Nutrition: Concepts and Controversies - Exam Review

Comprehensive vocabulary flashcards covering the chapters on Vitamins (Ch. 7), Performance Nutrition (Ch. 10), Proteins and Amino Acids (Ch. 6), Water and Minerals (Ch. 8), and Energy Balance and Body Weight (Ch. 9) from Nutrition: Concepts & Controversies (17th Edition).

Vitamin

An essential, noncaloric, organic nutrient needed in small amounts in the diet to support proper metabolism and bodily functioning, which cannot be synthesized in sufficient quantities by the body.

Precursor (Provitamin)

A compound in food that can be converted into an active vitamin inside the body, such as beta-carotene transforming into vitamin A.

Fat-Soluble Vitamins

A class of vitamins (A, D, E, and K) that dissolve in fats and oils, require bile for absorption, are stored in the liver and adipose tissues, and present a higher risk of toxicity from supplementation.

Water-Soluble Vitamins

A class of vitamins including vitamin C and the B vitamins that dissolve in water, are easily absorbed into the bloodstream, are excreted in urine, and must be consumed frequently because they are not stored extensively.

Beta-Carotene

An orange, plant-derived pigment and antioxidant that functions as a safe, nontoxic precursor to vitamin A, supporting eye health and preventing cellular oxidative damage.

Xerophthalmia

Progressive hardening of the cornea and drying of the eye caused by severe vitamin A deficiency, which can progress to irreversible blindness.

Rickets

The vitamin D-deficiency disease in children characterized by poor bone mineralization, resulting in abnormal bone softening, bowed legs, and beaded ribs.

Osteomalacia

The adult form of vitamin D deficiency characterized by poor bone mineralization and softening of the bones, causing joint pain and increased fracture risk.

Free Radicals

Unstable, highly reactive metabolic by-products that damage cell membranes and tissues through oxidation, which antioxidants like vitamin E neutralize.

Scurvy

The clinical deficiency disease caused by a lack of vitamin C, characterized by breakdown of collagen, bleeding gums, pinpoint hemorrhages, loose teeth, bone fragility, and poor wound healing.

Coenzyme

A small organic molecule, frequently containing a B vitamin, that attaches to an active site on an enzyme to activate it and facilitate chemical reactions.

Beriberi

The deficiency disease associated with a lack of thiamin, characterized by severe muscle weakness, nerve damage, and impaired energy metabolism.

Wernicke-Korsakoff Syndrome

A severe neurological disorder caused by thiamin deficiency, frequently diagnosed in people with chronic alcohol use disorder.

Pellagra

The deficiency disease caused by a lack of dietary niacin, recognized by the '4 Ds': dermatitis, diarrhea, dementia, and death.

Macrocytic Anemia

A blood disorder characterized by the presence of abnormally large, immature red blood cells, caused by a deficiency of folate or vitamin $B_{12}$.

Pernicious Anemia

A severe vitamin $B_{12}$-deficiency disease caused by the inability to absorb the vitamin, which results in anemia, fatigue, and irreversible nerve damage.

Amino Acid

The fundamental building block of proteins containing nitrogen, composed of a central carbon, an amine group, an acid group, and a distinct side chain that determines its chemical properties.

Essential Amino Acids

The nine amino acids that the human body cannot synthesize in sufficient quantities and that must be supplied directly by the diet.

Conditionally Essential Amino Acid

A nonessential amino acid that becomes essential in the diet under conditions of illness or metabolic limitations, such as tyrosine becoming essential when phenylalanine is insufficient in PKU.

Peptide Bond

The covalent chemical bond formed between the amine group of one amino acid and the acid group of another, linking them together into protein strands.

Sickle-Cell Disease

A genetic condition in which valine replaces glutamic acid at the sixth amino acid position in hemoglobin, causing red blood cells to change shape into sickles and lose oxygen-carrying function.

Denaturation

The irreversible unfolding and loss of a protein's three-dimensional structure and function caused by heat, acid, bases, alcohol, radiation, or heavy metal salts.

Protein Turnover

The continuous breakdown and resynthesis of body proteins that requires a constant supply of amino acids to maintain tissues and replace damaged cells.

Edema

The accumulation of excess fluid in interstitial tissue spaces that occurs when the body lacks sufficient protein to maintain fluid balance across cell membranes.

Nitrogen Balance

The quantitative comparison between the amount of nitrogen consumed in dietary protein and the amount excreted by the body in urine, feces, and sweat.

Complementary Proteins

Two or more incomplete protein sources that when eaten together supply adequate amounts of all essential amino acids (e.g., legumes rich in isoleucine and lysine paired with grains rich in methionine and tryptophan).

Water Balance

The physiological balance maintained when water intake (from liquids, foods, and metabolism) equals water output (via the kidneys, skin, lungs, and feces).

Hyponatremia

A dangerously low blood sodium concentration caused by excessive water intake or extreme loss of sodium from prolonged heavy sweating, vomiting, or diarrhea.

Electrolytes

Mineral salts that dissociate into positively and negatively charged ions ($Na^+$, $Cl^-$, $K^+$) in bodily fluids, conducting electrical currents and governing water flow across cell membranes.

Major Minerals

Essential mineral nutrients required in the diet in amounts greater than $100\,\text{mg/day}$, including calcium, phosphorus, magnesium, sodium, potassium, chloride, and sulfate.

Trace Minerals

Essential mineral nutrients required in amounts less than $100\,\text{mg/day}$, such as iron, zinc, iodine, selenium, fluoride, chromium, and copper, all of which are toxic in excess.

Osteoporosis

A reduction in bone mass and structural density where bones become porous and fragile, associated with chronic inadequate calcium intake and aging.

Goiter

An enlargement of the thyroid gland visible in the neck, caused by an iodine deficiency that limits the production of the hormone thyroxine.

Hepcidin

A liver-produced hormone that regulates iron status by controlling intestinal iron absorption and regulating the release of iron from bodily stores.

Pica

A craving for and consumption of nonfood substances, such as clay, chalk, soil, or ice, that is frequently associated with iron deficiency.

Fluorosis

Discoloration, mottling, and pitting of tooth enamel caused by excessive fluoride intake during tooth development in childhood.

Adipokines

Hormones secreted by adipose tissue that travel through the blood to communicate with the brain, liver, and muscle to regulate inflammation, appetite, and insulin sensitivity.

Visceral Fat

Fat stored deep within the abdominal cavity around intra-abdominal organs; strongly linked to chronic inflammation, insulin resistance, and central obesity.

Basal Metabolic Rate (BMR)

The rate at which the body expends energy to support essential, involuntary life-sustaining activities at rest, accounting for $50\text{--}65\%$ of daily energy output.

Components of Energy Expenditure

The three biological divisions of total daily energy output: basal metabolism ($50\text{--}65\%$), physical activity ($25\text{--}50\%$), and the thermic effect of food ($5\text{--}10\%$).

Estimated Energy Requirement (EER)

The predicted average daily dietary energy intake calculated to maintain energy balance in a healthy person based on age, sex, weight, height, and physical activity level.

Ghrelin

A physiological hormone produced in the stomach that stimulates appetite, promotes food intake, and signals hunger to the brain.

Leptin

An appetite-suppressing adipokine produced by fat cells that signals the brain about body fat stores and promotes satiety after eating.

Ketosis

An adaptive physiological state occurring during prolonged carbohydrate deficit or starvation where the liver converts fat breakdown products into ketone bodies to supply energy and spare lean tissue.

Orthorexia

An unhealthy obsession or preoccupation with eating strictly 'clean' or 'pure' foods, which causes psychological distress and functional impairment but is not an official DSM-5 diagnosis.

Muscle Hypertrophy

An increase in muscle mass and cross-sectional size that occurs when muscle protein synthesis exceeds protein breakdown as an adaptation to exercise overload.

Muscle Atrophy

A reduction in muscle size, strength, and tone that occurs as a consequence of muscle disuse, sedentary behavior, or injury.

Excess Postexercise Oxygen Consumption (EPOC)

The elevated rate of oxygen consumption and calorie expenditure that persists after physical activity to restore the body to its resting state.

Relative Energy Deficiency in Sport (RED-S)

A clinical syndrome of impaired physiological function, hormonal disturbance, and poor bone health caused by an athlete consuming insufficient dietary energy relative to exercise expenditure.

Energy Reservoir

A muscle energy system that uses high-energy compounds to instantly trap, store, and release energy for high-intensity bursts lasting $1\text{--}10\,\text{seconds}$, such as sprints or jumps.

Anaerobic Fuel System

A metabolic pathway that breaks down glucose without oxygen, generating quick energy and producing lactate as a by-product to fuel high-intensity, short-duration work.

Aerobic Fuel System

The most efficient metabolic energy system, which requires oxygen to completely oxidize glucose, fatty acids, and amino acids to support sustained, steady-state physical activity.

Sports Anemia

A harmless, temporary training adaptation in which blood fluid volume expands in response to exercise, diluting the concentration of red blood cells without reflecting true iron deficiency.

Ergogenic Aids

Substances, devices, or dietary practices promoted to enhance athletic performance, energy use, or recovery beyond the effects of normal training.

The 4 R's of Recovery

A comprehensive postexercise nutritional recovery framework consisting of refuel glycogen with carbohydrates, repair muscle with protein, replenish micronutrients with whole foods, and rehydrate with fluids and electrolytes within two hours of exercise.