Chapter 8: Nutrients Involved In Energy MetabolismThe Body Requires Vitamins and Minerals to Produce Energy- A coenzyme is a molecule that combines with an enzyme to activate it and help it do its jobo Thiamin, riboflavin, vitamin b6, niacin, pantothenic acid, and biotin-energy metabolismo Folate and vitamin b12-cell regeneration and the synthesis of red blood cellsThiamin- Function:o Plays a critical role in the breakdown of glucose for energy Tpp is required for pyruvate dehydrogenase, the enzyme responsible for the conversion of pyruvate to acetyl-coao Assists in the production of dna and rna o Synthesis of neurotransmitters- Food Sources:o ham/pork products, sunflower seeds, beans, oat bran, mixed dishes that contain whole or enriched grains- Toxicity: None- Deficiency disease: o beriberi-muscle wasting and nerve damage- Deficiency is more serious with heavy alcohol consumption and limited food intakeo Alcohol related deficiency is Wernicke-korsakoff syndrome Generally accompanied by low thiamin intake, increases the need for thiamin tometabolize the alcohol, reduces thiamin absorption Symptoms: tremors, confusion , and impairment of memoryRiboflavin- Function:o Oxidation-reduction reactionso Flavin mononucleotide and flavin adenine dinucleotideo Part of the coenzyme required by glutathione peroxidase - Food Sources:o Milk is a good source, but is destroyed by light- Toxicity: None- Deficiency: o ariboflavinosis-sore throat, swelling of the mucous membrane Severe can impair the metabolism of vitamin b6 and niacinNiacin- Function:o Nicotinic acid and nicotinamide are essential for the formation of NAD and NADP Required for the oxidation-reduction reactions involved in the catabolism of carbohydrate, fat, and protein for energyo Unique vitamin in that the body can synthesize a limited amount from the amino acid tryptophan 60:1- Food Sources: o meat, fish, poultry, enriched bread products, and ready to eat cereals - Toxicity:o flushing: burning, tingling, and itching sensations accompanied by a reddened flush primarily on the face, arms, and chest. Liver damage, glucose intolerance, blurred vision,and edema of the eys can be seen with very large doses over long periods of time- Deficiency: o pellagra-rough skin Changes in the gastrointestinal tract, weakness, fatigue, anorexia, dermatitis, diarrhea, and dementiaVitamin B6- Function:o Pyridoxine, pyridoxal, pyridoxamineo It plays a critical role in transaminationo Gluconeogenesis- Food Sources: o meat, fish, poultry- Toxicity: none- Deficiency: o anemia, convulsions, depression, confusion, and inflamed, irritated patches on the skin. Skin, blood, and nervous system Blood levels of homocysteine increase because of incomplete metabolism or methionine Risk factor for cardiovascular diseasePantothenic Acid- Toxicity: none- Deficiency: rare- Function: o Metabolized into two major coenzymes coenzyme a and acyl carrier protein Essential for synthesis of fatty acids CoA fatty acid oxidation, ketone metabolism, and the metabolism of carbohydrate and proteinBiotin- Function:o Four carboxylase enzymes Carbon dioxide carrier and the carboxyl donor Fatty acid synthesis, gluconeogenesis, and carbohydrate, fat, and protein metabolismo Pyruvate carboxylase catalyzes the synthesis of oxaloacetate from pyruvate in the tca cycle- Deficiencies:o only seen in people who consume large amounts of egg whites (avidin) Tinning of hair, loss of hair color, red, scaly rash around the eyes, nose, and mouth, depression, lethargy, and hallucinations- Toxicity: noneCholine- Function:o Vitamin-like substance that is important for metabolism, the structural integrity of cell membranes, and neurotransmission o Fat digestion and transport of homocysteine metabolismo Important role in the metabolism and transport of fats and cholesterolo Found in bile- Food Sources: o widespread- Toxicity:o fishy body odor, vomiting, excess salivation, sweating, diarrhea, and low blood pressure- Deficiency: o increased fat accumulation in the liver, leads to liver damageIodine- Component of the thyroid hormones- Function: o body temperature, resting metabolic rate, and reproduction and growth- Food Sources: o saltwater fish, shrimp, seaweed, iodized salt, and white and whole-wheat breads made with iodized salt and bread conditioners- Toxicity: o too much iodine blocks the synthesis of thyroid hormones, goiter(enlargement of a thyroid gland) - Deficiency: o less iodine for the production of thyroid hormones, goitero Cretinism: mental retardation- Hypothyroidism: decreased body temperature, inability to tolerate cold environmental temperatures, weight gain, fatigue, sluggishness- Hyperthyroidism: commonly caused by graves disease, autoimmune disease that causes overproduction of thyroid hormoneso Weight loss, increased heat production, muscular tremors, nervousness, racing heart beat, and protrusion of the eyesChromium- Functiono Enhances the ability of insulin to transport glucose from the bloodstream into cellso Metabolism of rna and dna in immune function and growth- Food Sources: o Widely distributed in foods but concentrations in any particular food are not typically high Contamination can easily occur during the lab analysis Manganese - Function:o Cofactor involved in protein, fat, and carbohydrate metabolism, gluconeogenesis, cholesterol synthesis, and the formation of urea, the primary component of urineo Superoxide dismutase, an antioxidant enzymeo Protecting the body from oxidative damage- Food Sources:o whole gran foods- Toxicity:o impairment of the neuromuscular system, muscle spasms and tremors- Deficiency: rareSulfur- Function:o Major mineral and a component of the b-vitamins thiamin and biotino Part of the amino acids methionine and cysteine, sulfur helps stabilize the the d shapes of proteins in the bodyo Assists in the detoxification of alcohol and various drugso Maintain acid-base balanceo Obtain ample sulfur from protein containing foods- No dri specifically for sulfur- Toxicity: none- Deficiency:
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