Comprehensive Study Notes: Vitamins, Minerals, and Water Balance

General Characteristics of Vitamins

Definition and Properties

• Vitamins are tasteless, organic compounds required in small amounts for normal body functioning.

• They are classified as either fat-soluble (A, D, E, K) or water-soluble (B vitamins, C).

• Vitamins differ in bioavailability, which is the proportion absorbed and utilized by the body.

Fat-Soluble vs. Water-Soluble Vitamins

Absorption and Storage

• Fat-soluble vitamins (A, D, E, K): Absorbed with dietary fat, stored in the body (mainly liver and fat tissue).

• Water-soluble vitamins (B vitamins, C): Absorbed with water, not stored in large amounts, excess excreted in urine.

Vitamin A

Functions

• Essential for healthy eyes and cell differentiation.

• Supports immunity by promoting gene expression for healthy skin, mucous membranes, bone growth, fetal development, and white blood cell function.

Deficiency

• Leads to xerophthalmia (permanent corneal damage), stunted growth, and night blindness.

• Major cause of preventable blindness in children globally.

Sources

• Retinoids (animal foods), carotenoids (plant foods).

Vitamin D

Functions

• Regulates calcium and phosphorus absorption, maintaining healthy bones and teeth.

• Stimulates intestinal absorption of calcium and phosphorus.

Deficiency

• Causes rickets in children (soft, weak bones) and osteomalacia in adults.

Vitamin E

Functions

• Acts as a powerful antioxidant, protecting cell membranes and preventing oxidation of LDL cholesterol.

• Functions as an anticoagulant, inhibiting blood clot formation.

Vitamin K

Functions

• Essential for blood clotting and bone health.

B Vitamins

General Role

• Function as coenzymes in energy metabolism, aiding many enzymes in chemical reactions.

Key Deficiencies

• Thiamin (B1): Deficiency causes beriberi (affects cardiovascular and nervous systems).

• Riboflavin (B2): Deficiency leads to sore throat, mouth inflammation, and skin issues.

• Niacin (B3): Deficiency causes pellagra (dermatitis, diarrhea, dementia, death).

• Vitamin B6: Deficiency can cause nerve problems and muscle weakness.

• Folate: Deficiency can cause macrocytic anemia and, during pregnancy, neural tube defects (e.g., spina bifida).

• Vitamin B12: Deficiency leads to macrocytic anemia and nerve damage; requires intrinsic factor for absorption.

Vitamin C

Functions

• Acts as an antioxidant.

• Helps synthesize collagen and certain amino acids.

• Enhances iron absorption from plant foods.

Deficiency

• Leads to scurvy (bleeding gums, weakened immunity).

Antioxidants

Role and Mechanism

• Antioxidants (vitamins A, C, E, and beta-carotene) neutralize free radicals, reducing cell damage and risk of chronic diseases.

• Free radicals are unstable molecules that can damage cells and DNA.

Water and Fluid Balance

Functions of Water

• Solvent and transport medium for nutrients and waste.

• Medium for chemical reactions.

• Helps maintain body temperature and lubricates joints, eyes, and mucous membranes.

• Protects organs and fetus.

Fluid Needs

• Depend on physical activity, environment, and diet.

Electrolyte Balance

• Electrolytes (minerals like sodium, potassium) help maintain fluid balance.

Minerals

General Characteristics

• Inorganic elements needed in small amounts.

• Bioavailability varies; some minerals compete for absorption.

Major Minerals

• Calcium: Builds bones/teeth, muscle and nerve function, blood pressure regulation.

• Phosphorus: Bone/teeth structure, cell membranes, DNA/RNA.

• Sodium: Fluid balance, nerve transmission, muscle contraction.

• Potassium: Fluid balance, muscle/nerve function, may lower blood pressure.

Trace Minerals

• Iron: Oxygen transport (hemoglobin/myoglobin), energy metabolism.

• Iodine: Thyroid hormone synthesis; deficiency causes goiter and cretinism.

Iron Forms and Absorption

• Heme iron: Animal sources, easily absorbed.

• Nonheme iron: Plant sources, less easily absorbed due to phytates and other inhibitors.

• Absorption increases if body stores are low.

Dietary Sources and Recommendations

Sodium

• 75% from processed foods; 10% naturally in foods; 5-10% added during cooking/eating.

Potassium

• Fruits and vegetables are major sources; recommended intake is 4,700 mg/day for adults.

Folate

• Sources: Dark green vegetables, enriched grains, legumes, orange juice.

Fluid Content of Foods

Food Group	Examples	Water Content (%)
Vegetables (cooked)	Potatoes	>70%
Vegetables (raw)	Lettuce, tomatoes	>90%
Fruits	Peaches, pears, oranges, grapes, apples	80-90%
Fruits	Watermelon	>90%
Grains	Baked goods
Grains	Pasta, rice (cooked)
Meat	Beef, chicken
Eggs	Eggs	70-79%
Fish	Fish	70-79%
Dairy	Frozen yogurt	70-79%
Dairy	Milk	80-89%

Special Topics

Folate and Pregnancy

• Folate deficiency during pregnancy can cause neural tube defects (e.g., spina bifida).

Vitamin Interactions

• Folate and vitamin B12 are both essential for DNA synthesis and red blood cell formation.

• Deficiency in one can mask or worsen deficiency in the other.

Vitamin B12 Absorption

• Requires intrinsic factor (protein made in the stomach) for absorption.

• Deficiency common in people who cannot make intrinsic factor (e.g., older adults).

Vitamin C and the Common Cold

• Research shows vitamin C is not effective in preventing the common cold, but may reduce severity in some people.

• Other remedies (e.g., zinc, echinacea) have mixed evidence.

Bottled vs. Tap Water

• Tap water is regulated and generally safe; bottled water is not always purer than tap water.

• Fluoridation of tap water helps prevent dental caries.

USP Seal on Supplements

• The USP seal indicates approval of supplement quality and safety, but not efficacy of health claims.

Additional info:

• Some context and explanations have been expanded for clarity and completeness.

• Tables and lists have been reconstructed for study purposes.