Chapter 7Objectives for Chapter 7What Are Vitamins?Slide 4Vitamins Found Widely in MyPlatePowerPoint PresentationSlide 7Slide 8Slide 9Free RadicalsNormal and Impaired VisionSlide 12Slide 13Vitamin ASlide 15Animation: Vitamin A and Epithelial TissueSlide 17Animation: Vitamin A and the Visual CycleSlide 19Slide 20Slide 21Vitamin ESlide 23Slide 24Vitamin KSlide 26Slide 27Slide 28Vitamin DSlide 30Slide 31Slide 32Slide 33Animation: Activation of Vitamin DSlide 35The B Vitamins and Vitamin C Are Water-SolubleThiamin (B1)Slide 38Slide 39Riboflavin (B2)Slide 41Slide 42Niacin (B3)Slide 44Slide 45Vitamin B6Slide 47Slide 48FolateSlide 50Slide 51Slide 52Vitamin B12Slide 54Slide 55Slide 56Animation: Vitamin B12 AbsorptionVitamin CSlide 59Slide 60Pantothenic Acid and BiotinSlide 62Myths and Facts about the Common ColdAre There Other Important Nutrients?Slide 65Slide 66How Should You Get Your Vitamins?Slide 68Too Much of a Good Thing? New Vitamins and Cancer StudyToo Much of a Good Thing? New Vitamins and Cancer StudySlide 71Slide 72Slide 73© 2012 Pearson Education, Inc.Chapter 7Vitamins© 2012 Pearson Education, Inc.Nutrition and You, 2eObjectives for Chapter 7Describe the characteristics of vitamins.Explain the differences between fat-soluble and water-soluble vitamins, and classify each vitamin according to its solubility.Define the term antioxidant and explain which vitamins perform this function.List at least one good food source for each of vitamins A, D, E, and K.List at least one major role in the body for vitamins A, D, E, and K.Name at least one toxicity symptom for a fat-soluble vitamin.List at least one good food source for each of the water-soluble vitamins.Name at least one disease associated with a water-soluble vitamin deficiency.Explain the role of vitamin supplements in the diet.© 2012 Pearson Education, Inc.Nutrition and You, 2eWhat Are Vitamins?Vitamins are essential nutrientsTasteless, organic compounds needed in small amountsA deficiency will cause physiological symptomsConsuming too much of some vitamins will cause adverse effects© 2012 Pearson Education, Inc.Nutrition and You, 2eWhat Are Vitamins?Vitamins are either fat-soluble or water-solubleFat-soluble vitamins A, D, E, and K are absorbed with dietary fat and can be stored in bodyWater-soluble vitamins are absorbed with water and enter the bloodstream directlyNot stored in body, but excesses still harmful© 2012 Pearson Education, Inc.Nutrition and You, 2eVitamins Found Widely in MyPlateFigure 7.1© 2012 Pearson Education, Inc.Nutrition and You, 2eFigure 7.2Categorizing the Vitamins: Fat-Soluble and Water-Soluble© 2012 Pearson Education, Inc.Nutrition and You, 2eFigure 7.3Digesting and Absorbing Vitamins© 2012 Pearson Education, Inc.Nutrition and You, 2eTable 7.1© 2012 Pearson Education, Inc.Nutrition and You, 2eWhat Are Vitamins?Some vitamins function as antioxidants, substances that neutralize free radicals. Vitamins A, C, and E, and beta-carotene 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© 2012 Pearson Education, Inc.Nutrition and You, 2eFigure 7.4Free Radicals© 2012 Pearson Education, Inc.Nutrition and You, 2eFigure 7.5Normal and Impaired Vision© 2012 Pearson Education, Inc.Nutrition and You, 2eWhat Are Vitamins?Vitamins differ in bioavailability, which is the degree to which a nutrient is absorbed from foods and used in the bodyVitamins can be destroyed by air, water, or heatDon’t expose your produce to airA little water is enoughReduce cooking timeKeep your food coolOverconsumption of some vitamins can be toxicProvitamins can be converted to vitamins by the body© 2012 Pearson Education, Inc.Nutrition and You, 2eTable 7.2© 2012 Pearson Education, Inc.Nutrition and You, 2eVitamin AVitamin A: retinoids (retinol, retinal, retinoic acid)Preformed vitamin A only found in animal foods: liver, eggs, fortified milk, cheeseSome plants contain provitamin A carotenoids, which are converted to retinol in your body.Carotenoids, including beta-carotene, are pigments which give color to carrots, cantaloupe, sweet potatoes, spinach, broccoli.Like fat-soluble vitamins, absorbed more efficiently if fat present in intestinal tract© 2012 Pearson Education, Inc.Nutrition and You, 2eVitamin AFunctions:Essential for healthy eyesComponent of rhodopsin and iodopsin, light-sensitive proteins needed for vision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© 2012 Pearson Education, Inc.Nutrition and You, 2eAnimation: Vitamin A and Epithelial Tissue© 2012 Pearson Education, Inc.Nutrition and You, 2eMisc 7.1Vitamin A is Essential for Vision© 2012 Pearson Education, Inc.Nutrition and You, 2eAnimation: Vitamin A and the Visual Cycle© 2012 Pearson Education, Inc.Nutrition and You, 2eVitamin ADaily needs:Adult males: 900 micrograms (µg) retinol activity equivalents (RAE) Adult females: 700 µg RAE© 2012 Pearson Education, Inc.Nutrition and You, 2eFood source vitamin AVitamin A Sources and Physical Needs© 2012 Pearson Education, Inc.Nutrition and You, 2eVitamin AToo much or too little:Excessive amounts of preformed vitamin A can accumulate to toxic levels Upper limit for adults: 3,000 µg 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© 2012 Pearson Education, Inc.Nutrition and You, 2eVitamin EAlpha-tocopherol is most active form in bodyFunctions: Acts as a powerful antioxidantProtects cell membranes, prevents oxidation of LDL cholesterolActs as an anticoagulant, inhibiting formation of harmful clots inside bloodstreamDaily needs: Adults need 15 mg of alpha-tocopherol equivalents© 2012 Pearson Education, Inc.Nutrition and You, 2eVitamin EFood sources: vegetable oils, nuts, seeds, fortified cereals, some green leafy