
PROBIOTICS: microbial foods or supplements that can be used to change or
reestablish the intestinal flora and improve the health of the host.
PROGRAM THEORY: a theory of aging that proposes that cells are capable of
reproducing themselves for a programmed, finite number of times, after which
they die.
PROMOTER: a substance that does not initiate cancer, but that favors its
development once the initiating event has taken place.
PROSTACYCLIN: prostaglandin I2; a potent natural inhibitor of platelet
aggregation and a powerful vasodilator.
PROSTAGLANDIN: any of a class of physiologically active hormone-like substances
present in many tissues, with effects such as vasodilation, vasoconstriction,
stimulation of intestinal or bronchial smooth muscle, uterine stimulation, and
antagonism to hormones influencing lipid metabolism; produced in the body from
omega-3 (n-3) and omega-6 (n-6) polyunsaturated fatty acids.
PROSTHETIC GROUP: a coenzyme that is physically part of its enzyme.
PROTEASE: an enzyme that breaks peptide bonds found in protein.
PROTEIN: a complex nitrogenous compound made up of amino acids in peptide
linkages; involved in structures, hormones, enzymes, muscle contraction,
immunological response.
PROTEIN EFFICIENCY RATIO (PER): a measure of protein quality; the grams of
weight gained by growing animals per gram of protein fed.
PROTEIN ENERGY MALNUTRITION: a class of clinical disorders resulting from
varying combinations and degrees of protein and energy deficiency; infants and
children are particularly vulnerable; early symptoms include loss of appetite,
easy fatigability, loss of weight, and retarded growth. Also called
protein-calorie malnutrition.
PROTEIN-SPARING ACTION: the contribution of nutrients from carbohydrate and fat
that allow amino acids to be used to build body proteins.
PROTEIN TURNOVER: the exchange of amino acids among organs within the body.
PROTEOLYTIC: relating to or effecting the decomposition of protein; proteolytic
enzymes digest food proteins.
PROTHROMBIN: the protein in blood plasma needed for blood clotting.
PROVITAMIN: a dietary precursor to an active form of a vitamin.
PSORIASIS: a chronic, noncontagious skin disease characterized by inflammation
and white, scaly patches.
PTEROYLGLUTAMIC ACID: folic acid.
PURINES: the nitrogenous bases, adenine and guanine, which are constituents of
nucleoproteins, whose metabolic end-product is uric acid.
PUTREFACTION: enzymatic decomposition of proteins with the production of
foul-smelling compounds, such as hydrogen sulfide, ammonia, and mercaptans.
PYRIDOXAL PHOSPHATE (PLP): a coenzyme containing vitamin B6 that is necessary
for transamination reactions.
PYRUVATE: the end product of glycolysis; can be converted into lactate or acetyl
CoA.
RANCID: having a musty, rank taste or smell due to fats that have oxidized and
decomposed with the liberation of fatty acids.
REACTIVE POSTPRANDIAL HYPOGLYCEMIA: abnormally low concentration of blood
glucose within 2 to 5 hours after eating.
RECOMMENDED DIETARY ALLOWANCES (RDA): recommendations for the average amounts of
nutrients that should be consumed daily by healthy people in the US.
RECEPTOR SITE: a chemical structure on the cell membrane where a hormone or
antigen binds.
RED BLOOD CELL (RBC): hemoglobin-enriched blood cells responsible for the
transport of oxygen from the lungs to tissues.
REDOX: oxidation-reduction.
REDUCED: altered by a chemical change involving a gain of electrons.
REFERENCE DAILY INTAKES (RDIs): set of dietary references for food labels based
on the 1968 RDAs for vitamins and minerals, this term replaces the U.S. RDA
previously used with nutrition labeling on food products.
REFERENCE PROTEIN: egg protein; used by FAO/WHO as a standard against which to
measure the quality of other proteins.
REFINED FOOD: a food from which the coarse parts have been removed. With respect
to grains, a product from which the bran, germ, and chaff have been removed.
RENAL INSUFFICIENCY: inability of the kidney to excrete waste materials and
conserve water, electrolytes, and other important molecules to the extent
needed.
RESORPTION (Bone): the loss of bone matrix and mineral.
RESTING ENERGY EXPENDITURE (REE): the amount of energy used by a person in 24
hours when at rest, 3 to 4 hours after a meal.
RESTING METABOLIC RATE (RMR): the energy expended by a person at rest, expressed
as kcal per kg of body weight per hr.
RETINA: the layer of light-sensitive cells lining the back of the inside of the
eye; consists of rods and cones.
RETINAL: the aldehyde form of vitamin A, active in the eye.
RETINOL: the form of vitamin A with the highest biologic activity.
RETINOL EQUIVALENT: a measure of the vitamin A activity in foods.
RHEUMATOID ARTHRITIS: chronic inflammatory systemic disease primarily of the
joints, marked by changes in the synovial membranes and joint structures, and by
atrophy and rarefaction of the bones.
RHODOPSIN: the light-sensitive pigment of the rods in the retina.
RIBONUCLEIC ACID (RNA): a nucleic acid found in all cells, consisting of ribose,
phosphate, and the bases adenine, guanine, cytosine, and uracil.
RICKETS: a disease of abnormal ossification of the bone caused by a deficiency
of vitamin D; occurs in growing children.
RODS: the cells of the retina that respond to dim light and convey black and
white vision.
ROTATION DIET: an eating plan in which several foods known to cause allergic
reactions or which are not tolerated, are eaten on separate days, and then only
every fourth or fifth day for each food.
SACCHARIDES: carbohydrates; classified as mono-, di-, tri- and polysaccharides
according to the number of monosaccharide groups composing them.
SALMONELLOSIS: any disease caused by a salmonella infection, which may manifest
as food poisoning with acute gastroenteritis, vomiting, and diarrhea.
SALT-SENSITIVE HYPERTENSION: hypertension that appears to respond to salt
intake.
SAPONIFICATION: the process of hydrolyzing fats into soaps and glycerol by the
addition of alkali.
SATIETY: the condition of being full or gratified beyond the point of
satisfaction.
SATURATED FATTY ACID (SFA): a fatty acid with the formula CnH2nO2 that has no
double bonds and that contains all the hydrogen it can hold.
SAW PALMETTO: a botanical from which lipophilic extracts of berries are used as
an adjunctive treatment for benign prostatic hyperplasia.
SCURVY: vitamin C deficiency disease.
SECRETIN: a hormone released from the duodenal wall into the bloodstream, which
stimulates the pancreas to secrete water and bicarbonate and inhibits gastrin
secretion.
SENILE DEMENTIA OF THE ALZHEIMER TYPE (SDAT): degenerative brain disease
occurring beyond middle age and resulting in changes in behavior and in loss of
memory, cognitive function, and speech.
SENSITIZATION: exposure to an antigen or allergen that results in the
development of hypersensitivity.
SEROTONIN: a neurotransmitter produced from the amino acid, tryptophan, that
assists in relaxation and sleep.
SERUM: the cell-free fluid that remains after the fibrin clot and blood cells
are removed.
SET-POINT THEORY: the theory that a certain body weight is physiologically
normal for each person, and that the body will resist deviation from that
weight.
SHORT-CHAIN FATTY ACID: a fatty acid with 6 carbons or less.
SIMPLE CARBOHYDRATE: a simple form of sugar (mono- and disaccharides): glucose,
fructose, galactose, sucrose, lactose, maltose, and other “oses”.
SIMPLE PROTEINS: proteins such as globulins and albumins that yield only amino
acids on hydrolysis.
SOFT WATER: water containing a high sodium concentration.
SOLUBLE FIBER: pectins, gums, mucilages, and some hemicelluloses that form gels
with water, and contribute to the lowering of serum cholesterol levels.
SOMOGYI (REBOUND) EFFECT: hypoglycemia followed by “rebound” hyperglycemia
caused by an overproduction of counter-regulatory hormones; insulin does should
not be increased at this time.
SORBITOL: a sugar alcohol occurring naturally in fruits; in mammals is found in
some tissues such as the lens of the eye.
SPASTIC COLON: increased or uncontrolled contractions of the colon; irritable
bowel syndrome.
SPORTS ANEMIA: a transient anemia seen in heavily training athletes
characterized by a decrease in the RBC count, hemoglobin concentration, and
packed cell volume, but with normal RBC morphology.
STARCH: a polysaccharide, composed of glucose, found only in plants. It occurs
in both the amylose form and the amylopectin form.
STEATORRHEA: excessive amounts of fat in the feces, as seen in malabsorption
syndromes.
STEROL: a compound composed of carbon, hydrogen, and oxygen atoms arranged in
rings like those of cholesterol.
ST. JOHN’S WORT: a botanical that is sometimes used as an antidepressant, with
applications for mild to moderate depression.
STOMATITIS: inflammation of the oral mucosa or soft tissues of the mouth.
SUCRASE: the intestinal enzyme that hydrolyzes sucrose to glucose and fructose.
SUCROSE: ordinary table sugar; a disaccharide composed of glucose and fructose
found in sugar cane, sugar beets, molasses, maple syrup, maple sugar, fruit,
vegetables, and honey.
SUGAR ALCOHOLS: sugar-like substances (mannitol, sorbitol, xylitol) which are
derived from fruits or dextrose; they are absorbed slower and metabolized
differently than other sugars, and are not readily used by ordinary mouth
bacteria.
SUPEROXIDE DISMUTASE (SOD): an enzyme protecting against damage from
accumulating superoxide radical by reducing the radical to hydrogen peroxide and
oxygen; requires copper, zinc, or manganese.
SYMPATHETIC NERVOUS SYSTEM: the portion of the autonomic nervous system that
opposes the parasympathetic nervous system.
SYNAPSE: the gap between one nerve cell and the next nerve cell it communicates
with. Neurotransmitters are the agents that facilitate the communication.
SYNDROME: a group of signs and symptoms that collectively indicate or
characterize a disease, psychological disorder, or other abnormal condition.
SYNDROME X: a cluster of metabolic disorders, including non-insulin-dependent
diabetes mellitus, hypertension, and dyslipidemia, that is characterized by
insulin resistance.
SYNERGIST: a structure, agent, or physiologic process that aids the action of
another.
SYNOVIAL FLUID: a clear, viscid, lubricating fluid secreted by membranes in
joint cavities, sheaths of tendons, and bursae.
SYNTHESIS: the process of building up; the formation of complex compounds from
simpler compounds.
TACHYCARDIA: rapid heart rate, usually above 100 beats per minute.
TERATOGEN: an agent or disease state capable of causing congenital malformations
and other serious deviations from normal fetal development.
TETANY: muscle twitching, spasms, and eventually convulsions that can be caused
by low levels of blood calcium or magnesium.
THERMIC EFFECT OF FOOD (TEF): the fraction of the total energy expenditure
contributed by the processes of digestion, absorption, and metabolism of food;
the increase in metabolism that is stimulated by eating.
THERMOGENESIS: the production of heat in organisms.
THIOL: a sulfur-containing phytonutrient found in cruciferous vegetables.
THROMBOXANE: an eicosanoid that is a potent inducer of platelet aggregation;
also a vasoconstrictor, it is a physiologic antagonist to prostacyclin.
THROMBUS: a stationary clot; can grow large enough to close off a blood vessel.
THYROXIN: an iodine-containing hormone secreted by the thyroid gland to regulate
the rate of cell metabolism (basal metabolic rate).
TISSUE: a collection of similar cells and the intercellular substances
surrounding them. There are four basic tissues in the body: 1) epithelium; 2)
the connective tissues, including blood, bone, and cartilage; 3) muscle tissue;
and 4) nerve tissue.
TOCOPHEROL: vitamin E.
TOCOPHEROL EQUIVALENT (TE): basis for expressing the vitamin E activity of
compounds as compared to the activity of 1 mg (1.49 I.U.) of alpha-tocopherol
(natural vitamin E).
TOLERABLE UPPER INTAKE LEVEL (UL): the maximum level of daily nutrient intake
that is unlikely to impose risks of adverse health effects to almost all of the
individuals in the general population.
TOTAL ENERGY EXPENDITURE (TEE): the sum of the resting energy expenditure,
energy expended in physical activity, and the thermic effect of food; the energy
expended by an individual in 24 hours.
TRABECULAR BONE (Cancellous Bone): the spongy bone in the knobby ends of the
long bones, the iliac crest, scapula, and vertebrae.
TRANSAMINATION: the transfer of an amino group from an alpha-amino acid to an
alpha-keto acid; requires vitamin B6.
TRANS FATTY ACIDS: stereoisomers of the naturally occurring cis fatty acids;
artifacts of the hydrogenation process; found in margarines and vegetable
shortenings.
TRANSFERRIN: a protein synthesized in the liver that transports iron in the
blood to the erythroblasts for use in heme synthesis.
TRANSIT TIME: the interval between the time when food is ingested and when the
residue of that digested food is evacuated from the rectum.
TRANSKETOLASE: an enzyme essential in carbohydrate metabolism that requires
thiamin (B1) as a coenzyme.
TRIGLYCERIDE (TRIACYLGLYCEROL): a lipid consisting of three fatty acid chains
bound (esterified) to a glycerol molecule.
TRIPEPTIDE: three amino acids bonded together by peptide bonds.
TROPHIC EFFECTS: the stimulation of cell reproduction and enlargement.
TYRAMINE: an amino acid that can be synthesized in the body from tyrosine and
stimulates the release of epinephrine and norepinephrine; also found in various
food products, including aged cheeses and red wine; may cause migraine
headaches.
TRYPTOPHAN: an amino acid that serves as the metabolic precursor of niacin.
TYPE 1 DIABETES: current term for insulin-dependent diabetes mellitus (IDDM).
TYPE 2 DIABETES: current term for non-insulin-dependent diabetes mellitus (NIDDM).
ULCERATIVE COLITIS: chronic, recurrent ulceration of the mucosa and submucosa in
the colon.
UNDERWEIGHT: a body weight 15% to 20% below the accepted weight standard.
UREA: the chief nitrogenous end-product of protein metabolism, and the chief
nitrogenous constituent of urine.
UREMIA: an excess of urea in the blood.
URETHRA: the tube through which urine from the bladder passes out of the body.
URP (Unique Radiolytic Product): a product formed during the irradiation of
food.
URTICARIA: a skin condition characterized by intensely itching welts; caused by
allergic reactions to internal or external agents, by infections, or by psychic
stimuli.
VALERIAN: a botanical that has adjunctive therapeutic application as a sleep aid
and that acts on the central nervous system.
VASOCONSTRICTOR: agent that causes the blood vessels to decrease in diameter.
VASODILATOR: agent that causes blood vessels to increase in diameter.
VEGAN: a person who consumes only foods of plant origin and excludes all animal
protein from the diet.
VEGETARIAN: a person who consumes primarily plant foods (grains, legumes,
vegetables, and fruits) and eliminates meats, poultry, and fish from the food
pattern; dairy foods and eggs may be consumed.
VEIN: a vessel that carries blood back to the heart.
VERY LOW-DENSITY LIPOPROTEIN (VLDL): a triglyceride-rich endogenous complex of
lipid and protein for transport in the blood.
VILLI: finger-like projections from the folds of the small intestine.
VITAMER: one of multiple forms of a vitamin.
VITAMIN: organic substances found in food in minute quantities which are
essential for normal growth and metabolism, and that cannot be synthesized by
the body.
WATER-SOLUBLE VITAMINS: vitamin C and the B-complex vitamins; those which
dissolve in water.
WHEY PROTEINS: the proteins remaining in the watery fraction of milk after the
curd and cream have been removed.
WHITE ADIPOSE TISSUE: repository for triglyceride; a cushion to protect body
organs and an insulator to preserve body heat.
WHOLE GRAIN: a grain that retains much of the material of its outside layers,
except the chaff.
YO-YO EFFECT: the process of losing and gaining eight several times throughout a
lifetime; characterized by a greater fatness after each cycle.
XERODERMA: a dry, rough, discolored state of the skin, with the formation of a
scaly desquamation.
XEROPHTHALMIA: in the eye, the collective symptoms of vitamin A deficiency.
XEROSIS: abnormal dryness of the skin, mucous membranes, or conjunctiva.
XYLITOL: a noncariogenic (doesn’t cause tooth decay) sugar alcohol absorbed one
fifth as fast as glucose, and often used in sugarless chewing gum.
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