Chapter 8 Outline Nutrients Involved in Energy Metabolism 1 Energy Metabolism a Vitamins and minerals i DO NOT DIRECTLY don t forget ii Are needed for generating energy from macronutrients iii B complex vitamins are particularly important in assisting energy metabolism iv Often function as coenzymes v Excess amounts excreted b Coenzyme organic molecule needed for enzyme activity riboflavin vitamin B6 niacin pantothenic acid and biotin function primarily in ii Folate iii Vitamins in the form of coenzymes are involved in just about every metabolic pathway and vitamin B12 function in cell regeneration and synthesis of red blood cells c Cofactor small chemically simple organic inorganic usually mineral ions i Thiamin metabolic processes 2 Nutrients Involved in Energy Metabolism a Thiamin Thiazole vitamin B1 main sources meats and grains i Metabolism of branched chain amino acids 1 Necessary for function of CHO AA dehydrogenase reactions e g PDH in glycolysis ii Assists in production of neurotransmitters DNA and RNA iii Good sources pork products sunflower seeds beans whole or enriched grains iv Deficiency beriberi leads to muscle wasting and nerve damage v Wernicke Korsakoff syndrome alcohol related need for thiamin increases b Riboflavin Vitamin B2 main sources meats and enriched foods dairy i Involved in oxidation reduction reactions 1 FAD FMN ii Part of coenzyme glutathione peroxidase antioxidant iii Good sources milk enriched foods meat iv Light sensitive use opaque milk cartons 1 Heat stable v Ariboflavinosis riboflavin deficiency sore throat swollen mucous membranes vi 1 3mg day men 1 1mg day women c Niacin vitamin B3 main sources meats and enriched grains i Two forms nicotinic acid and nicotinamide ii Required for oxidation reduction reactions of carbohydrates proteins and fats NADH NAD iii Can be made from amino acid nicotinic acid iv Good sources meat fish poultry enriched breads and cereals v Toxicity symptoms from supplements vi Pellagra severe niacin deficiency 1 Dermatitis diarrhea and dementia vii 16mg men 14mg women d Vitamin B6 found in meat and potatoes i Group of three related compounds ii Coenzyme in amino acid metabolism and gluconeogenesis 1 2 Necessary for metabolism of homocysteine 3 Associated with higher cardiovascular disease risk 1 iii Good sources meat fish poultry enriched cereals starchy vegetables iv Toxicity from high dose supplements nerve damage skin lesions v Deficiency involves skin blood anemia nerve tissues 1 Protein metab RBC neurotransmitter development e Folate found in grains and legumes damaged cells i Works with enzymes are critical in DNA synthesis amino acid metabolism and repair of ii Plays a special role in embryo development iii Deficiency issues include birth defects in infants anemia and heart disease iv Food sources include green leafy vegetables bread and grain products liver lentils asparagus and oatmeal f Vitamin B12 found in meats Includes a number of compounds that have a cobalt center surrounded by a ring structure i ii Works with coenzymes to assist DNA synthesis essential for nervous system functioning iii Food sources are animal and non plant products meat eggs dairy and seafood iv Deficiencies are rare reduced absorption or dietary intake g Pantothenic Acid meats and enriched foods i Absolutely essential for keytones carbs and protein metabolism 1 Necessary for acetyl CoA formation ii Required for synthesizing cholesterol steroids detoxification of drugs iii Good sources chicken beef egg yolk potatoes oat cereals tomato products iv No adverse effects from excess amounts v Deficiencies are very rare vi 5mg day for adults h Biotin i ii Coenzymes for fatty acid synthesis gluconeogenesis Is considered a B vitamin 1 Required as cofactor for carboxylases a Transfers CO2 and carboxyl in reactions 2 Pyruvate carboxylase pyruvate oxaloacetate iii Carbohydrate fat and protein metabolism iv Content determined for very few foods v Deficiency seen in large consumption of raw egg whites over time 1 Becomes bound by avidin and absorption blocked i Choline i Vitamin like substance metabolism cell membranes neurotransmission 1 Phosphotidylcholine or lecithin common in cell membranes of foods acetylcholine sk muscle contraction cardiac muscle relaxation ii Fat and cholesterol digestion iii Homocysteine metabolism iv Widespread in foods lecithin milk peanuts v Deficiency fat accumulation in the liver vi Toxicity from excess supplementation 1 Fishy body odor vomiting diarrhea 2 j Iodine Important for reproduction and growth i Component of thyroid hormones ii Hormones that regulate key metabolic reactions iii iv Good sources saltwater fish iodized salt foods prepared with iodized salt v Excess intake interferes with thyroid function vi Goiter enlarged thyroid gland vii Iodine deficiency disorders IDDs 1 Cretinism mental retardation stunted growth 2 Hypothyroidism decreased body temperature cold intolerance weight gain fatigue sluggishness viii Hyperthyroidism high levels of thyroid hormone caused by Graves disease 1 Weight loss increased heat production muscular tremors nervousness racing heartbeat and protrusion of the eyes k Chromium i Assists insulin in bloodstream Important for RNA and DNA metabolism ii iii Supports immune function and growth iv Dietary adequacy is controversial v Widely distributed in foods vi High dose supplementation safety is unknown vii Deficiency induced in labs inhibit glucose uptake into the cells causing a rise in blood glucose and insulin levels l Manganese viii Does chromium really affect body comp Based on the research NO i Cofactor involved in synthesis and urea formation bone matrix synthesis in protein fat and carbohydrate metabolism gluconeogenesis cholesterol ii Part of antioxidant enzyme superoxide dismutase iii Good sources whole grain foods iv Toxicity impairs the nervous system causing spasms and tremors m Sulfur i A major mineral ii Component of thiamin and biotin thiol containing group essential for macronutrient metab iii Part of amino acids methionine cysteine iv Required by liver for alcohol detoxification v Assists in maintaining acid base balance vi Obtained from protein 3 Inadequate B Vitamin Intake a Impacts ability to perform physical activity i Limited studies show poor work performance lower intensity and duration b Diets high in unenriched processed foods lack vitamin B i Some B vitamins lost in milling of grains are replaced by the enrichment process 3
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