Vitamin K & Antioxidants NUT1602 E-Tutor 2018
Vitamin K O Can be obtained from non-food source O Bacteria in the GI tract O Acts primarily in blood clotting O Prothrombin O Metabolism of bone proteins O Osteocalcin O Low bone density O Other possible roles of vitamin K in the body
Blood-Clotting Process
Vitamin K Deficiency O Primary deficiency is rare O Secondary deficiency O Fat absorption falters O Some drugs disrupt vitamin K s synthesis and action O Newborn infants O Sterile intestinal tract O Single dose of vitamin K given at birth
Vitamin K Toxicity O Not common O No adverse effects with high intakes O No UL O High doses can reduce effectiveness of anticoagulant drugs
Vitamin K Sources O GI tract O Half of person s need O Stored in liver O Food sources O Green vegetables O Vegetable oils
The Fat-Soluble Vitamins In Summary O Toxicities are possible O Function of fat-soluble vitamins together O Vitamins E and A O Oxidation, absorption, and storage O Vitamins A, D, and K O Bone growth and remodeling O Vitamins E and K O Blood clotting
Highlight 11 Antioxidant Nutrients in Disease Prevention
Free Radicals and Disease O Free radical O Compound with one or more unpaired electrons O Look to steal electron from vulnerable compound O Electron-snatching chain reaction O Free radical production O Normal bodily functions O Environmental factors
Free Radicals and Disease O Antioxidants O Neutralize free radicals O Stable in various forms O Free radical attacks O Some are helpful O Most cause damage
Free Radicals and Disease O Free radical damage O Contribute to cell damage, disease progression, and aging O Polyunsaturated fatty acids in lipoproteins and membranes O Alter DNA, RNA, and proteins O Illicit inflammatory response
Free Radicals and Disease O Body s natural defenses and repair systems O Not 100 percent effective O Less effective with age O Oxidative stress O Cognitive performance O Cancer and heart disease O Arthritis and cataracts O Diabetes
Free-Radical Damage
Defending Against Free Radicals O System of enzymes against oxidants O Copper, selenium, manganese, and zinc O Antioxidant vitamins O Vitamin E O Defends body lipids O Beta-carotene O Defends lipid membranes O Vitamin C O Protects other tissues
Defending Against Cancer O Damage to cellular DNA O Antioxidants may protect DNA from this damage O Inverse relationship with vegetable intake O Positive relationship with beef and pork intake O Vitamin C as a prooxidant O Destruction of cancer cells O Vitamin E
Defending Against Heart Disease O Oxidized LDL scenario O Accelerate formation of artery-clogging plaques O Additional changes in arterial walls O Vitamin E protection O Supplements O Risk of supplement use by those who already have heart disease
Foods, Supplements, or Both? O Must replenish dietary antioxidants regularly O Foods O Antioxidants and other valuable nutrients O Antioxidant actions of fruits and vegetables are greater than their nutrients alone O Supplements O Contents are limited O Physiological levels vs. pharmacological doses