Chromium deficiency

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Chromium deficiency
Classification and external resources
Chromium
ICD-10 E61.4
DiseasesDB 2625

Chromium deficiency is a disorder that results from an insufficient dietary intake of chromium. If such a deficiency ever occurs in people eating a normal diet is debated,[1][2] and clear cases of deficiency have only been observed in hospital patients who were fed defined liquid diets intravenously for long periods of time.[3] Although chromium is an essential trace element in humans the basis for this need is not fully understood, since no chromium-containing biomolecules with beneficial effects have been characterized.[4][5]

Contents

[edit] Use of chromium in the body

Trivalent chromium is the state that has been discussed as a possible essential trace metal, hexavalent chromium is toxic and mutagenic.

Trivalent chromium was thought to be a constituent in the so-called glucose tolerance factor (GTF). GTF has been hypothesised to be a metalloprotein complex that is formed when the oligopeptide chromodulin, which consists of the four amino acid residues aspartate, cysteine, glutamate, and glycine, is bonded with four (Cr3+) centers. Some studies have suggested that chromodulin could bind to the insulin receptor and stimulate insulin signaling.[6] However, the existence of this glucose tolerance factor remains uncertain, a recent academic review concluded that "To date, no chromium-containing glucose tolerance factor has been characterized, the purpose of the low-molecular-weight chromium-binding protein is questionable, and no direct interaction between chromium and insulin has been found."[5]

[edit] Dietary guidelines

The US dietary guidelines for adequate daily chromium intake were lowered in 2001 from 50–200 µg for an adult to 30–35 µg (adult male) and to 20–25 µg (adult female).[7] These amounts were set to be the same as the average amounts consumed by healthy individuals, consequently it is thought that few Americans are chromium deficient.[8]

Approximately 2% of chromium of ingested chromium(III) is absorbed, with the remainder being excreted in the feces. Amino acids, vitamin C and niacin may enhance the uptake of chromium from the intestinal tract.[9] After absorption, this metal accumulates in the liver, bone, and spleen.

Trivalent chromium is found in a wide range of foods, including: whole-grain products, processed meats, high-bran breakfast cereals, coffee, nuts, green beans, broccoli, spices, and some brands of wine and beer.[9] Most fruits and vegetables and dairy products only contain low amounts.[3] Most of the chromium in people's diet comes from processing or storing food in pans and cans made of stainless steel, which can contain up to 18% chromium.[3]

The amount of chromium in the body can be decreased as a result of a diet high in simple sugars, which increases the excretion of the metal through urine.[10] Because of the high excretion rates and the very low absorption rates of most forms of chromium, acute toxicity is uncommon.

[edit] Symptoms

The symptoms of chromium deficiency caused by long-term total parenteral nutrition are severely impaired glucose tolerance, a loss of weight, and confusion.[11] Another patient also developed nerve damage (peripheral neuropathy).[12]

[edit] Supplementation

Chromium picolinate is the most commonly used synthetic supplement. However, recent studies "have concluded that such supplements have no demonstrated effects on healthy individuals."[4] A meta-analysis in 2002 found no effect on blood glucose or insulin in healthy people, and the data were inconclusive for diabetics.[13] Subsequent trials gave mixed results, with one finding no effect in people with impaired glucose tolerance,[14] but another seeing a small improvement in glucose resistance.[15] In a 2007 review of these and other clinical trials it was again concluded that chromium supplements had no beneficial effect on healthy people, but that there might be an improvement in glucose metabolism in diabetics, although the authors stated that the evidence for this effect remains weak.[16]

This supplement is purported to correct imbalances in glucose metabolism due to chromium deficiency, even though the occurrence of such a deficiency is extremely rare in countries where the supplement is sold. The mechanism by which this complex enters the cells in the body differs from that for the introduction of trivalent chromium found naturally in food does, and for this reason the safety or this supplement is debatable, since chromium is known to be a toxic metal.[17] For chromium to be used in the cells it must be released from chromium picolinate, in a process in which the chromium becomes reduced. This process can possibly lead to the formation of dangerous reactive oxygen species.

Although it is controversial if supplements should be taken by healthy adults eating a normal diet,[2] chromium is needed as a component of the defined liquid diet that is given to patients receiving total parenteral nutrition (TPN), since deficiency can occur after many months of this highly restricted diet.[11] As a result chromium is added to normal TPN solutions,[18] although the trace amounts from even in supposedly "chromium free" preparations may be enough to prevent deficiency in some individuals.[19] Indeed, a recent paper in The Lancet suggested that adding chromium to feeding solutions given to children produces excessive levels of this metal in their bodies.[20]

[edit] References

  1. ^ Jeejeebhoy KN (1999). "The role of chromium in nutrition and therapeutics and as a potential toxin". Nutr. Rev. 57 (11): 329–35. PMID 10628183. 
  2. ^ a b Porter DJ, Raymond LW, Anastasio GD (1999). "Chromium: friend or foe?". Arch Fam Med 8 (5): 386–90. doi:10.1001/archfami.8.5.386. PMID 10500510. 
  3. ^ a b c Review of Chromium Expert group on vitamins and minerals: Review of chromium, 12 August 2002
  4. ^ a b John B. Vincent "Chromium: Biological Relevance" in Encyclopedia of Inorganic Chemistry, John Wiley: New York, 2005.
  5. ^ a b Stearns DM (2000). "Is chromium a trace essential metal?". Biofactors 11 (3): 149–62. PMID 10875302. 
  6. ^ Vincent JB (2004). "Recent advances in the nutritional biochemistry of trivalent chromium". Proc Nutr Soc 63 (1): 41–7. doi:10.1079/PNS2003315. PMID 15070438. 
  7. ^ Trumbo P, Yates AA, Schlicker S, Poos M (2001). "Dietary reference intakes: vitamin A, vitamin K, arsenic, boron, chromium, copper, iodine, iron, manganese, molybdenum, nickel, silicon, vanadium, and zinc". J Am Diet Assoc 101 (3): 294–301. doi:10.1016/S0002-8223(01)00078-5. PMID 11269606. 
  8. ^ Vincent JB (2004). "Recent advances in the nutritional biochemistry of trivalent chromium". Proc Nutr Soc 63 (1): 41–7. doi:10.1079/PNS2003315. PMID 15070438. 
  9. ^ a b Lukaski HC (1999). "Chromium as a supplement". Annu. Rev. Nutr. 19: 279–302. doi:10.1146/annurev.nutr.19.1.279. PMID 10448525. 
  10. ^ Kozlovsky AS, Moser PB, Reiser S, Anderson RA (1986). "Effects of diets high in simple sugars on urinary chromium losses". Metab. Clin. Exp. 35 (6): 515–8. PMID 3713513. 
  11. ^ a b Freund H, Atamian S, Fischer JE (1979). "Chromium deficiency during total parenteral nutrition". JAMA 241 (5): 496–8. doi:10.1001/jama.241.5.496. PMID 104057. 
  12. ^ Jeejeebhoy KN, Chu RC, Marliss EB, Greenberg GR, Bruce-Robertson A (1977). "Chromium deficiency, glucose intolerance, and neuropathy reversed by chromium supplementation, in a patient receiving long-term total parenteral nutrition". Am. J. Clin. Nutr. 30 (4): 531–8. PMID 192066. 
  13. ^ Althuis MD, Jordan NE, Ludington EA, Wittes JT (2002). "Glucose and insulin responses to dietary chromium supplements: a meta-analysis". Am. J. Clin. Nutr. 76 (1): 148–55. PMID 12081828. 
  14. ^ Gunton JE, Cheung NW, Hitchman R, et al (2005). "Chromium supplementation does not improve glucose tolerance, insulin sensitivity, or lipid profile: a randomized, placebo-controlled, double-blind trial of supplementation in subjects with impaired glucose tolerance". Diabetes Care 28 (3): 712–3. doi:10.2337/diacare.28.3.712. PMID 15735214. 
  15. ^ Singer GM, Geohas J (2006). "The effect of chromium picolinate and biotin supplementation on glycemic control in poorly controlled patients with type 2 diabetes mellitus: a placebo-controlled, double-blinded, randomized trial". Diabetes Technol. Ther. 8 (6): 636–43. doi:10.1089/dia.2006.8.636. PMID 17109595. 
  16. ^ Balk EM, Tatsioni A, Lichtenstein AH, Lau J, Pittas AG (2007). "Effect of chromium supplementation on glucose metabolism and lipids: a systematic review of randomized controlled trials". Diabetes Care 30 (8): 2154–63. doi:10.2337/dc06-0996. PMID 17519436. 
  17. ^ Bagchi D, Stohs SJ, Downs BW, Bagchi M, Preuss HG (2002). "Cytotoxicity and oxidative mechanisms of different forms of chromium". Toxicology 180 (1): 5–22. doi:10.1016/S0300-483X(02)00378-5. PMID 12324196. 
  18. ^ Anderson RA (1995). "Chromium and parenteral nutrition". Nutrition 11 (1 Suppl): 83–6. PMID 7749258. 
  19. ^ Kien CL, Veillon C, Patterson KY, Farrell PM (1986). "Mild peripheral neuropathy but biochemical chromium sufficiency during 16 months of "chromium-free" total parenteral nutrition". JPEN J Parenter Enteral Nutr 10 (6): 662–4. PMID 3099015. 
  20. ^ Moukarzel AA, Song MK, Buchman AL, et al (1992). "Excessive chromium intake in children receiving total parenteral nutrition". Lancet 339 (8790): 385–8. doi:10.1016/0140-6736(92)90078-H. PMID 1346659. 

[edit] Further reading

  • William T. Cefalu and Frank B. Hu. (2004). Role of Chromium in Human Health and in Diabetes. Diabetes Care,27:2741-2751.
  • Journal of the American College of Nutrition, Vol 4, Issue 1 107-120, Copyright © 1985 by American College of Nutrition
  • http://ods.od.nih.gov/factsheets/chromium.asp

[edit] External links

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