Summary BIOD 121 Portage module 4

essential vitamins - 13 vitamins that animal cells need but can't synthesize found in both plant and animal sources vitamins produced by the body - vitamin K and biotin (gut flora) vitamin D (skin) vitamin A (from beta carotene) niacin (tryptophan) two criteria for vitamins - 1. must be consumed in the diet to maintain health. 2. symptoms of deficiency occur in its absence enrichment - adding nutrients back that have been lost to processing fortification - adding nutrient not naturally present in a food Fat soluble vitamins - Vitamins A, D, E, K stored in liver and adipose tissue excess consumption could lead to toxic levels two forms of vitamin a - 1. Preformed Vitamin A (retinol/retinal), found in foods and animal products: liver, fish, fish oils, fortified milk, yogurt, and eggs 2. Provitamin A or Carotene, the pigment in yellow, orange, and deep green fruits or vegetables vitamin A functions - Vision skin and epithelial health growth, development, reproduction disease prevention two forms of vitamin D - D2 (ergocalciferol, synthetic) and D3 (cholecalciferol) produced skin liver kidney fatty fish, fortified cereal, eggs, butter, fortified milk, and yogurt vitamin D functions - regulation of calcium levels and bone metabolism immune system, skin development, muscle health, and blood pressure control vitamin A deficiency - Night blindness, xeropthalmia, dry skin, growth failure toxicity 3000mcg/day increased hip fracture, liver toxicity, and fetal malformations vitamin D deficiency - rickets, osteomalacia increased risk of infections, cancers, autoimmune disease, and cardiovascular disease vitamin E function - antioxidant that protects erythrocytes and membranes from damage in the body (alpha-tocopherol) or in plants (gamma-tocopherol) oils, cereals, eggs, margarines, whole grains, and nuts. vitamin E deficiency - Rare, can occur if fat malabsorption is present cellular breakdown and hemolysis toxicity 1000mg/day may interfere with blood clotting action of Vitamin K vitamin K function - blood clotting, bone formation oils, plants, fish and meats, green leafy vegetables, green beans, soybean and canola oils, and liver synthesize small amts in GI tracts (except infants) 80mcg deficiency and toxicity both rare water soluble vitamins - B vitamins and vitamin C likelihood of toxicity is minimal unless consumed in extremely large quantities (supplements) B vitamins - coenzymes involved in converting the energy in carbohydrate, fat, and protein into ATP thiamin, riboflavin, niacin, pantothenic acid, biotin, vitamin B-6, folate, and vitamin B-12 bioavailability - amount of a vitamin that is absorbed and available to the body thiamin (B1) - coenzyme for carbohydrates, promotes glucose metabolism pork, legumes, milk, orange juice, organ meats, and whole and enriched grain Thiamin deficiency - Beriberi: weakness, loss of appetite, irritability, poor arm and leg coordination, an enlarged heart, and severe edema (where white rice is common) Riboflavin (B2) - coenzyme for energy metabolism that requires oxygen vitamin and mineral metabolism very sensitive to light * enriched grains, meat, eggs, and milk products Riboflavin deficiency - ariboflavinosis (rare) glossitis (inflammation of the tongue), cheilosis (cracks around the mouth), sun sensitivity, and confusion niacin (B3) - nicotinic acid or nicotinamide release of energy from carbohydrates, proteins, and fats make 50% req'd niacin from tryptophan, an amino acid. * Meat, enriched breakfast cereals, poultry, fish, nuts, and peanuts niacin deficiency - pellagra: dermatitis, diarrhea, dementia, death (4Ds) excess niacin: flushing Pantothenic Acid (B5) - component of coenzyme A or CoA important in fatty acid production * chicken, pork, fish, egg yolks, yogurt, legumes, avocados, and sweet potatoes B-6 - 3 chemical forms-pyroxidine key role in protein and amino acid metabolism; enables cells to make nonessential amino acids by removing the nitrogen group important for the synthesis of white and red blood cells and for neurotransmitter synthesis pyroxidine deficiency - microcytic hypochromic anemia: small, oxygen-deficient red blood cells CNS disturbance, seizures Biotin (B7) - aids in the production of glucose and fatty acids, DNA synthesis, and amino acid metabolism * cauliflower, liver, peanuts, cheese, and egg yolks (uncooked whites contain avidin which prevents absorption) Folate (B9) - DNA synthesis and cell division as well as metabolizing amino acids and homocysteine * meats, fish, eggs, and milk Folate deficiency - megaloblastic anemia (large, undivided cells) prenatal neural tube defects, spina bifida 400 mcg/day of folate during childbearing years older adults: depression, mental confusion, poor growth, diarrhea, and altered nerve function upper limit 1000mcg Vitamin B12 - convert the folate coenzyme to the active form needed for DNA synthesis homocysteine metabolism