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The Nutritional Relationships of Chromium David L

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The Nutritional Relationships of Chromium David L The Nutritional Relationships of Chromium David L. Watts, Ph.D., F.A.C.E.P.1 In 1959 a physiological role for chromium was determined. It is known that chromium is a 1. Trace Elements, Inc., P.O. Box 514, Addison. Texas 75001. constituent of the glucose tolerance factor urine.10 Doisy and co-workers reported that both the (GTF) and is synergistic with insulin in liver and hair levels of chromium in diabetics were promoting cellular glucose uptake. Chromium decreased proportionately.11 The chromium content deficiency produces an increase in the found in the hair is apparently related to and requirement for insulin. Chromium facilitates reflective of chromium nutritional status.12 An insulin at intracellular sites including the increase in TMA chromium levels have been ribosomes, and is known to stimulate some reported in patients receiving chromium enzymes in vitro. Chromium is important for supplementation.13 Thus TMA is a useful tool for the structure and metabolism of nucleic acids.1 evaluating chromium nutrition and tissue storage, 2 3 particularly since biological GTF is significantly active in hair follicles.14 Body Content and Requirements The total body content of chromium in the Conditions Associated with Chromium adult is estimated at 5 to 6 milligrams. Animal Deficiency studies have shown that chromium A number of physiological and disease concentrations are high in the spleen, testes, conditions are related to chromium status and have epididymis, and bone marrow. Tissue shown a correlate with TMA chromium levels. chromium levels are highest at birth and decline with age. The daily requirement for Diabetes chromium based upon urinary excretion studies Hambidge, et al, reported that children with has been estimated at 1 microgram per day. juvenile diabetes as a group had lower hair Dietary requirements range from 30 to 200 chromium levels than found in a normal control micrograms in order to compensate for its poor group.15 In adult diabetics the TMA chromium 4 absorption. levels were found low only in female patients.16 In the plasma, chromium is transported by its Some studies have reported conflicting results of attachment to transferrin. Hexavalent TMA chromium levels and suggest its usefulness chromium is better absorbed than the trivalent for determining the chromium status of groups form.5 rather than individuals. However, this may only be due to interpretive differences of TMA results. The Assessment of Chromium Status — Serum interpretive and therapeutic usefulness of TMA on A reliable range for serum chromium is individuals will be discussed later. lacking.6 At this time, serum determination is not a good indicator of body status since the Peripheral Neuropathy 7 serum is not in equilibrium with tissue stores. A case of peripheral neuropathy was reported in Studies report that serum and urinary chromium a patient on long term TPN. The patient developed are not affected significantly by chromium glucose intolerance, weight loss, and other 8 9 supplementation. metabolic disturbances that did not respond to increased insulin. After chromium supplementation, Tissue Mineral Analysis her metabolic dysfunctions improved along with Tissue mineral analysis (TMA) of human improvement in glucose tolerance and peripheral hair is a good method of assessing chromium neuropathy. Insulin requirements were also status. TMA is known to relate to body stores reduced.17 better than either serum or 17 Journal of Orthomolecular Medicine Vol. 4, No. 1, 1989 Cardiovascular Heart Disease (CHD) TMA levels. This is perhaps due to a similarity Experimental animal studies have revealed developing in higher intake of refined that chromium may be associated with the carbohydrates by Europeans. High glucose or development of atherosclerosis.18 19 Chromium sucrose intake results in chromium losses.27 Mertz deficiency has been noted with stated that animal protein is the best source of hypercholesterolemia,20 aortic plaques, and available chromium, and that insufficient protein corneal opacity.21 Schroeder, et al, found intake would be expected to lead to a low chromium levels in the aorta of subjects who chromium status,28 a condition observed in died of CHD to be lower than in those who died malnourished children. Spices are also substantially of accidental causes.22 Chromium high in chromium. supplementation has resulted in improved cholesterol levels and an increase in high density Hormonal Factors Contributing to Chromium lipoproteins (HDL). Stout presented evidence Deficiency — Insulin that insulin itself may be related to the patho- Like glucose, insulin also contributes to genesis of atherosclerosis.23 Studies have shown chromium deficiency. Insulin injection is known to a close relationship between insulin levels and increase chromium excretion.29 Since many patients cardiovascular disease. Serum insulin has been with adult onset diabetes have excessive insulin found to be elevated in myocardial infarct production,30 chromium deficiency would be patients as well as those who have expected in this group. Since both insulin and atherosclerosis, cerebral vascular disease, and glucose increase the excretion of chromium, it is peripheral vascular disease. Stout further important to consider the effects of food emphasized that "although diabetes is often consumption on serum insulin and glucose levels. regarded as a disease of insulin deficiency, Studies of the effects of different foods on serum insulin concentrations are commonly above glucose and insulin response (termed the glycemic normal in non-insulin-dependent diabetics who index (GI) have revealed surprising results. Foods are obese, as well as in patients using insulin." are categorized as percent (%) of GI. The higher the Insulin in high concentrations is known to GI%, the higher the insulin and glucose response. stimulate cholesterol synthesis in smooth muscle As an example, glucose is listed as 100%. High GI and lipid synthesis in the arterial wall. Low foods include carrots 92%; parsnips 98%; honey insulin levels have the opposite effect. Other 87%; cornflakes 80%; and white potato, 70%. Low endocrine factors are probably involved as well GI foods include lentils, 29%; and peanuts 13%.31 32 and will be discussed later. 33 Consumption of foods with a high GI may make Other conditions associated with human chromium replacement difficult. chromium deficiency include impaired growth, negative nitrogen balance, and decreased Estrogen respiratory quotient.24 Chromium stores often become depleted during pregnancy.34 Pregnancy produces a diabetogenic Factors Contributing to CR Deficiency — state characterized by insulin resistance.35 This Dietary results in excessive endogenous insulin secretion,36 The chromium content of foods is markedly thereby contributing to chromium excretion or reduced by processing and refining. Losses are transfer to the fetus. It is likely that excess estrogen as high as 90 percent in some foods. Earlier contributes to the hyperinsulinism during studies that compared autopsied tissue in the pregnancy. Insulin levels are found to be highest in U.S. with those of other countries found that the the last trimester. Estrogen therapy also contributes average tissue chromium content was 2 to 12 to the same metabolic effect of increased insulin times higher than those of the U.S.25 26 production,37 38 either directly or indirectly.39 However, TMA studies of over two thousand Europeans at Trace Elements, Inc. over the past Thyroid two years do not show a major difference in The thyroid hormone and insulin are 18 The Nutritional Relationships of Chromium mutually competitive.40 41 42 43 Thyroid activity Obviously emotional changes trigger hormonal may directly or indirectly affect chromium status. responses. In clinical practice one often sees Low thyroid function may allow increased prediabetic patients who develop manifestations of insulin secretion resulting in chromium loss, or glucose intolerance following stressful or increased insulin production may suppress traumatic events. These patients may become thyroid function or expression. At this time the emotionally stressed following an auto accident, thyroid-insulin relationship remains speculative. for example. Their insulin and glucose levels may However a prevalence of thyroid failure develop severe swings, resulting in instability and occurring in diabetics has been reported.44 thus poor response to therapy. This type of trauma results in the syndrome termed post traumatic Hyper-Parathyroidism (HPTH) dysinsulinism. It is not uncommon for predisposed HPTH may contribute to chromium deficiency individuals to develop diabetes following this type due to hyperinsulinism. HPTH has been of stress episode. associated with hyperinsulinism due to tumours of the pancreatic islets, pituitary, or other organs. Minerals Symptoms of HPTH are not unlike those of Figure 1 shows the minerals that are diabetes.45 antagonistic to chromium.48 49 The solid lines indicate a direct antagonism either on a metabolic Stress or absorptive level. The broken lines indicate an Physiological or emotional stress is known to indirect antagonistic relationship. A patient with affect chromium status. The stress of infections increased tissue retention of any one or increases chromium excretion. Patients suffering combination of these essential and toxic elements from myocardial infarction commonly develop can be expected to have increased chromium hyperglycemia and glucose intolerance without requirements. Depending upon the individual,
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