Folate

Raw green leafy vegetables, fruits, organ meats (eg, liver), enriched cereals and breads

Maturation of red blood cells

Synthesis of purines, pyrimidines, and methionine

Development of fetal nervous system

Deficiency: Megaloblastic anemia, neural tube birth defects, confusion

(nicotinic acid, nicotinamide)

Liver, red meat, fish, poultry, legumes, whole-grain or enriched cereals and breads

Oxidation-reduction reactions

Carbohydrate and cell metabolism

Deficiency: Pellagra (dermatitis, glossitis, gastrointestinal and central nervous system dysfunction)

Toxicity: Flushing

(vitamin B2)

Milk, cheese, liver, meat, eggs, enriched cereal products

Many aspects of carbohydrate and protein metabolism

Integrity of mucous membranes

Deficiency: Cheilosis, angular stomatitis, corneal vascularization

Thiamin (vitamin B1)

Whole grains, meat (especially pork and liver), enriched cereal products, nuts, legumes, potatoes

Carbohydrate, fat, amino acid, glucose, and alcohol metabolism

Central and peripheral nerve cell function

Myocardial function

Deficiency: Beriberi (peripheral neuropathy, heart failure), Wernicke-Korsakoff syndrome

(retinol)

As preformed vitamin: Fish liver oils, liver, egg yolks, butter, vitamin A–fortified dairy products

As provitamin carotenoids: Dark green and yellow vegetables, carrots, yellow and orange fruits

Formation of rhodopsin (a photoreceptor pigment in the retina)

Integrity of epithelia

Lysosome stability

Glycoprotein synthesis

Deficiency: Night blindness, perifollicular hyperkeratosis, xerophthalmia, keratomalacia, increased morbidity and mortality in young children

Toxicity: Headache, peeling of skin, hepatosplenomegaly, bone thickening, intracranial hypertension, papilledema, hypercalcemia

Vitamin B6

Organ meats (eg, liver), whole-grain cereals, fish, legumes

Many aspects of nitrogen metabolism (eg, transaminations, porphyrin and heme synthesis, tryptophan conversion to niacin)

Nucleic acid biosynthesis

Fatty acid, lipid, and amino acid metabolism

Deficiency: Seizures, anemia, neuropathies, seborrheic dermatitis

Toxicity: Peripheral neuropathy

Vitamin B12 (cobalamins)

Meats (especially beef, pork, and organ meats [eg, liver]), poultry, eggs, fortified cereals, milk and milk products, clams, oysters, mackerel, salmon

Maturation of red blood cells, neural function, DNA synthesis, myelin synthesis and repair

Deficiency: Megaloblastic anemia, neurologic deficits (confusion, paresthesias, ataxia)

Vitamin C

Citrus fruits, tomatoes, potatoes, broccoli, strawberries, sweet peppers

Collagen formation

Bone and blood vessel health

Carnitine, hormone, and amino acid formation

Wound healing

Deficiency: Scurvy (hemorrhages, loose teeth, gingivitis, bone defects)

(cholecalciferol, ergocalciferol)

Direct ultraviolet B irradiation of the skin (main source), fortified dairy products (main dietary source), fish liver oils, fatty fish, liver

Calcium and phosphate absorption

Mineralization and repair of bone

Tubular reabsorption of calcium

Insulin and thyroid function, improvement of immune function, reduced risk of autoimmune disease

Deficiency: Rickets (sometimes with tetany), osteomalacia

Toxicity: Hypercalcemia, anorexia, renal failure, metastatic calcifications

group (alpha-tocopherol, other tocopherols)

Vegetable oils, nuts

Intracellular antioxidant

Scavenger of free radicals in biologic membranes

Deficiency: Red blood cell hemolysis, neurologic deficits

Toxicity: Tendency to bleed

Vitamin K group (phylloquinone, menaquinones)

Green leafy vegetables (especially collards, spinach, and salad greens), soy beans, vegetable oils

Bacteria in the gastrointestinal tract after neonatal period

Formation of prothrombin, other coagulation factors, and bone proteins

Deficiency: Bleeding due to deficiency of prothrombin and other factors, osteopenia