Chapter 12 Fat Soluble Vitamins Vitamins Essential organic substances Produce symptoms when missing from diet Yield energy Basic functions Facilitate chemical reactions Function as co enzymes Vitamin Classifications Water soluble Fat soluble vitamin C Vitamins Storage of Vitamins in the Body Not readily excreted except vitamin K Generally lost from the body except vitamins B6 and B12 Excreted via urine Vitamins should be consumed Occasional lapse is harmless Vitamin Toxicity Fat soluble vitamins Can in the body Water soluble vitamins Some can cause Mostly likely due to Overview of vitamin digestion and absorption figure Fat Soluble Vitamins Overview in organic solvents Not readily Can cause toxicity Absorbed along with fat May cause deficiency Transported with fat In Vitamin A Active form preformed Vitamin A Retinal retinol and retinoic acid Dietary sources liver fish oils fortified dairy products and eggs Retinyl ester vitamin A FA can be converted to Vitamin A Dietary sources dark green and yellow orange vegetables and fruits Vitamin A Absorption Retinyl Ester Q Vitamin A Absorption Beta carotene Vitamin A Metabolism Conversion of Vitamin A compounds 900 micrograms retinol activity equivalent RAE Vitamin A Needs table RDA 700 micrograms RAE Daily Value Approximately 1 000 micrograms Average current intake meets Functions of Vitamin A Retinoids Growth and Development Vision Dermatology Carotenoid Functions Vitamin A Night blindness permanent blindness Follicular hyperkeratosis Vitamin A fat soluble vitamin stored in body Depends if from retinol or beta carotene Stored in liver lead to liver failure hypervitaminosis A Stored in adipocytes build up called hypercarotenemia Due to overzealous Margin of safety 80 300 Upper limit 3000 micrograms day retinol Vitamin D calciferol Fat soluble Essential in diet Sources Fatty fish cod liver oil fortified dairy products and some fortified breakfast cereals Can be by body Requirement sunlight times a week for minutes Chemistry Provitamins related compunds 7 dehydrocholesterol Cholecalciferol inactive vitamin D3 Calcitriol of vitamin D Vitamin D Activation Vitamin D calciferol Requirement Few foods contain vitamin D naturally Cod liver oil RDA s 15 g day from 15 g day from 51 70 yrs 20 g day from Vitamin D calciferol Absorption from food Micelle intestinal cell chylomicron etc Metabolism from liver to target cells or tissue final activation site If problem exists in either organ metabolism and activation is Functions of Vitamin D Regulates altered Along with the parathyroid hormone Regulates calcium phosphorus absorption Reduces excretion of calcium Regulates calcium deposition in bones Development maintenance Influences normal Linked to reduction of breast colon and prostate cancer Role in Bone Formation Causes calcium phosphorus to deposit in the bones Strengthens bones is the result of low vitamin D Bones fail to calcify normally Bone softness Breastfed infants with little sun exposure Bowing legs soft bones Rickets like disease in adults Bones lose minerals and become porous Vitamin D calciferol Toxicity No risk of toxicity from sun exposure Increased vitamin D leads to increased Calcium stores in kidneys and joints Monitor Adult margin of safety UL 50 g day Vitamin E Introduction Many claims some not fact Can not improve physical performance Enhance sexual performance Slow or prevent Slow progression of Antioxidant Prevents breakdown of Essential nutrient Fat soluble Vitamin E Chemistry Tocopherols alpha most active in humans beta gamma delta Absorption Micelle chylomicron lymph etc Vitamin E Functions Stabilizes cell membranes Reduces Other antioxidant compounds Glutathione peroxidase Superoxide dismutase Copper Zinc and Manganese Vitamin E Requirements Terminology TE equivalents RDA Sources mg day Oils Green leafy vegetable Liver Toxicity UL 1000mg day Vitamin K Synthesized by in the colon and absorbed Role in process Role in calcium binding potential Several forms found in the diet Vitamin K Chemistry Quinones family Plant derived Animal derived Synthetic form Rx from MD Absorption and metabolism Same as vitamin A D E Vitamin K Function Helps of protein blood clotting Fibrinogen fibrin traps RBC platelets activated by prothrombin vitamin K dependent Koagulation vitamin K Deficiency to see deficiency Possible with long term antibiotics Leads to hemorrhaging Vitamin K Requirements Women 90 g day Men 120 g day Sources Vitamin K Toxicity Liver green leafy vegetables cabbage family milk by bacteria in large bowel One way Causes breakdown of RBC RBC remnants accumulate and cause nerve damage Enrichment and Fortification add nutrients back to food after it was lost during processing enriched Whole grains contain original nutrients and grain cereal products need to be Thiamin riboflavin niacin folate iron add a nutrient to a food in which that nutrient does not naturally exist i e calcium fortified orange juice i e milk fortified with vitamin D Dietary Supplements Dietary Supplement Health and Education Act of 1994 DSHEA A A vitamin An A herb a botanical or a plant extract A Vitamin Mineral Supplementation Individuals that may benefit Things to look for No more than Daily Value certification Diet and supplement shouldn t exceed ULs Check for superfluous ingredients