Protect cells and their membranes Protects LDLs from oxidation also reduces oxidation of polyunsaturated oils where we nd Vitamin D CL ASS NOTE S NOV 11 2013 NUTRI TION CONCEPTS The Fat Soluble Vitamins A D E and K Chapter 11 Notes Pt 2 Vitamin E Four different tocopherol compounds Alpha beta gamma and delta Position of methyl group Alpha tocopherol vitamin E activity in the body Antioxidant reduces oxidation Stop chain reaction of free radicals from producing more free radicals Reduce risk of heart disease Reduce in ammation Diseases of fat malabsorption cystic brosis Vitamin E De ciency Primary de ciency is rare Most common is lack of intake Secondary de ciency Effects of de ciency Erythrocyte hemolysis premature infants Effect of de ciency Not permanent can correct with treatment Neuromuscular dysfunction Red blood cells break open Spinal cord and retina Vitamin E Toxicity Toxicity is rare Liver regulates vitamin E concentrations UL is 65 times greater than recommended intake for adults Extremely high doses of vitamin E Vitamin E Recommendations and Foods RDA is based on alpha tocopherol only Vit E content in foods overestimated Page 1 Loss of muscle coordination and impaired vision and speech Vitamin E treatment corrects these symptoms May interfere with vitamin K activity Vit K important for clotting Enhance effect of blood clotting drugs hemorrhage Vitamin E blood thinning effect CL ASS NOTE S NOV 11 2013 NUTRI TION CONCEPTS Widespread in foods of Vitamin E predominant source Vegetable oils Seeds nuts Destroyed by heat processing and oxidation fresh foods best source overly processed foods are poor sources Review The primary role of vitamin E is as an antioxidant It inhibits the destruction of polyunsaturated fatty acids in foods and in the body ghts oxidation of low density lipoproteins which may offer protection from heart disease Review with Vit E in foods Vitamin E is easily destroyed by heat and oxidation which means that most cooked and processed convenient foods are poor sources The major dietary sources are vegetable oils which are polyunsaturated fatty acids Review of Vitamin E De ciency Toxicity A primary de ciency is rare because Vitamin E is widespread in foods A secondary de ciency is more common potentially due to the inability to absorb dietary lipids Excess of Vitamin E can lead to hemorrhaging due to interference with Vitamin K clotting activity Vitamin K Blood Clotting Role Can be obtained from non food source Made by bacteria in the GI tract Vitamin K Bone remodeling role Metabolism of bone proteins Vitamin K De ciency Primary de ciency is rare Secondary de ciency more common Acts primarily in blood clotting Essential for activation of several proteins in blood clotting process De ciency causes hemorrhaging and bleeding can occur in excess Prothrombin precursor of thrombin critical to the blood clotting Osteocalcin calcium binding protein essential for mineralization De ciency low bone density Fat absorption falters Some drugs disrupt vitamin K synthesis activity Antibiotics decrease synthesis because antibiotics kill bacteria in GI Tract then bacteria in GI Tract no longer contribute to Vitamin K Anticoagulant drugs interfere with metabolism activity of Vitamin K Page 2 CL ASS NOTE S NOV 11 2013 NUTRI TION CONCEPTS Newborn infants particularly susceptible Born with sterile intestinal tract another reason why breast feeding so important Mom passes along intestinal ora to the child Single dose of vitamin K given at birth in the heel Vitamin K Toxicity Not common No UL High doses can reduce effectiveness of anticoagulant drugs used to prevent blood clotting example of blood thinning drugs this can No adverse effects with high intakes Vitamin K Sources GI tract Food sources Half of person s need Stored in liver Green vegetables especially cabbage family Vegetable oils Review of Vitamin K Vitamin K s primary role is in blood clotting which is important to prevent hemorrhaging or excess bleeding Vitamin K can be made in the body by bacteria This supplies half of the body s needs Risk of de ciency increases if this process does not occur due to use of antibiotics Another reason secondary de ciency may occur is malabsorption of fat Secondary de ciencies are more common than primary de ciencies Review of Vitamin K Good sources of vitamin K include green vegetables especially from the cabbage family High intakes are only a concern for those who are taking anticoagulant drugs The Fat Soluble Vitamins In Summary Toxicities are possible b c body stores excesses Function of fat soluble vitamins together Vitamins E and A Vitamins A D and K Vitamins E and K Bone growth and remodeling Vit E protects vit A from oxidation Excess of Vitamin E can interfere with blood clotting action of Vitamin K Page 3 CL ASS NOTE S NOV 11 2013 NUTRI TION CONCEPTS Fat Soluble Vitamins Which fat soluble vitamins can be made in the body Which fat soluble vitamins are associated with bone remodeling Which fat soluble vitamins have anti oxidant roles A and E C is water soluble Vitamin A D and K Vitamins K and D Page 4
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