Vitamin Source Function Excess Deficiency Vitamin A Retinol = active form Carotenoids = Inactive form Retinol: Fat-containing animal foods such as liver, butter, cream, whole milk, cheeses, egg yolk Carotenoids: Green leafy vegetables & fruits, carrots, sweet potatoes, squash, spinach, broccoli, mango, cantaloupe, pumpkin Antioxidant; protects cells from destruction by oxygen. Maintains healthy eyes and skin and a healthy immune system. Helps prevent infection. Birth defects, hair loss, dry skin, dryness of mucous membranes, liver damage Night blindness; dry, rough skin; increased susceptibility to infections; and blindness or xerophthalmia Vitamin D Sunlight (changes a provitamin to vitamin D3 in humans) Milk, fish, liver oils, egg yolk, butter, fortified margarine Promote calcium and phosphorus absorption in the body and raise their concentration in the blood so that normal bone and tooth mineralization can occur and tetany (involuntary muscle movement) can be prevented. Deposits of calcium and phosphorus in soft tissues, kidney and heart damage Increase the chance for kidney stones. Poor bone and tooth formation, rickets which causes malformed bones and pain in infants Osteomalacia (softening of bones) Osteoporosis (brittle, porous bones) Vitamin E Vegetable oils: corn, soybean, safflower, and cottonseed, and products made from them such as margarine Wheat germ, nuts, green leafy vegetables Antioxidant Prevention of hemolytic anemia among premature infants Enhance immune system Prevent spoilage of commercial foods Relatively nontoxic, fat-soluble vitamin. Excess stored in adipose tissue. Avoid long-term megadoses. Serious neurological defects can occur from malabsorption. Vitamin K Green leafy vegetables: spinach broccoli, cabbage. Dairy products: eggs, meats Fruits, and cereals. Bacteria in small intestine Formation of prothrombin; clotting of blood Vitamin K is given for Newborns immediately after birth Anemia can result from excessive amounts of synthetic vitamin K Defective blood coagulation, which increases clotting time and makes client prone to hemorrhage
synthesizes some vitamin K. Clients who suffer from faulty fat absorption After extensive antibiotic therapy (it kills normal flora) Antidote for an overdose of anticoagulant Clients being treated for hemorrhage Vitamin B1 Thiamin Unrefined and enriched cereals, yeast, wheat germ, organ meats, seeds, nuts, and legumes Essential for nerve and muscle action, and metabolism of carbohydrates and some amino acids. Nervous irritability, and constipation. Beriberi is a disease caused by extreme deficiency of vitamin B1. It affects the nervous, CV, GI systems. Vitamin B2 Riboflavin Sources include milk, meats, poultry, fish, enriched breads, cereals, broccoli, spinach, and asparagus Necessary for: Metabolism of carbohydrates, protein, and fats. Tissue maintenance (especially the skin around the mouth); Healthy eyes. Cheilosis (a condition characterized by sores on the lips and cracks at the corners of the mouth); Glossitis (inflammation of the tongue); Dermatitis Niacin Meats, poultry, fish, peanuts, legumes. Milk and eggs are sources of tryptophan (precursor). A coenzyme in energy metabolism May be used as a agent under close supervision of a physician due to adverse side effects Excessive amounts of niacin may cause flushing due to vascular dilation, GI problems, itching, and liver damage Weakness, indigestion, anxiety, and irritability. Pellagra: is an extreme deficiency causing sores on the skin, diarrhea, anxiety, confusion, irritability, poor memory, dizziness, and untimely death.
Vitamin B6 Pyridoxine Poultry, fish, liver, kidney, potatoes, bananas, spinach, and unrefined whole grains Essential for protein metabolism and absorption, and aids in release of glucose from glycogen. Serves as catalyst in conversion of tryptophan (inactive niacin) to niacin; Helps synthesize neurotransmitters such as serotonin and dopamine. Toxicity is rare Deficiency symptoms include irritability, depression, and dermatitis. Oral contraceptives interfere with metabolism of vitamin B6 and can result in a deficiency. Folic acid (folate) Cereals fortified with folate, green leafy vegetables, legumes, sunflower seeds, fruits such as orange juice and strawberries Needed for DNA synthesis, Protein metabolism, Formation of hemoglobin Increased need during pregnancy and growth. 600 g/day required one month before conception through first six weeks of pregnancy. Excess can mask vitamin B12 deficiency and inactivates phenytoin, an anticonvulsant drug used by epileptics. Deficiency may lead to neural tube defects in fetus such as spina bifida (spinal cord or spinal fluid bulge through the back) and anencephaly (absence of the brain). Other signs include inflammation of mouth and tongue, poor growth, problems with nerve functions. Megaloblastic anemia Vitamin B12 Cobalamin Animal foods, especially organ meats, lean meat, seafood, eggs, dairy products. Increased need during pregnancy and lactation. Involved in folate metabolism, maintenance of the myelin sheath, and healthy red blood cells. To be absorbed, must bind with intrinsic factor in stomach. Pernicious anemia may result from loss of intrinsic factor. Deficiency is rare Symptoms include pernicious anemia (if intrinsic factor absent), sore mouth and tongue, pallor, weight loss, neurological system damage. Pantothenic Acid Sources include meats, poultry, fish, eggs, whole grain cereals, and Involved in metabolism of carbohydrates, fats, proteins. Toxicity from excess not confirmed Natural deficiencies unknown
legumes. Thought to be synthesized by the body Essential for synthesis of neurotransmitter acetylcholine and steroid hormones. Biotin Sources include liver, egg yolk, soy flour, cereals, yeast. Synthesized in intestine by microorganisms. Coenzyme in synthesis of fatty acids and amino acids. Toxicity from excess unknown Deficiency symptoms include, depression, pallor, dermatitis, increase in serum cholesterol. Vitamin C Ascorbic acid Sources include citrus fruits, melon, strawberries, tomatoes, potatoes, red and green peppers, cabbage, broccoli. Stress and cigarette smoking increase need. Has antioxidant properties and protects food from oxidation. Role in formation of collagen (protein substance that holds body cells together). Aids in absorption of iron. May be involved with formation or functioning of norepinephrine, leukocytes, the immune system, allergic reactions Generally considered nontoxic. Diarrhea, cramps, excessive absorption of food iron, rebound scurvy (when megadoses are stopped abruptly) and possibly oxalate kidney stones. Scurvy: disease characterized by gingivitis, easy bruising, pinpoint hemorrhages of the skin, poor wound healing, sore joints and muscles, weight loss. Extreme cases result in death. Deficiency of Vitamin C: bleeding gums, loose teeth, tendency to bruise easily, poor wound healing.