HES 2823 1st Edition Lecture 18 Outline of Last Lecture I. Fat Soluble Vitamins (continued)A. Vitamin A (continued)1. Deficiency2. Food Source3. ToxicityOutline of Current Lecture I. Fat Soluble Vitamins (continued)A. Vitamin A (continued)1. Toxicity (continued)B. Vitamin D1. Function2. Deficiency3. Food Sources4. ToxicityC. Vitamin E1. Function2. DeficiencyCurrent LectureI. Fat Soluble Vitamins (continued)A. Vitamin A (continued)1. Toxicity (continued)a. Acute (continued)i. Polar bear liver has enough vitamin A to kill a human consuming itb. Chronici. 4x RDA over a time periodii. When over consumed, vitamin A enters the blood and acts like soap and dissolves membranes, attacking the liver firstiii. Beta-carotene is benign (not toxic), only the retinol form ofvitamin A isi. It is converted to vitamin A as neededii. Difficult to over consumeThese 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.iii. Believed that a diet rich in beta-carotene lowers the occurrence of canceriv. Finnish Smoker Study1. 7 year study with two groups of smokers given either vitamin A or a placebo2. Beta-carotene-consuming patients had 18% greater risk of cancer than placebo patients3. The consumption was through pills and not natural foodB. Vitamin D1. Cholecalciferol: animal source2. Ergocalciferol: plant source3. The body can make vitamin D; however most people cannot make enough on their owna. In the liver, cholesterol is formed into a particular compound that then enters the blood, so that when the blood passes beneath theskin and sunlight shines upon it, it is converted into cholecalciferolb. The arms, legs, and face are the best areas for sunlight absorption and conversionc. Recommendation: 15 minutes of sensible sun exposure produces enough vitamin D to lower dietary needs but not eliminate themd. One’s geographical location regarding the equator can effect the required dietary amountse. Darker skin colors require higher amounts of dietary vitamin Df. Remaining indoors, wearing protective clothing, and applying sunscreen heighten dietary requirements as well4. Functiona. Aids in the absorption of calcium, and thus bone formationi. Mineralization: the depositing of calcium and phosphorus into bone5. Deficiencya. In children: rickets (a disease in which bone does not mineralize properly, causing it to become soft)i. At birth, this is normal as bone takes time to mineralizeii. When this does not occur due to deficiency, legs bow under the force of body weight and “pigeon ribs” occur under the pressure of lungs against the rib cage as the ribs begin to point outwardiii. Swaddling clothes were originally used to prevent deformity in infantsiv. It was thought that rickets had been eliminated in the US 20-30 years ago, but this untrue as at risk, dark-skinned infants still experience this due to less sun absorptionb. In adults: osteomalacia (demineralized bone)i. The lack of vitamin D causes a lack of calciumii. The body pulls calcium from the bones, weakening themiii. No symptoms seen or felt typicallyiv. Gastric bypass malabsorption and malnutrition call for much examination in those patients, and 10-15 years ago, these tests found vitamin D deficiencies in 85% of those testedi. The obese are at a greater risk, but 40% of individuals have a marginal deficiencyii. Marginal deficiency is common in the US, increasing cancer and heart disease risks6. Food Sourcesa. No good, rich source in food supplyb. Fortified milk (also milk products, such as yogurt and cheese), some orange juices are fortified, fortified breakfast cerealsc. Cod liver oil historicallyi. Scandinavian countries – rickets eliminated due to cod liveroil routine supplements in 98% of children7. Toxicitya. Second most toxic vitamin after vitamin Ab. 4x RDA required to cause problemsc. Over absorption of calcium occurs, causing the excess to be dumped into soft tissue, like the kidneys, aorta, and musclesd. Cannot consume too much vitamin D from food naturallyC. Vitamin E1. Tocopheral: chemical name but alpha-tocopheryl acetate signifies is presence on pill bottles2. Functiona. Antioxidant: prevents oxidation (destruction) of important biochemicali. In the cell enzymes are converted into free radicals, which are very reactive compounds that need protection3. Deficiencya. Hemolytic anemia (fatigue because of lack of oxygen within a cell)i. Red blood cells rupture because the lipids in the cell membrane are oxidizedii. Uncommon but the at risk group is premature