Nutrition, Food Choices, and Human Health Flashcards

Comprehensive vocabulary flashcards reviewing key definitions, nutrient classes, dietary standards, digestive anatomy, and carbohydrate biochemistry from Chapters 1 through 4.

Hunger

The physiological drive to find and eat food, regulated primarily by internal biological mechanisms.

Appetite

The psychological drive to eat, triggered by external food cues, flavor preferences, and social factors.

Satiety

A state of feeling full in which there is no longer a desire or drive to eat.

Nutrition

The science that links foods to health and disease, including the processes of ingestion, digestion, absorption, transport, and excretion of food substances.

Essential Nutrient

A substance that has an omitted biological function, causes a decline in health when omitted, and restores normal function when replenished.

Kilocalorie (kcal)

The amount of heat required to raise the temperature of $1\,g$ of water by $1\,^\circ\text{C}$, used as the standard unit of energy in nutrition.

Phytochemicals

Health-promoting non-nutrient chemical components found in plant foods, such as carotenoids, flavonoids, and resveratrol.

Energy Density

A measurement comparing the energy content ($kcal$) of a food with the weight or volume of its serving.

Nutrient Density

A measurement comparing the nutrient content of a food with the total amount of calories it provides.

Anthropometric Assessment

Measurement of body dimensions and composition, including weight, height, circumferences, and skinfold thickness.

Biochemical Assessment

Laboratory assessment of nutritional status through measurements of nutrients or nutrient by-products in blood, urine, or feces.

Clinical Assessment

Physical examination of body structures (such as skin, eyes, tongue, and hair) to detect physical signs of nutritional deficiencies or disease.

Dietary Assessment

Estimation of typical food intake and choices using instruments like 24-hour recalls, diet records, or food frequency questionnaires.

Environmental Assessment

Evaluation of a person's living conditions, education level, financial budget, and food access capabilities.

Recommended Dietary Allowance (RDA)

Daily intake amount of a nutrient that meets the needs of $98\%$ of healthy individuals in a specific life stage and sex.

Adequate Intake (AI)

Nutrient intake recommendation set when insufficient research exists to establish a definitive RDA.

Estimated Energy Requirement (EER)

Estimate of daily energy ($kcal$) intake needed to maintain energy balance for an average person of a specific age, sex, height, weight, and activity level.

Tolerable Upper Intake Level (UL)

Maximum chronic daily intake of a nutrient unlikely to cause adverse health effects in almost all healthy individuals.

Daily Value (DV)

Generic nutrient standards on food labels based on a $2000\,kcal$ diet, used to compare nutrient content to approximate daily needs.

Nutrient Content Claim

An FDA-regulated statement on food packaging describing the specific level of a nutrient in a product.

Health Claim

An FDA-regulated claim describing a relationship between a food component and a reduced risk of a disease or health condition.

Structure/Function Claim

A statement describing the role of a nutrient in maintaining normal body structure or function, not pre-approved or evaluated by the FDA.

Lysosomes

Cellular organelles containing digestive enzymes that break down worn-out cell parts and foreign materials.

Peroxisomes

Organelles containing catalase and detoxifying enzymes that break down harmful chemicals and hydrogen peroxide.

Cell Metabolism

The complete set of biochemical reactions occurring within cells to sustain life, including anabolic and catabolic processes.

Adenosine Triphosphate (ATP)

The main form of chemical energy stored and utilized by living cells.

Leptin

A hormone produced by adipose tissue that acts on the hypothalamus to decrease food intake.

Ghrelin

A hormone secreted by stomach cells that acts on the hypothalamus to stimulate hunger, promote fat storage, and release growth hormone.

Cholecystokinin (CCK)

A gastrointestinal hormone that slows GI motility and triggers the release of bile and pancreatic digestive enzymes.

Insulin

A hormone released by the pancreas that lowers blood glucose levels by promoting glucose uptake and storage in tissue cells.

Glucagon

A pancreatic hormone that raises blood glucose levels by promoting liver glycogen breakdown and gluconeogenesis.

Peristalsis

Coordinated, wave-like muscular contractions that move food and chyme through the gastrointestinal tract.

Epiglottis

A flap of tissue that covers the entrance of the larynx and trachea during swallowing to prevent food from entering the airway.

Lower Esophageal Sphincter (LES)

A muscular ring at the junction of the esophagus and stomach that prevents reflux of stomach contents into the esophagus.

Chyme

A fluid mixture of partially digested food and digestive secretions produced in the stomach.

Duodenum

The first $10\,\text{inches}$ of the small intestine, where chyme mixes with bile and pancreatic juice for primary chemical digestion.

Jejunum

The middle segment of the small intestine (~$4\,\text{feet}$ long), where significant nutrient absorption occurs.

Ileum

The terminal section of the small intestine (~$5\,\text{feet}$ long), specialized for absorbing vitamin B-12 and bile salts.

Enterocytes

Intestinal absorptive cells lining the villi of the small intestine that perform nutrient absorption.

Prebiotics

Indigestible carbohydrate fibers that stimulate the growth and activity of beneficial intestinal bacteria.

Probiotics

Live, beneficial microorganisms residing in the large intestine that contribute to gastrointestinal health.

Glucose

A six-carbon monosaccharide that serves as the primary fuel source for red blood cells and the central nervous system.

Fructose

A monosaccharide found in fruits, honey, and high-fructose corn syrup that is converted to glucose in the liver.

Galactose

A monosaccharide that binds with glucose to form lactose and is converted to glucose in the liver.

Sucrose

A disaccharide composed of one glucose molecule and one fructose molecule, commonly known as table sugar.

Lactose

A disaccharide composed of glucose and galactose, naturally present in milk and dairy products.

Maltose

A disaccharide composed of two glucose molecules, produced during the enzymatic breakdown of starch.

Amylose

A straight-chain digestible plant starch composed of glucose units (~$20\%$ of digestible starch in plant foods).

Amylopectin

A highly branched digestible plant starch made of glucose units (~$80\%$ of digestible starch in foods).

Glycogen

The highly branched storage form of glucose stored in animal and human liver (~$400\,kcal$) and muscle tissue (~$1200\,kcal$).

Soluble Fiber

Viscous fibers that dissolve or swell in water, delay gastric emptying, slow glucose absorption, and help reduce blood cholesterol.

Insoluble Fiber

Non-fermentable fibers that do not dissolve in water, acting to increase fecal bulk and decrease intestinal transit time.

Dietary Fiber

Nondigestible carbohydrates and lignin that occur naturally and remain intact in plant foods.

Functional Fiber

Isolated nondigestible carbohydrates added to food products due to their demonstrated health benefits in humans.

Whole Grain

Grain products containing all three structural parts of the seed kernel: bran, endosperm, and germ.

Refined Grain

Grains that have been stripped of the bran and germ, leaving only the starchy endosperm.

Quinoa

A gluten-free pseudo-grain that provides a complete protein source containing all essential amino acids.

High-Fructose Corn Syrup (HFCS)

A corn-derived sweetener manufactured by enzymatically converting glucose into $55\%$ fructose.

Sugar Alcohols

Nutritive sweeteners (e.g., sorbitol, xylitol) providing ~$2.6\,kcal/g$ that are absorbed slowly and do not cause tooth decay.

Acceptable Daily Intake (ADI)

Safety limit for alternative sweeteners, set at $100$ times less than the maximum level found to cause no harm in animal studies.

Lactase

An intestinal brush border enzyme that digests lactose into glucose and galactose.

Sucrase

An intestinal enzyme that digests sucrose into glucose and fructose.

Maltase

An intestinal enzyme that breaks down maltose into two glucose molecules.

Gluconeogenesis

The metabolic pathway that synthesizes new glucose from non-carbohydrate sources like amino acids.

Ketone Bodies

Partial breakdown products of fat oxidation formed when dietary carbohydrate intake is inadequate.

Hyperglycemia

Abnormally high blood glucose concentration, defined as fasting blood glucose greater than $125\,mg/dL$.

Hypoglycemia

Abnormally low blood glucose concentration, defined as blood glucose below $40\text{--}50\,mg/dL$ in non-diabetics.

Prediabetes

A health condition marked by fasting blood glucose of $100\text{--}125\,mg/dL$ or an HbA1c of $5.7\text{--}6.4\%$.

Type 1 Diabetes

An autoimmune disorder in which the immune system destroys pancreatic beta cells, stopping insulin production.

Type 2 Diabetes

A metabolic disease characterized by insulin resistance in target body cells and relative insulin deficiency.

Hemoglobin A1c (HbA1c)

A clinical blood test measuring the percentage of glucose-bound hemoglobin to assess long-term blood glucose control over 2 to 3 months.