Chapters 7 8 VITAMINS MINERALS AND SUPPLEMENTS Nutrition and You 2e Vitamins and Minerals How Much Do You Need With a few exceptions these slides will not offer recommended amounts This is because people of varying ages sexes etc have varying nutrient needs For a great calculator to help determine your specific needs use the following site when the government shutdown is over http fnic nal usda gov fnic interactiveDRI Nutrition and You 2e Introduction to Vitamins Vitamins are essential nutrients They are flavorless organic compounds needed in small amounts micronutrients do not provide calories A vitamin deficiency can cause a variety of symptoms problems Nutrition and You 2e Introduction to Vitamins Some vitamins are antioxidants or substances that neutralize potentially harmful free radicals Vitamins A C and E and beta carotene pro vitamin A are antioxidants Free radicals are unstable oxygen containing molecules that can damage the cells of the body and possibly contribute to the increased risk of chronic diseases see Figure 7 4 in book for illustration and summary Nutrition and You 2e Introduction to Vitamins Vitamins differ in bioavailability or how well your body can absorb them from the food you eat Vitamins can be destroyed by air water or heat For this reason Don t overcook vegetables For example broccoli shouldn t be brown green beans shouldn t be mushy and collards should still be identifiable as green leafy vegetables Don t drown vegetables in water when cooking because nutrients can be lost in the cooking liquid Provitamins can be converted to vitamins by the body Example Beta carotene is converted to vitamin A Nutrition and You 2e Vitamins Organized By Food Group This figure below which comes from your book shows a general grouping of vitamins under the type of food likely to contain them Dairy is commonly fortified with Vitamins A and D Nutrition and You 2e Figure 7 1 Fat Soluble vs Water Soluble Vitamins Fat soluble Include A D E and K Require fat in order to be absorbed Can be stored in the body and can therefore be more toxic than water soluble vitamins Water soluble Include vitamin C and all B vitamins Absorbed with water and enter the bloodstream directly Nutrition and You 2e Not stored in the body you excrete what you don t need in urine but excesses still can be harmful Fat Soluble vs Water Soluble Nutrition and You 2e Figure 7 2 Sample Vitamins The following slides include some of the most notable vitamins However we need all of them in order to be at our healthiest Please see pages 228 232 261 and 263 270 in your text for a summary of vitamins their primary functions in humans and what effect deficiencies and excesses have on the body Nutrition and You 2e Vitamin A Functions Essential for healthy eyes Involved in cell differentiation reproduction and immunity by promoting gene expression for Healthy skin mucus membranes Bone growth Fetal development White blood cells to fight harmful bacteria Nutrition and You 2e Vitamin A Preformed vitamin A retinoids such as retinol retinoic acid retinal is only found in animal foods liver eggs fortified milk cheese Carotenoids including beta carotene are pigments which give color to carrots cantaloupe sweet potatoes spinach broccoli Carotenoids are converted to retinol in your body Absorbed better if consumed with fat dressing on salad oil for saut ing greens or roasting sweet potatoes Nutrition and You 2e Vitamin A Sources Compare to Your Needs Nutrition and You 2e Food sources vitamin A Vitamin A Too much or too little Excessive amounts of preformed vitamin A can accumulate to toxic levels Upper limit for adults 3 000 g Carotenoids in food are not toxic Excess carotenoids cause nonthreatening condition carotenodermia Chronic vitamin A deficiency causes night blindness Prolonged vitamin A deficiency leads to xerophthalmia Number one cause of preventable blindness in children mostly in developing countries As many as 500 000 children go blind each year due to vitamin A deficiency Vitamin A deficiency also associated with stunting of bones Nutrition and You 2e Vitamin D Called Sunshine Vitamin because vitamin D is made in the body with help of sunlight UV People with insufficient sunlight exposure must meet needs through diet including supplements such as cod liver oil also a source of omega 3 fats and vitamin D3 tablets Nutrition and You 2e Vitamin D Functions active form acts as a hormone Regulates two important bone minerals calcium Ca and phosphorus P Stimulates intestinal absorption of Ca and P to maintain healthy blood levels and build and maintain bones When dietary calcium is inadequate vitamin D and parathyroid hormone cause calcium to leave bones to maintain necessary blood levels May prevent type 2 diabetes and some cancers May help with immune system strength Nutrition and You 2e Vitamin D How to get it Sun exposure cannot meet everyone s vitamin D needs Skin pigment melanin and use of sunscreen reduce vitamin D production Sunlight intensity during winter in northern latitude including Atlanta not sufficient to make vitamin D Therefore vitamin D needs based on dietary sources Food sources fortified milk and yogurt fortified cereals fatty fish examples sardines salmon tuna Nutrition and You 2e Vitamin D Sources and Physical Needs Nutrition and You 2e Food source vitamin D Vitamin D Too much or too little Overuse of supplements may lead to hypervitaminosis D which causes hypercalcemia Damaging calcium deposited in kidneys lungs blood vessels heart UL 4 000 IU 100 g Rickets vitamin D deficiency disease in children On the rise in United States due to decreased milk consumption other factors The bones of children with rickets aren t adequately mineralized with calcium and phosphorus causing them to weaken and leading to bowed legs Osteomalacia adult equivalent of rickets Nutrition and You 2e The B Vitamins and Vitamin C Water soluble vitamins are not stored in body Excess is excreted in urine However routine intakes of excessive amounts can be harmful B vitamins share common role as coenzymes Help many enzymes produce chemical reactions in cells Nutrition and You 2e B Complex Vitamins There are 8 B vitamins a k a the B Complex and they were originally all thought to be the same vitamin Thiamin B1 Riboflavin B2 Niacin B3 Pantothenic Acid Pantothenate B5 Pyridoxine Pyridoxal Pyridoxamine B6 Biotin B7 Folic Acid B9 Cobalamin B12 The gaps e g B4 and B8 are no longer considered vitamins though they have Nutrition and