Nutrition: Concepts and Controversies (16th Edition)

Essential vocabulary flashcards covering key definitions, dietary standards, metabolic pathways, and physiological concepts from Nutrition: Concepts & Controversies (16th Edition).

Nutrition

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

Malnutrition

Any condition caused by excess or deficient food energy or nutrient intake or by an imbalance of nutrients.

Energy-Yielding Nutrients

The nutrients the body can use for energy: carbohydrate ($4\text{ cal/g}$), fat ($9\text{ cal/g}$), and protein ($4\text{ cal/g}$).

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.

Phytochemicals

Bioactive compounds in plant-derived foods that confer color, taste, and other characteristics and may alter physiological processes in the body.

Dietary Pattern

The combination of foods and beverages that constitute an individual's complete dietary intake over time; a person's habitual diet.

Nutrient Density

A measure of nutrients provided per calorie of food; a nutrient-dense food supplies needed vitamins, minerals, and other nutrients with relatively few calories.

Dietary Reference Intakes (DRI)

A set of five lists of nutrient intake standards for healthy people in the United States and Canada: EAR, RDA, AI, UL, and AMDR.

Recommended Dietary Allowances (RDA)

Nutrient intake goals for individuals; the average daily intake level that meets the needs of nearly all ($97\%$ to $98\%$) healthy people in a particular sex and life stage group.

Adequate Intakes (AI)

Nutrient intake goals set when scientific data are insufficient to allow establishment of an RDA value; assumed to be adequate for healthy individuals.

Tolerable Upper Intake Levels (UL)

The highest average daily nutrient intake levels that are likely to pose no risk of toxicity to almost all healthy individuals in a given population group.

Estimated Average Requirements (EAR)

The average daily nutrient intake estimated to meet the requirement of half of the healthy individuals in a specific sex and life stage group; used in nutrition research and policy making.

Acceptable Macronutrient Distribution Ranges (AMDR)

Values for carbohydrate ($45\%$ to $65\%$), fat ($20\%$ to $35\%$), and protein ($10\%$ to $35\%$) expressed as percentages of total daily caloric intake that provide adequate total energy while minimizing chronic disease risk.

Chronic Disease Risk Reduction Intakes (CDRR)

Levels of nutrient intake associated with low risks of chronic disease, such as the threshold above which intake reduction lowers disease risk in healthy populations.

Estimated Energy Requirement (EER)

The average dietary energy intake predicted to maintain energy balance in a healthy adult of a defined age, sex, weight, height, and level of physical activity consistent with good health.

Daily Values (DV)

Nutrient standards based on a $2,000\text{-calorie}$ diet used on food labels and on grocery and restaurant signs to enable general comparisons among foods.

Peristalsis

The wavelike muscular squeezing motions of the esophagus, stomach, and small intestine that push their contents along the digestive tract.

Chyme

The fluid resulting from the grinding, churning, and chemical actions of the stomach upon a swallowed meal.

Bile

A cholesterol-derived digestive fluid produced by the liver, stored in the gallbladder, and secreted into the small intestine that emulsifies fats and oils.

Villi

Fingerlike projections lining the sheets of cells of the intestinal tract that enormously expand its surface area to facilitate nutrient absorption.

Monosaccharides

Single sugar units, which include glucose, fructose, and galactose.

Disaccharides

Pairs of single sugars linked together, which include sucrose (glucose linked to fructose), maltose (two glucose units), and lactose (glucose linked to galactose).

Polysaccharides

Complex carbohydrates composed of long strands of thousands of glucose units linked together, including starch, glycogen, and cellulose.

Glycogen

A highly branched polysaccharide that is manufactured and stored in animal liver and muscle tissues as a reserve form of glucose.

Soluble Fibers

Food components that readily dissolve in water, become viscous, form gels, and are often readily fermented by bacteria in the human colon.

Insoluble Fibers

Tough, fibrous plant structures such as cellulose that do not dissolve in water, do not form gels, and resist fermentation by colonic bacteria.

Ketosis

An undesirably high concentration of acidic ketone bodies in the blood or urine that arises when fat is broken down without sufficient carbohydrate.

Insulin

A hormone secreted by the pancreas in response to elevated blood glucose that facilitates cellular glucose uptake and stimulates glycogen synthesis.

Glucagon

A pancreatic hormone released in response to low blood glucose that stimulates the liver to dismantle stored glycogen and release free glucose into the blood.

Triglycerides

The major class of dietary lipids and primary storage form of fat in the body, consisting of three fatty acids linked to one glycerol molecule.

Saturated Fatty Acid

A fatty acid carbon chain carrying the maximum possible number of hydrogen atoms, containing no points of unsaturation (no double bonds).

Trans-Fatty Acids

Fatty acids with unusual chemical geometries that arise when polyunsaturated oils are partially hardened by industrial hydrogenation.

Low-Density Lipoproteins (LDL)

Lipoproteins that transport cholesterol and other lipids from the liver to peripheral tissues; elevated blood levels are associated with increased risk of cardiovascular disease.

High-Density Lipoproteins (HDL)

Lipoproteins that scavenge excess cholesterol from body tissues and return it to the liver for disposal; higher blood levels correlate with reduced cardiovascular risk.

Essential Fatty Acids

Fatty acids that the body cannot manufacture from other raw materials and must obtain from food, specifically linoleic acid (omega-$6$) and linolenic acid (omega-$3$).

Denaturation

The irreversible alteration in a protein's folded three-dimensional shape brought about by heat, acids, bases, alcohol, or heavy metal salts.

Nitrogen Balance

The amount of nitrogen consumed in dietary protein compared with the amount of nitrogen excreted from the body in a given time period.

Complementary Proteins

Two or more incomplete dietary proteins whose amino acid profiles balance each other so that the essential amino acids missing from one are provided by the other.

Free Radicals

Atoms or molecules with one or more unpaired electrons that make them unstable, reactive, and capable of initiating destructive oxidative chain reactions in cells.

Neural Tube Defects (NTD)

Severe congenital abnormalities of the brain and spinal cord, such as spina bifida and anencephaly, caused by incomplete closure of the embryonic neural tube, often linked to maternal folate deficiency.

Intrinsic Factor

A compound secreted by the stomach that binds to vitamin $B_{12}$ to enable its absorption in the small intestine, preventing pernicious anemia.

Sarcopenia

The age-related progressive loss of skeletal muscle mass, strength, and function, commonly accelerated by physical inactivity.

Severe Acute Malnutrition (SAM)

A life-threatening condition caused by recent, severe food restriction, characterized in children by rapid weight loss and wasting (marasmus) or edema (kwashiorkor).

Sustainable Diet

A dietary pattern that meets nutrient needs and supports human health across all life stages, protects biodiversity and natural ecosystems, is economically fair and affordable, and respects animal welfare.