VITAMINS


WATER-SOLUBLE VITAMINS

Thiamin (B1)

  • Function: Part of TPP; coenzyme for carbohydrate metabolism and amino acid metabolism; may help produce neurotransmitters

  • RDA: 1.1–1.2 mg

  • Sources: Pork, wheat germ, enriched breads/cereals, legumes, nuts

  • Deficiency: Beriberi, Korsakoff syndrome; weakness, abnormal nervous system functioning

  • Toxicity: None (UL not determined)

Riboflavin (B2)

  • Function: Part of FMN and FAD; coenzymes for carbohydrate, amino acid, and lipid metabolism

  • RDA: 1.1–1.3 mg

  • Sources: Cow’s milk, yogurt, dairy products, enriched breads/cereals

  • Deficiency: Inflammation of mouth and tongue, eye disorders

  • Toxicity: None (UL not determined)

Niacin (B3)

  • Function: Part of NAD and NADP; coenzymes needed for energy metabolism

  • RDA: 14–16 mg

  • Sources: Enriched breads/cereals, beef, liver, tuna, salmon, poultry, pork, mushrooms

  • Deficiency: Pellagra

    • Diarrhea

    • Dermatitis

    • Dementia

    • Death

  • Toxicity: UL = 35 mg/day; flushing of face/skin, dry skin, nausea, liver damage

Pantothenic Acid (B5)

  • Function: Part of coenzyme A needed for synthesizing fat and releasing energy from carbohydrates, fats, and protein

  • RDA: 5 mg

  • Sources: Beef and chicken liver, sunflower seeds, mushrooms, yogurt, fortified cereals

  • Deficiency: Rarely occurs

  • Toxicity: Unknown (UL not determined)

Biotin (B7)

  • Function: Coenzyme needed for synthesizing glucose and fatty acids

  • RDA: 30 µg

  • Sources: Eggs, peanuts, salmon, pork, liver, mushrooms, sunflower seeds

  • Deficiency: Rarely occurs; skin rash, hair loss, convulsions, neurological disorders, developmental delays in infants

  • Toxicity: Unknown (UL not determined)

Vitamin B6 (Pyridoxine)

  • Function: Part of PLP; coenzyme needed for amino acid metabolism; involved in neurotransmitter synthesis and hemoglobin synthesis

  • RDA: 1.3–1.7 mg

  • Sources: Meat, fish, poultry, potatoes, bananas, spinach, sweet red peppers, broccoli

  • Deficiency: Dermatitis, anemia, depression, confusion, neurological disorders such as convulsions

  • Toxicity: UL = 100 mg/day; nerve destruction

Folate (B9)

  • Function: Part of THFA; coenzyme needed for DNA synthesis and conversion of cysteine to methionine; prevents homocysteine accumulation

  • RDA: 400 µg

  • Sources: Dark green leafy vegetables, papayas, asparagus, broccoli, orange juice, enriched breads/cereals (folic acid)

  • Deficiency: Megaloblastic anemia, diarrhea, neural tube defects in embryos

  • Toxicity: UL = 1000 µg/day; may stimulate cancer cell growth

Vitamin B12 (Cobalamin)

  • Function: Part of coenzymes needed for cellular processes, including folate metabolism; maintenance of myelin sheaths

  • RDA: 2.4 µg

  • Sources: Animal foods; fortified cereals; fortified almond, soy, or rice milks

  • Deficiency: Pernicious anemia, megaloblastic anemia, nerve damage resulting in paralysis and death

  • Toxicity: None (UL not determined)

Vitamin C (Ascorbic Acid)

  • Function: Substance needed for connective tissue synthesis and maintenance; antioxidant; synthesis of neurotransmitters and certain hormones; immune system functioning

  • RDA: 75–90 mg (higher for smokers)

  • Sources: Peppers, citrus fruits, cherries, broccoli, cabbage, berries

  • Deficiency: Scurvy; poor wound healing, pinpoint hemorrhages, bleeding gums, bruises, depression

  • Toxicity: UL = 2000 mg/day; diarrhea and GI tract discomfort

FAT-SOLUBLE VITAMINS

Vitamin A (Preformed and Provitamin A)

  • Function: Normal vision and reproduction; cellular growth; immune system function

  • RDA: 700–900 µg RAE

  • Sources:

    • Preformed: liver, cow’s milk, fortified cereals

    • Provitamin: yellow-orange and dark green fruits/vegetables

  • Deficiency: Night blindness, xerophthalmia, poor growth, dry skin, reduced immune function

  • Toxicity: UL = 3000 µg/day; nausea, vomiting, headaches, bone pain/fractures, hair loss, liver damage, interference with vitamin K absorption

Vitamin D

  • Function: Absorption of calcium and phosphorus; maintenance of normal blood calcium; bone calcification; immune function

  • RDA: 15–20 µg

  • Sources: Fortified cow’s milk, fortified cereals, fish liver oils, fatty fish

  • Deficiency: Rickets (children), osteomalacia (adults); soft bones, depressed growth, reduced immune function

  • Toxicity: UL = 100 µg/day; poor growth, calcium deposits in soft tissues

Vitamin E

  • Function: Antioxidant

  • RDA: 15 mg (alpha-tocopherol)

  • Sources: Vegetable oils, products made from these oils, certain fruits/vegetables, nuts, seeds, fortified cereals

  • Deficiency: Loss of muscular coordination, retinal damage, hemolysis of red blood cells (anemia in premature infants)

  • Toxicity: UL = 1000 mg/day; excessive bleeding due to interference with vitamin K metabolism

Vitamin K

  • Function: Production of active blood-clotting factors; prevention of soft tissue calcification

  • RDA: 90–120 µg

  • Sources: Green leafy vegetables, canola and soybean oils, products made from these oils

  • Deficiency: Excessive bleeding

  • Toxicity: UL = undetermined