CHAPTER 10: NUTRIENTS INVOLVED IN ENERGY METABOLISM AND BLOOD HEALTH

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1 CHAPTER 10: NUTRIENTS INVOLVED IN ENERGY METABOLISM AND BLOOD HEALTH Vitamins and minerals are required for proper metabolism, do not directly provide energy, are necessary for obtaining energy from the macronutrients and often function as coenzymes. Enzymes are proteins that accelerate the rate of a chemical reaction. Enzymes are required for all metabolic reactions. Coenzymes are molecules that combine with an enzyme to facilitate enzyme function. Some metabolic reactions require coenzymes. The B-complex vitamins are especially important for energy metabolism. The B-complex vitamins include: thiamin (B 1 ), riboflavin (B 2 ), niacin (B 3 ), the vitamin B 6 group, folate, vitamin B 12, pantothenic acid and biotin. B-vitamins directly associated with energy metabolism include: B-1 (THIAMIN) Vitamin portion of coenzyme TTP, which helps convert pyruvate to acetyl Co-A. It also helps with production of the acetylcholine. Thiamin pyrophosphate is a coenzyme required for carbohydrate metabolism. Thiamin also acts as a coenzyme for the metabolism of some fatty acids. Women = 1.1 mg/day; Men = 1.2 mg/day. Brewer s yeast, ham, wheat germ, sunflower seeds and mushrooms. Highly refined foods do not contain thiamin. Enriched foods and whole grains are good sources. Beriberi deficiency of thiamin resulting in muscle wasting and nerve damage. None known at this time. B-2 (RIBOFLAVIN) Helps build the structure of a few coenzymes used in the process of cell respiration, such as FAD. It is part of coenzymes involved in oxidation-reduction reactions. It is part of the antioxidant enzyme glutathione peroxidase. Women = 1.1 mg/day; Men = 1.3 mg/day. Milk, yogurt, meat and leafy greens. Ariboflavinosis riboflavin deficiency. Sore throat, swollen mucous membranes. None known at this time. B-3 (NIACIN; nicotinamide and nicotinic acid). It is part of the energy transport molecules known as NAD and NADP. Coenzyme assisting with metabolism of carbohydrates and fatty acids. 24

2 Women = 14 mg/day; Men = 16 mg/day. Unique point: the body can produce this vitamin from the amino acid tryptophan. It can also be acquired from eggs and milk. Good sources: meat, fish, poultry and enriched bread products. Pellagra severe niacin deficiency. Flushing, liver damage, glucose intolerance, blurred vision and edema of the eyes. B-6 GROUP (pyridoxal, pyridoxine and pyridoxamine). Group of 6 related compounds. Part of a coenzyme for more than 100 enzymes in amino acid metabolism. All three forms help create the enzyme PLP and are also used in metabolism of proteins, the formation of urea and the production of: serotonin, hemoglobin, lecithin and the nucleic acids. Group of 6 related compounds. Part of a coenzyme for more than 100 enzymes in amino acid metabolism. 1.3 mg/day. Women over 50 = 1.5 mg/day; Men over 50 = 1.7 mg/day. Uptake is impaired by alcohol. Good sources: enriched cereals, meat, fish, poultry, starchy vegetables, green leafy vegetables and the legumes. Microcytic anemia, dermatitis, convulsions, depression and confusion. Toxicity from supplements can result in nerve damage (neuropathy) and skin lesions. FOLIC ACID: (a/k/a folate or folacin) Is a coenzyme in the process of making various nucleic acids. It is also involved in neural tube formation, in the processing of B 12 and amino acid metabolism. Critical for cell division of very early embryos. 400 mcg/day. Leafy greens, organ meats, legumes, ready-to-eat cereals, enriched bread products and orange juice. Macrocytic anemia. Neural tube disorders, such as spinal bifida. Neurological damage and concealment of existing B 12 deficiencies. 25

3 COBALAMIN (B 12 ) Works with folate to make nucleic acids. Part of its structure is cobalt and it needs intrinsic factor in order to work. Part of coenzymes for blood formation. Required for nerve functioning. Required for homocysteine breakdown. 2.4 mcg/day. Meat, milk, cheese and eggs. Found only in animal-based foods. Pernicious anemia. Deficiency results in anemia, low energy, fatigue, shortness of breath and can lead to pernicious anemia. None known at this time. PANTOTHENIC ACID Main part of the structure of the enzyme Co-A in the process of cell respiration. Component of coenzymes for fatty acid metabolism. Required for building new fatty acids. 5 mg/day. It is easily destroyed by heat. Good sources: chicken, beef, egg yolk, potatoes, oat cereals and tomato products. Only observed in people specifically fed diets totally lacking in pantothenic acid. Deficiencies are very rare. None known at this time. No apparent toxicity from excess pantothenic acid. BIOTIN CO 2 carrier in the Krebs Cycle. It is a link to the process of gluconeogenesis. Part of structure of the coenzymes involved in metabolism of carbohydrates, fat and proteins. Important for gluconeogenesis. 30 mcg/day. Liver, egg yolks. Also produced in the gut. Its bioavailability can be limited by the protein avidin, which is found in raw egg whites. Biotin content has been determined for very few foods. Deficiency symptoms include hair thinning, dermatitis, loss of hair color, depression and a red facial rash. None known at this time. 26

4 Vitamin B imposters include: inositol, choline, lecithin, lipoic acid, PABA, bioflavenoids, CoQ (ubiquinone), B 15 (pangamic acid), B 17 (laetrile) and B-T (carnitine). Choline is a necessary nutrient for energy metabolism; it s just not a B-vitamin. Here are some choline details: Choline is a component of acetylcholine, which is a neurotransmitter that provides energy to your skeletal muscles and assists with memory functions within the brain. Choline is a vitamin-like substance. Assists in homocysteine metabolism. Women = 425 mg/day; Men = 550 mg/day. Choline is food in a wide variety of foods, including milk, eggs, liver and peanuts. Choline deficiency can produce a fatty liver. Toxicity can result in vomiting, excess salivation, sweating, diarrhea and low blood pressure. Toxicity can result from supplements. Minerals retain their chemical identity in the body. They can be either water or fat-soluble. Minerals can easily reach toxic levels in the body, so pay attention to RDA. They help maintain the body s fluid balance, and are called cofactors when they assist enzymes. Minerals cannot be destroyed by heat, cold, acid, air, or mixing. They are excreted from the body without being altered in any way. There are two categories of minerals: major (macro-) minerals are those that are present in the body structure in amounts greater than 5 grams. Trace minerals are present in the body in amount under 5 grams. Minerals involved in energy metabolism include: NAME OF MAJOR MINERAL SULFUR Stabilizes the structure of amino acids. Also is part of the structure of the vitamins biotin and thiamin and part of the hormone insulin. Required for detoxification of alcohol and drugs by the liver. There is no ; we consume what we need from any proteincontaining foods. All protein foods, including meat, fish, eggs, milk, legumes and nuts. Found in a few amino acids. Sufficient sulfur is synthesized from the protein in our diets. None known. Protein deficiency would occur first. Depresses growth rate in animals. IODINE Critical for the synthesis of thyroid (T 3 and T 4 ) hormones. Thyroid hormones regulate body temperature and resting metabolic rate. 27

5 150 µg/day. Good sources: saltwater fish, shrimp, iodized salt, milk and dairy products. Enlarged thyroid, Goiter, cretinism. Iodine deficiency can result in hypothyroidism, goiter and cretinism (a type of mental retardation that results from iodine deficiency during embryonic development). Also can result in an enlarged thyroid gland. Excess iodine blocks synthesis of thyroid hormones. The thyroid tries to make more hormones and this results in production of a goiter (enlarged thyroid). T 3 is known as tri-iodothyronine and is the active form of hormone produced by the thyroid gland (an endocrine gland located in the neck region of the body). The other form, T 4 (tetra-iodothyronine), is more commonly known as thyroxine. Iodine taken into the human body is modified into a form called iodide. Iodide plays a critical role in both thyroid hormones. These hormones regulate metabolism, body temperature, reproduction, growth, blood cell formation and nerve and muscle function. TSH (thyroid stimulating hormone) is produced by the anterior pituitary and regulates the production of the thyroid hormone. In the USA iodine is added to salt therefore, there is almost no iodine deficiency disease in America. CHROMIUM Associated with insulin to help regulate blood sugar levels. Assists insulin as it transports glucose from the blood into the cells. Women = 25 mcg/day Men = 35 mcg/day. Good sources include mushrooms, prunes, dark chocolate, nuts, whole grains, meat, fats and vegetable oils. Diabetes-like symptoms. Chromium deficiency inhibits glucose absorption by body cells. Unknown (from diet). Chromium picolinate supplements are advertised as: (1) terrific fat burners and (2) muscle builders. There is absolutely no scientific evidence that supports the supposed benefits of these supplements. MANGANESE Works as cofactor for enzymes. It is used in urea formation and also pyruvate conversion. It is a metalloenzyme. Part of the structure of the antioxidant enzyme superoxide. Women = 2.3 mg/day; Men = 1.8 mg/day. Widely distributed. Good sources include whole-grain foods, brown rice, pineapple, pine nuts, okra and spinach. NS and reproductive disorders. 28

6 Environmental, not dietary, is most likely. Can result in NS disorders. Toxicity impairs the nervous system causing spasms and tremors. Blood consists of a fluid component known as blood plasma and a cellular component, which includes red blood cells (RBC s; erythrocytes), white blood cells (WBC s; leukocytes) and platelets. RBC s transport oxygen, which is required for the reactions that release energy from nutrients. WBC s are defensive cells of the immune system and platelets assist with the process of blood coagulation (clotting). Without these specialized cells we would not be able to maintain life functions. Nutrients associated with maintenance of a healthy blood stream include: IRON Part of hemoglobin in RBC s, part of myoglobin in muscles, used in cell respiration as cofactor for many enzymes ad works with cytochromes in ETS (ETC). Women = 18 mg/day; Men = 8 mg/day. RDA varies based on age and gender. 27 mg/day for pregnant women. Red meat, poultry, fish, shellfish, legumes and dried fruits. Meat, poultry, fish, clams, oysters, enriched cereals and breads. Blue eye whites, lowered immunity, fatigue, iron poor blood. Causes microcytic anemia. Iron deficiency is the most common nutrient deficiency in the world. High risk people include infants, young children, preadolescent girls, premenopausal women, and pregnant women. Hemochromatosis, a genetic disorder that causes too much absorption of iron. Also joint disease, loss of hair and death by poisoning in kids. Iron overdose is the most common cause of poisoning deaths in children. Toxicity symptoms: nausea, vomiting, diarrhea, dizziness, confusion. There are two dietary sources of iron: heme bound and non-heme. The heme bound accounts for only about 10% of your daily dietary intake of iron but 23% of it will be absorbed; whereas the non-heme iron is about 90% of your daily intake but only 2 to 20% of it will be absorbed. Heme iron comes from animal sources. Meat, fish and poultry also contain MFP, a factor that promotes absorption of nonheme iron. Vitamin C also helps with the absorption of non-heme iron. Taking supplements with orange juice will not work because the vitamin C in the juice only helps with absorption of dietary iron not supplemental iron. Foods cooked in iron cookware will absorb iron salts from the cookware. Iron is absorbed into the body by special cells in the small intestine called mucosal cells. These mucosal cells are replaced about every three days. When shed in the feces they carry some iron with them. It is part of what gives the coloration to the feces. Specific proteins called mucosal ferritin proteins get iron from the GI tract and store it in the mucosal cells. When the body needs iron, mucosal ferritin releases some iron to another special protein called mucosal transferrin, which moves the iron to another protein, blood transferrin. Blood transferrin will transport the iron to the rest of the body. Much of the iron is moved into the bone marrow cells that help produce new red blood cells (erythrocytes, which contain hemoglobin). 29

7 ZINC In structure of many enzymes, the hormone insulin and genetic materials. It is also involved in sperm production. It is a coenzyme for hemoglobin production. It is part of superoxide dismutase antioxidant enzyme system and is active in the development and function of immune system. RDA is 8 mg/day for women, 11 mg/day for men. Note: fiber and phytates limit the bioavailability of zinc. Found in all protein containing food. Meats, whole grains, enriched grains and cereals. Low DNA synthesis, night blindness, anorexia and a low sperm count. Deficiencies are uncommon in the US. Symptoms are growth retardation, diarrhea and delayed sexual maturation. Renal failure and anemia. Toxicity can occur from supplements. Symptoms are intestinal pain, cramps, nausea, vomiting and loss of appetite. Zinc can be absorbed into intestinal cells, or carried in the blood by attachment to albumin (a plasma protein). A diet with too much zinc will limit the bioavailability of copper because copper competes with zinc to bind with metallothionein, the binding protein that brings zinc into the intestinal cells. Zinc also competes with iron to bind with blood transferrin, so too much zinc in the diet can affect your iron levels as well. Do not take excessive amounts of zinc in daily supplements it can seriously impair the uptake of copper, which can lead to heart muscle cell degeneration. High doses of zinc also enhance the development of atherosclerosis. Lozenges containing zinc gluconate can reduce head cold symptoms, but lozenges with zinc gluconate bound to flavor-enhancers have no value. COPPER Helps absorb iron into hemoglobin. Coenzyme for energy metabolism and for collagen production. Part of superoxide dismutase antioxidant enzyme system. Required for iron transport. RDA for adults is 900 mg/day. Organ meats, seafood, nuts, seeds, whole grain foods Copper deficiency is rare. Symptoms are anemia, reduced white blood cells and osteoporosis in children. Toxicity in not well studied in humans. Symptoms are intestinal pain, cramps, nausea, vomiting, diarrhea and liver damage. Copper works with some enzymes (ceruloplasmin and ferroxidases) to catalyze the oxidation of iron. Copper also works with other enzymes (superoxide dismutase) to help them act as antioxidants. Still other copper/enzyme combinations (such as lysyl oxidase) help with the production of big protein molecules called collagen molecules, which are used for support in many of the body s connective tissues. Others are involved in structure of the enzyme cytochrome-c oxidase, which is an important enzyme in the electron transport system (ETS, ETC) of the cell respiration process. 30

8 NAME OF FAT SOLUBLE K Aids in blood clotting and helps vitamin D with production of bone protein. Coenzyme for the synthesis of proteins involved in blood clotting. Women = 90 mcg/day; Men =120 mcg/day. Produced by E. coli in the intestine as well as acquired from liver, leafy greens and milk. Jaundice and excessive bleeding. Deficiencies can result in diseases that disturb absorption of fats. Reduction in effectiveness of anticoagulants. Review these energy-metabolism/blood health related disorders: Anemias Beri-beri Neural tube defects Pellagra Spinal bifida Vascular disease 31