Chromium1. Introduction Chromium is a lustrous, brittle, hard metal. Its colour is silver-gray and it can be highly polished. It does not tarnish in air, when heated it borns and forms the green chromic oxide. Chromium is unstable in oxygen, it immediately produces a thin oxide layer that is impermeable to oxygen and protects the metal below.Chromium main uses are in alloys such as stainless steel, in chrome plating and in metal ceramics. Chromium plating was once widely used to give steel a polished silvery mirror coating. Chromium is used in metallurgy to impart corrosion resistance and a shiny finish; as dyes and paints, its salts colour glass an emerald green and it is used to produce synthetic rubies; as a catalyst in dyeing and in the tanning of leather; to make molds for the firing of bricks. Chromium (IV) oxide (CrO2) is used to manufacture magnetic tapeChromium is mined as chromite (FeCr2O4) ore. Chromium ores are mined today in South Africa, Zimbabwe, Finland, India, Kazakihstan and the Philippines. A total of 14 million tonnes of chromite ore is extracted. Reserves are hestimated to be of the order of 1 billion tonnes with unexploited deposits in Greenland, Canada e USA.2. Natural food sourceFood SourcesThe best source of chromium is brewer's yeast, but many people do not use brewer's yeast because it causes bloating (abdominal distention) andnausea.Other good sources of chromium include the following:• Beef• Liver• Eggs• Chicken• Oysters• Wheat germ• Green peppers• Apples• Bananas• SpinachBlack pepper, butter, and molasses are also good sources of chromiumWhole grains, Bread, Brown rice, Meat, Broccoli, Mushrooms, Green beans, Brewer’s yeast, Beef, Beer, Chicken breast, Chicken legs, Calves’ liver, Cereals, Cheese, Eggs, Fish, Sea food, Corn, Potatoes, Diary products, and Fresh vegetables.Herbs are also rich in chromium. Herb sources of chromium include:Wild yam, Nettle, Catnip, Oat straw, Licorice, Horsetail, Yarrow, Red clover and Sarsaparilla.3. Metabolism of chromiumThe trivalent state of chromium (Cr3+) is that encountered in biological milieus and is responsible for its nutritional activity. The principal route by which trivalent chromium enters the body is the digestive system. Chromium in foods is present both in the inorganic form and as organic complexes. Intestinal absorption of chromium is low (0.5-2%), and the mechanism has not yet been fully elucidated. Absorbed chromium circulates as free Cr3+, as Cr3+ bound to transferrin or other plasma proteins, or as complexes, such as glucose tolerance factor (GTF)-Cr. Circulating trivalent chromium can be taken up by tissues, and its distribution in the body depends on the species, age, and chemical form. It is excreted primarily in the urine by glomerular filtration or bound to a low-mol-wt organic transporter. Chromium metabolism is still imperfectly understood. The use of 51Cr has nevertheless furnished valuable data concerning its transport and excretion.4. FunctionChromium is an essential trace element required for normal carbohydrate metabolism. The biological function of chromium is closely associated with that of insulin and most chromium-stimulated reactions are also insulin dependent. Proper chromium nutrition leads to a decreased requirement for insulin and also an improved blood lipid profile. Most fresh foods and minimally processed foods are good sources of dietary chromium. Inorganic chromium does not potentiate insulin action and must be converted to an organic biologically active form. An organic form of chromium capable of potentiating insulin has been isolated from brewer's yeast and was shown to contain: Cr, nicotinic acid and a combination of amino acids. Synthetic insulin potentiating organic chromium complexes containing chromium, nicotinic acid, glycine, cysteine, and glutamic acid or chromium, nicotinic acid and glutathione have been prepared. These complexes have not been purified to homogeneity since they dissociate during purification. Suitable analytical bioassays are available to measure total chromium and the organic biologically-active forms of chromium, respectively.5. Deficience symptomsWhat happens when someone has a Chromium deficiency?In general, only very small amounts of chromium are found in the human body, and specifically because a minimal amount of chromium can effectively carry out the balancing act of working with glucose, insulin and metabolism. The human body naturally has a low rate of absorption for chromium and expels far more than is retained.Those at risk for any amount of chromium deficiency are often those who suffer with Type-2 Diabetes, the elderly and athletes who perform high-intensity activities on a regular basis. These specific groups are advised to specialized diets or supplements, but it’s important to note that supplements are not treatments for conditions such as diabetes. Instead, the use of supplements and diet can be used to assist in glucose balance and potentially aid energy levels.
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Fatigue, Anxiety, Depression, Hyperactivity, Glucose intolerance, Irritability, Bipolar disease, Elevated blood cholesterol, Mood swings, Coronary blood vessel disease, Hypoglycemia, Stunted growth, Infertility, Learning disabilities, Obesity, Neuropathy, Increased triglycerides in blood, Decreased sperm count, and Diabetes.
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