Macronutrients, Fat-Soluble, and Water-Soluble Vitamins Flashcards

Vocabulary practice flashcards covering macronutrient principles, fat-soluble vitamins, and water-soluble vitamins based on lecture material.

Estimated Average Requirement (EAR)

The average daily intake level estimated to meet the nutrient requirements of $50\%$ of healthy individuals in a given life stage and gender group.

Recommended Dietary Allowance (RDA)

The average daily level of intake sufficient to meet the nutrient requirements of nearly all ($97\text{--}98\%$) healthy individuals.

Adequate Intake (AI)

An intake level assumed to ensure nutritional adequacy, established when scientific evidence is insufficient to set an EAR or RDA.

Tolerable Upper Intake Level (UL)

The maximum daily intake level of a nutrient that is unlikely to cause adverse health effects in the general population.

Total Energy Expenditure (TEE)

The total amount of energy spent by an individual over a 24-hour period, consisting of resting metabolic rate ($\sim 60\%$), physical activity ($\sim 30\%$), and the thermic effect of food ($\sim 10\%$).

Resting Metabolic Rate (RMR)

The energy expended by an individual in a resting, post-absorptive state for normal bodily functions such as respiration, blood flow, and ion transport.

Thermic Effect of Food (TEF)

The metabolic energy expended for the digestion, absorption, and transport of ingested nutrients, accounting for approximately $10\text{--}15\%$ of Total Energy Expenditure.

Glycemic Index (GI)

A measure representing how fast blood glucose levels increase after consumption of carbohydrate-containing foods compared to pure glucose.

Glycemic Load (GL)

A value combining the Glycemic Index of a food with its available carbohydrate content per serving, calculated as $\text{GL} = \frac{\text{GI}_{\text{food}} \times \text{g of carbs per serving}}{100}$.

Nitrogen Balance

The net difference between dietary nitrogen intake and nitrogen excretion relative to the body's amino acid pool.

Kwashiorkor

A form of severe protein-energy undernutrition caused by low protein intake despite adequate caloric intake, characterized by abdominal edema, hair loss, skin rash, fatty liver, and lethargy.

Marasmus

A severe form of protein-energy undernutrition caused by deficiency in both calories and protein, presenting with extreme muscle wasting, prominent bones, and an 'old man' appearance.

Linolenic Acid (ALA)

An essential omega-3 fatty acid ($18:3\omega\text{-}3$) found in plant oils that acts as an indispensable precursor to regulatory eicosanoids.

Linoleic Acid (LA)

An essential omega-6 fatty acid ($18:2\omega\text{-}6$) required in the diet to maintain cell membrane integrity, skin barrier function, and eicosanoid synthesis.

Trans-unsaturated Fatty Acids

Unsaturated fatty acids produced industrially by hydrogenation that raise LDL cholesterol, lower HDL cholesterol, and increase cardiovascular disease risk.

Retinol

The preformed active form of vitamin A present in animal sources and supplements, stored as retinyl esters in the liver and adipose tissue.

Retinal

The oxidized derivative of retinol that binds to opsin to form rhodopsin, essential for photoreception in vision.

Retinoic Acid

The oxidized form of retinal that binds nuclear receptors to regulate gene transcription, controlling epithelial cell differentiation and keratin synthesis.

Calcitriol

The active hormonal form of vitamin D ($1,25\text{-diOH-}D_3$) formed by sequential hydroxylations in the liver and kidney to maintain plasma calcium concentration.

Rickets

A vitamin D deficiency disorder in children where incomplete mineralization of the bone collagen matrix leads to soft, pliable, and bowed bones.

Osteomalacia

A condition in adults caused by vitamin D deficiency, resulting in the demineralization of existing bone tissue and increased fracture risk.

alpha-Tocopherol

The most active and biologically abundant form of vitamin E ($\alpha\text{-tocopherol}$) in the human body, acting as a lipid-soluble antioxidant that scavenges free radicals.

gamma-Carboxyglutamate (Gla) Residues

Carboxylated glutamyl residues on blood-clotting factors (II, VII, IX, X) synthesized by $\gamma\text{-glutamyl carboxylase}$ using vitamin K as a coenzyme.

Warfarin

A synthetic vitamin K analogue anticoagulant that inhibits vitamin K epoxide reductase (VKOR), blocking the regeneration of active vitamin K hydroquinone.

Thiamine Pyrophosphate (TPP)

The active coenzyme form of vitamin $B_1$ required for transketolase carbon shuffling and oxidative decarboxylation of $\alpha\text{-keto}$ acids.

Beriberi

A thiamine (vitamin $B_1$) deficiency disease presenting as dry beriberi (peripheral neuropathy and confusion) or wet beriberi (edema, heart failure, and cardiovascular impairment).

Wernicke-Korsakoff Syndrome

A severe thiamine deficiency state primarily linked to alcoholism, characterized by nystagmus, ophthalmoplegia, memory loss, ataxia, and confusion.

Angular Cheilitis

Inflammation and fissuring at the corners of the mouth associated with riboflavin (vitamin $B_2$) deficiency.

Pellagra

A disease caused by severe niacin (vitamin $B_3$) deficiency, defined by the classic symptom sequence of diarrhea, dermatitis, dementia, and death.

Pyridoxal Phosphate (PLP)

The active coenzyme form of vitamin $B_6$ involved in amino acid transamination, decarboxylation, glycogen breakdown, and neurotransmitter synthesis.

Tetrahydrofolate (THF)

The active reduced coenzyme form of vitamin $B_9$ produced via dihydrofolate reductase that acts as a donor in one-carbon unit transfers for nucleotide synthesis.

Methotrexate

A folic acid analogue and competitive inhibitor of dihydrofolate reductase (DHFR) used to treat psoriasis, rheumatoid arthritis, and neoplastic diseases.

Intrinsic Factor (IF)

A gastric protein required for the intestinal absorption of vitamin $B_{12}$, the deficiency of which leads to pernicious anemia.

Scurvy

A disease caused by vitamin C deficiency, presenting with sore spongy gums, loose teeth, fragile blood vessels, and joint swelling due to impaired collagen hydroxylation.