HN 132 Lecture 18 Outline of Last LectureI. Vitamin EII. Vitamin KIII. Vitamin D Outline of Current LectureI. Water-Soluble Vitamins II. Thiamin (B1)III. Riboflavin (B2)IV. Niacin (B3)V. FolateVI. Vitamin (B12)VII. Vitamin CVIII. Pantothenic Acid and BiotinCurrent LectureI. Vitamins that are Water-Soluble A. Water-soluble vitamins are not stored in body1. Excess is excreted in urine2. However, routine intakes of excessive amounts can be harmful.B. B vitamins share common role as coenzymes1. Help many enzymes produce chemical reactions in cellsa. Bind enzymes to promote their activityb. Carriers of electrons, atoms, or chemical groups that participate in the reactionsII. Thiamin (B1) These notes represent a detailed interpretation of the professor’s lecture. GradeBuddy is best used as a supplement to your own notes, not as a substitute.A. First vitamin discoveredB. Functions: 1. Transmission of nerve impulses2. Metabolism of carbohydrates and certain amino acids3. Plays role in breakdown of alcohol in bodyC. Daily needs1. men: 1.2 mg/day; women: 1.1 mg/day D. Food sources1. enriched and whole grain products, porkE. Too much or too little:1. No known toxicity, no UL set2. Beriberi: thiamin deficiency disease (loss of appetite, weight, memory; confusion)a. Rare in U.S., due to enrichment of grainsb. Chronic alcohol abuse can lead to advanced form: Wernicke–Korsakoff syndrome, progressively damaging brain disorder3. Due to thiamin-deficient diet, and alcohol interferes with thiamin absorptionIII. Riboflavin (B2)A. Light-sensitive vitamin, abundant in milk1. Opaque containers preserve riboflavin contentB. Functions:1. Important for energy metabolism2. Keeps cells healthy3. Enhances functions of other B vitamins, such as niacin and B12C. Daily needs:1. Men: 1.2 mg/day; women: 1.1 mg/dayD. Food sources1. milk, yogurt, enriched cereals and grainsE. Too much or too little:1. Excess riboflavin excreted in urine: bright yellow color2. No UL set3. Deficiency symptoms rarely seen in healthy individuals eating a balanced diet:a. Sore throat, swelling inside mouth, inflamed and purplish-red tongue, dry and scaly lipsIV. Niacin (B3)A. Active forms: nicotinic acid and nicotinamide 2. Functions: needed for energy metabolism and to:a. Synthesize fat and cholesterolb. Keep skin cells and digestive system healthy3. Sometimes prescribed in high doses (40 times UL) by physicians to decrease blood LDL cholesterol and triglycerides, increase HDLC. Daily needs: men: 14 mg/day; women: 16 mg/day1. Can also be made in the body from the amino acid tryptophan: daily needs expressed in niacin equivalents (NE)a. Food sources: meat, fish, poultry, enriched whole-grain breads, fortified cerealsD. Protein-rich foods are good sources of tryptophanE. Too much or too little:1. Overconsumption of niacin supplements can cause flushing, nausea, vomiting, betoxic to liver, raise blood glucose levels: UL is 35 mg/day to prevent flushing.2. Pellagra: niacin deficiency disease (Four Ds)a. Dermatitis, diarrhea, dementia, deathb. Once common in South, due to corn-based dietV. FolateA. Naturally occurring form in foods B. Folic acid: synthetic form of folate added to foods and supplementsC. Functions: vital for DNA synthesis1. To create and maintain new cells, including red blood cells2. To help body use amino acids3. Folate deficiency during pregnancy can result in neural tube birth defects (examples: spina bifida, anencephaly).4. Reduces risks of some cancersD. Daily needs: 1. Adults need 400 µg of dietary folate equivalents (DFE)2. Folic acid is absorbed 1.7 times more efficiently than folate found naturally in foods 3. Women who might become pregnant need 400 µg extra from fortified foods/supplements4. Food sources: 5. Enriched grains (rice, pasta, breads, cereals) legumes, broccoli, asparagus, leafy greens such as spinachE. Too much or too little:1. UL = 1,000 µg/day of folic acid from enriched/fortified foods and supplementsa. Too much folic acid (not naturally-occurring folate in foods) masks vitamin B12 deficiency anemiab. Folate deficiency can lead to macrocytic anemiaVI. Vitamin (B12)A. Also called cobalamine because it contains the elementcobaltB. Requires intrinsic factor, protein made in stomach, in order to be absorbed in small intestine1. Pernicious anemia results in people who cannot make intrinsic factor: treatment requires B12 injection to bypass intestine2. Symptoms may take years to appear since B12 is stored in the liver C. Food sources: 1. Naturally occurring B12 only found in animal foods (meat, fish, poultry, dairy)2. Synthetic B12 found in fortified foods such as soy milk and some cerealsD. Too much or too little:1. No upper level set since no known risk from consuming too much B12, natural or synthetic2. Deficiency can cause macrocytic anemia (because folate can’t be utilized properly)a. Lack of intrinsic factor causes pernicious anemia, involves nerve damageVII. Vitamin CA. Also known as ascorbic acidB. Function: coenzyme to synthesize and use certain amino acids1. Needed to make collagen, most abundant protein in body, present in connective tissuea. Important for healthy bones, skin, blood vessels, teeth2. Also acts as an antioxidant3. Helps absorb iron from plant foods4. Breaks down histamine, cause of inflammationC. Daily Needs: 1. Men: 90 mg2. Women: 75 mg/day 3. Smokers: 35+ mg/day D. Too much or too little:1. UL = 2,000 mg/day to avoid nausea, stomach cramps, diarrheaa. People with a history of kidney stones or hemochromatosis (body stores too much iron) should avoid excess. 2. Deficiency disease: scurvyVIII. Pantothenic Acid and Biotin A. Functions: coenzymes that assist in energy metabolism of carbohydrates, fats, proteinB. Daily needs for adults: 1. Pantothenic Acid: 5 mg/day2. Biotin: 30 µg/dayC. Food Sources: 1. Widespread in foods such as whole grains and cereals, nuts, legumes, peanut butter, meat, milk, eggs2. Biotin also synthesized by intestinal bacteria D. Too much or too little:2. No UL, no known adverse effects from consuming too much of either vitamin3. Deficiencies of these vitamins are rare4. “Burning feet” syndrome seen in WWII prisoners of war in Asia due to pantothenic acid deficient diet of polished rice5. Biotin deficiency: hair loss, skin rash, fatigue, nausea, depression6. Avidin protein in raw egg whites binds biotin, preventing