EHS 150 Lecture Notes - Lecture 4: Megavitamin Therapy, Malnutrition, Provitamin
Document Summary
Most synthesized vitamins work equally well in the body. Scientists believe they have discovered all the vitamins. Vitamins in the digestive tract: 40-90% of the vitamins are absorbed in the small intestine. Bioavailability refers to the amount of a nutrient that can be absorbed and utilized in the body. Provitamin or vitamin precursor: fortified and enriched. Water-soluble vitamins: dissolve in water, generally readily excreted from body, subject to cooking losses, function as coenzymes, participate in energy metabolism, 50-90% of b vitamins are absorbed, marginal deficiency more common, enrichment act. Thiamin in the diet: widely distributed, may be destroyed during cooking, refining and storage. Riboflavin in the diet: milk is the best source in the u. s, destroyed by exposure to light. Riboflavin deficiency and toxicity: deficiency symptoms: ariboflavinosis, skin and other tissue problems, confusion, occurs in conjunction with deficiencies of other b vitamins, toxicity.