Shop products for Chromium  Chromium for Weight Control Also known as: Glucose Tolerance Factor (GTF Chromium)
What is it?Chromium is an essential trace mineral that helps the body maintain normal blood sugar
levels. Where is it found?The best source of chromium is true brewer’s
yeast. Nutritional yeast and torula yeast do not contain significant amounts of chromium
and are not suitable substitutes for brewer’s yeast. Chromium is also found in grains and cereals,
though much of it is lost when these foods are refined. Some brands of beer contain
significant amounts of chromium. Why do dieters use it?*Some dieters say that chromium
- helps decrease body fat.
- helps improve muscle tone.
What do the advocates say?*Chromium is mainly used to stabilize blood sugar. The major role for chromium in weight
loss is to correct insulin resistance caused by chromium deficiency. However, assessing
chromium deficiency is difficult since normal blood levels are of such a low concentration
that they can escape detection by even the most sensitive instruments. Hair and toenail levels
can be evaluated, but these tests are not routinely done. Known causes of chromium deficiency include malnutrition, TPN (total parenteral nutrition),
alcoholism, and strenuous exercise, which can cause what is called “chromium
dumping.” How much is usually taken by dieters?The mineral chromium plays an essential role in the metabolism of carbohydrates and fats
and in the action of insulin. Chromium, usually in a form called chromium picolinate, has been
studied for its potential role in altering body composition. Chromium has primarily been
studied in body builders, with conflicting results.1 In people trying to lose
weight, a double-blind study found that 600 mcg per day of niacin-bound chromium helped some
participants lose more fat and less muscle.2 However, three other double-blind
trials have found no effect of chromium picolinate on weight loss,3 4
5 though in one of these trials lean body mass that was lost during a weight-loss
diet was restored by continuing to supplement chromium after the diet. A recent comprehensive
review combining the results of ten published and unpublished double-blind studies concluded
that chromium picolinate supplementation may have a small beneficial effect on weight
loss.6 Are there any side effects or interactions?In supplemental amounts (typically 50–300 mcg per day), chromium has not been found
to cause toxicity in humans. While there are a few reports of people developing medical
problems while taking chromium, a cause-effect relationship was not proven. One study
suggested that chromium in very high concentrations in a test tube could cause chromosomal
mutations in ovarian cells of hamsters.7 8 Chromium picolinate can be
altered by antioxidants or hydrogen peroxide in the
body to a form that could itself create free radical damage.9 In theory, these
changes could increase the risk of cancer, but so
far, chromium intake has not been linked to increased incidence of cancer in
humans.10 Chromium supplementation may enhance the effects of drugs for diabetes (e.g., insulin, blood
sugar-lowering agents) and possibly lead to
hypoglycaemia. Therefore, people with diabetes taking these medications should supplement
with chromium only under the supervision of a doctor. One report of severe illness (including liver and kidney damage) occurring in a person who was
taking 1,000 mcg of chromium per day has been reported.11 However, chromium
supplementation was not proven to be the cause of these problems. Another source claimed that
there have been reports of mild heart rhythm
abnormalities with excessive chromium ingestion.12 However, no published
evidence supports this assertion. Three single, unrelated cases of toxicity have been reported from use of chromium
picolinate. A case of kidney failure appeared after taking 600 mcg per day for six
weeks.13 A case of anaemia, liver dysfunction, and other problems appeared after
four to five months of 1,200–2,400 mcg per day.14 A case of a muscle disease
known as rhabdomyolysis appeared in a body builder who took 1200 mcg over 48
hours.15 Whether these problems were caused by chromium picolinate or, if so,
whether other forms of chromium might have the same effects at these high amounts remains
unclear. No one should take more than 300 mcg per day of chromium without the supervision of a
doctor. Preliminary research has found that vitamin C increases
the absorption of chromium.16 Are there any drug
interactions?
Certain medicines may interact with chromium. Refer to
drug interactions for a list of those medicines.
*Dieters and weight-management advocates may claim benefits for
chromium based on their personal or professional experience. These are individual opinions and
testimonials that may or may not be supported by controlled clinical studies or published
scientific articles on chromium. For more complete and detailed information, including
references and safety information, see Chromium as a
nutritional supplement. References1. Anderson RA. Effects of chromium on body composition and weight loss.
Nutr Rev 1998;56:266–70. 2. Crawford V, Scheckenbach R, Preuss HG. Effects of niacin-bound
chromium supplementation on body composition in overweight African-American women.
Diabetes Obes Metab 1999;1:331–7.)) 3. Bahadori B, Wallner S, Schneider H, et al. Effect of chromium yeast
and chromium picolinate on body composition of obese, non-diabetic patients during and after a
formula diet. Acta Med Austriaca 1997;24:185–7 4. Trent LK, Thieding-Cancel D. Effects of chromium picolinate on body
composition. J Sports Med Phys Fitness 1995;35:273–80 5. Volpe SL, Huang HW, Larpadisorn K, Lesser II. Effect of chromium
supplementation and exercise on body composition, resting metabolic rate and selected
biochemical parameters in moderately obese women following an exercise program. J Am Coll
Nutr 2001;20:293–306. 6. Pittler MH, Stevinson C, Ernst E. Chromium picolinate for reducing
body weight: meta-analysis of randomized trials. Int J Obes Relat Metab Disord
2003;27:522–9. 7. Sterns DM, Belbruno JJ, Wetterhahn KE. A prediction of chromium (III)
accumulation in humans from chromium dietary supplements. FASEB J
1995;9:1650–7. 8. Sterns DM, Wise JP, Patierno SR, Wetterhahn KE. Chromium (III)
picolinate produces chromosome damage in Chinese hamster ovary cells. FASEB J
1995;9:1643–9. 9. Speetjens JK, Collins RA, Vincent JB, Woski SA. The nutritional
supplement chromium (III) tris(picolinate) cleaves DNA. Chem Res Toxicol
1999;12:483–7. 10. Garland M, Morris JS, Colditz GA, et al. Toenail trace element levels
and breast cancer. Am J Epidemiol 1996;144:653–60. 11. Cerulli J, Grabe DW, Guathier I, et al. Chromium picolinate toxicity.
Ann Pharmacother 1998;32:428–31. 12. Shannon M. Alternative medicines toxicology: a review of selected
agents. J Clin Toxicol 1999;37:709–13. 13. Wasser WG, Feldman NS. Chronic renal failure after ingestion of
over-the-counter chromium picolinate. Ann Intern Med 1997;126:410 [letter]. 14. Cerulli J, Grabe DW, Gauthier I, et al. Chromium picolinate toxicity.
Ann Pharmacother 1998;32:428–31. 15. Martin WR, Fuller RE. Suspected chromium picolinate-induced
rhabdomyolysis. Pharmacotherapy 1998;18:860–2. 16. Offenbacher EG. Promotion of chromium absorption by ascorbic acid.
Trace Elements Electrolytes 1994;11:178–81. |