The Water-Soluble Vitamins: B Vitamins and Vitamin CThe Vitamins – An OverviewSlide 3Slide 4Slide 5Minimizing Nutrient LossesSlide 7Dose Levels and EffectThe B VitaminsThe B Vitamins- DRIsThe B Vitamins – Thiamin (B1)The B Vitamins – ThiaminSlide 13Thiamin in Selected FoodsThe B Vitamins – Riboflavin (B2)The B Vitamins – RiboflavinRiboflavin in Selected FoodsThe B Vitamins – NiacinSlide 19Niacin-Deficiency Symptom – The Dermatitis of PellagraSlide 21Niacin in Selected FoodsThe B Vitamins – BiotinSlide 24The B Vitamins – Pantothenic AcidThe B Vitamins – B6Slide 27Vitamin B6 in Selected FoodsThe B Vitamins – FolateSlide 30Normal Blood Cells & Blood Cells in Macrocytic Anemia ComparedSlide 32Decreasing Prevalence of NTDs since Folate FortificationSlide 34Slide 35Slide 36Folate in Selected FoodsThe B Vitamins – Vitamin B12Slide 39Slide 40Slide 41The B Vitamins – CholineInteractions among the B VitaminsMetabolic Pathways Involving B VitaminsB Vitamin-Deficiency Symptoms – Tongue Glossitis & CheilosisThe B Vitamins – In ConcertVitamin C – RolesSlide 48Slide 49Vitamin C – RecommendationsVitamin C – DeficiencyVitamin C-Deficiency Symptoms – Scorbutic Gums & Pinpoint HemorrhagesVitamin C – ToxicityVitamin C – Food SourcesVitamin C in Selected FoodsThe Water-Soluble The Water-Soluble Vitamins: B Vitamins: B Vitamins and Vitamins and Vitamin CVitamin CChapter #10Chapter #10Dr. Alisha RovnerDr. Alisha RovnerFall 2013Fall 2013NTDT 200NTDT 200The Vitamins – An OverviewThe Vitamins – An Overview•Vitamins differ from energy-yielding nutrients:•Structure- Individual units not linked together like glucose or amino acids•Function- No energy yielded•Food contents- amount measured in mircrograms (υg) or milligrams (mg) not grams•Similarities to energy-yielding nutrients:•Vital to life, organic, available from foodsThe Vitamins – An OverviewThe Vitamins – An Overview•Bioavailability•Quantity provided by food•Amount absorbed and used by body•Factors influencing bioavailability:•Efficiency of digestion•Nutrition status•Method of food preparation•Source of nutrient•Other foods consumed at same timeThe Vitamins – An OverviewThe Vitamins – An Overview•Precursors- some vitamins available from foods in inactive forms•In body, precursor is converted to active form in body•When measuring person’s vitamin intake need to count- (1) amount of active vitamin and (2) amount from precursorsThe Vitamins – An OverviewThe Vitamins – An OverviewOrganic nature•Can be destroyed and unable to function•Must be handled with care during storage and in cooking•Ways to minimize nutrient lossesMinimizing Nutrient LossesThe Vitamins – An OverviewThe Vitamins – An Overview•Solubility•Affects absorption, transport, and excretion•Water-soluble•Move directly into blood•Most travel freely•Fat-soluble•Enter lymph and then blood•Require transport proteinsDose Levels and EffectDose Levels and EffectToxicity•More is NOT necessarily better•Excessive intakes can be DANGEROUS!•Levels higher than ULThe B VitaminsThe B Vitamins•Vitamins do NOT provide the body with fuel for energy•Coenzymes•Assist enzymes with release of energy•Without coenzyme, an enzyme cannot functionThe B Vitamins- DRIsThe B Vitamins- DRIs•Recommended Dietary Allowance (RDA)•Thiamin, Riboflavin, Niacin, Vitamin B6, Folate, Vitamin B12, Vitamin C•Adequate Intake (AI)•Biotin, Pantothenic acid, Choline•Tolerable Upper Limit (UL)•Niacin, Vitamin B6, Folate, Choline, Vitamin CThe B Vitamins – Thiamin (BThe B Vitamins – Thiamin (B11))•Part of coenzyme thiamin pyrophosphate (TPP) which assists in energy metabolism•Conversion of pyruvate to acetyl CoA•TCA cycle•Occupies site on membranes of nerve cells, important for nerve activity and muscle activityThe B Vitamins – ThiaminThe B Vitamins – Thiamin•RDA •Men 1.2 mg/day, women 1.1 mg/day •Deficiency•Malnourished and alcoholics at risk •Beriberi•Dry – nervous system •Wet – cardiovascular system•Toxicity- No adverse effects, no ULThe B Vitamins – ThiaminThe B Vitamins – Thiamin•Food sources•Pork richest source•Enriched grains typically make greatest contribution to day’s intake•Prolonged cooking destroys thiamin, leaches into water when boiling or blanching foods•Cooking methods that conserve thiamin include steaming and microwavingThiamin in Selected FoodsThiamin in Selected FoodsThe B Vitamins – Riboflavin (BThe B Vitamins – Riboflavin (B22))•Serves as coenzyme in energy metabolism•Flavin mononucleotide (FMN)•Flavin adenine dinucleotide (FAD)•RDA- Men 1.3 mg/day, Women 1.1 mg/day •Deficiency- Inflammation of membranes•Toxicity- No ULThe B Vitamins – RiboflavinThe B Vitamins – Riboflavin•Food sources•Milk and milk products•Whole grain or enriched bread and cereal•Vegans and others who don’t consume milk must rely on other sources•Destruction of riboflavin•Ultraviolet light (milk not sold in clear containers)•Irradiation•Not destroyed by cookingRiboflavin in Selected FoodsRiboflavin in Selected FoodsThe B Vitamins – NiacinThe B Vitamins – Niacin•Two chemical structures•Nicotinic acid•Nicotinamide (major form of niacin in blood)•Part of coenzymes Nicotinamide adenine dinucleotide (NAD) and NADP (its phosphate form) used in energy metabolism•Unique among B vitamins because the body can make it from the amino acid tryptophanThe B Vitamins – NiacinThe B Vitamins – Niacin•RDA stated in niacin equivalents (NE)•Body manufacturers niacin from tryptophan after protein synthesis needs have been met•1 NE= 1 mg niacin or 60 mg tryptophan•Men 16 mg NE/day, Women 14 mg NE/day•Deficiency- Pellagra•Symptoms- 4 D’s (Diarrhea, Dermatitis, Dementia and eventually Death)Niacin-Deficiency Symptom – Niacin-Deficiency Symptom – The Dermatitis of PellagraThe Dermatitis of PellagraThe B Vitamins – NiacinThe B Vitamins – Niacin•Toxicity•Naturally occurring, no harm•Supplements or drugs•“Niacin flush”- doses 3-4x RDA •Potential health benefits of large doses of nicotinic acid (LDL, HDL, adiponectin)•Food sources•Protein rich foods (meat, fish, poultry, pb)•Less vulnerable to food preparation lossesNiacin in Selected FoodsNiacin in Selected FoodsThe B Vitamins – BiotinThe B Vitamins – Biotin•Coenzyme that carries activated carbon dioxide•Critical in
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