Tell me about...
Chromium
What is
chromium?
Chromium is an essential trace mineral. It is bluish-white
in appearance and is found naturally only in combination with
other elements. Since it is not manufactured by the body,
it must be obtained from one's diet.
Why do
we need it?
Chromium is important in the metabolism of fats and carbohydrates.
It stimulates fatty acid and cholesterol synthesis and is
an activator of several enzymes.
Preliminary research has found that chromium improves glucose
tolerance in people with Turner's syndrome, a disease associated
with an inability to metabolize glucose. Other studies have
shown that chromium may increase blood levels of HDL cholesterol
(the "good" cholesterol). Research using a form
of chromium called chromium picolinate suggests that it may
increase fat loss and promote the gain of lean muscle tissue.
How much
chromium should I take?
There is currently no recommended daily allowance (RDA) for
chromium. However, the National Academy of Sciences has deemed
the following amounts to be safe and adequate in a normal
diet:
- Adult men: between 50-200 micrograms/day
- Adult women: between 50-200 micrograms/day
- Children aged 7-10: between 50-200 micrograms/day
- Infants: between 50-200 micrograms/day
- Pregnant/lactating women: between 50-200 micrograms/day
What are
some good sources of chromium?
The best source of chromium is true brewer's yeast; however,
most people cannot tolerate brewer's yeast because it causes
abdominal bloating and nausea. Other good sources of chromium
include beef, liver, eggs, chicken, oysters, wheat germ, green
peppers, apples, bananas, spinach, butter, black pepper and
molasses. Some brands of beer also contain significant amounts.
What can
happen if I don't get enough chromium?
Chromium deficiency has been linked to impaired glucose tolerance.
It is often seen in older people with non-insulin-dependent
diabetes mellitus and in infants with protein-calorie malnutrition.
Chromium supplementation helps manage these conditions, but
it not considered a substitute for other diabetes treatments.
What can
happen if I take too much?
Chromium has not been linked consistently with human toxicity.
One study suggested that very high concentrations of chromium
could cause chromosomal mutations in hamster cells, but that
effect has yet to be demonstrated in humans.
Two single, unrelated cases of toxicity have been reported.
A case of kidney failure appeared after taking 600 micrograms
per day for six weeks. A case of anemia, liver dysfunction,
and other problems appeared after approximately five months
of taking between 1,20024,000 micrograms of chromium picolinate
per day. Whether these problems were caused by chromium picolinate,
or whether other forms of chromium might have the same effects
at these high amounts, remains unclear. Nevertheless, it is
recommended that no one take more than 300 micrograms of chromium
per day without consulting a nutritionally-oriented doctor.
Other Resources :
The
More You Know About Minerals
The
More You Know About Nutrition
References
• Recommended
Dietary Allowances, 10th ed. Washington, D.C.: National
Academy Press, 1989.
• Murray M. Encyclopedia of Nutritional Supplements.
Rocklin, CA: Prima Publishing, 1996.
• Saner G, Yüzbasiyan V, Neyzi O, et al. Alterations
of chromium metabolism and effect of chromium supplementation
in Turner's syndrome patients. Am J Clin Nutr 1983;38:57478.
• Riales R, Albrink MJ. Effect of chromium chloride supplementation
on glucose tolerance and serum lipids including high-density
lipoprotein of adult men. Am J Clin Nutr 1981;34:267078.
• Wang MM, Fox EZ, Stoecker BJ, et al. Serum cholesterol
of adults supplemented with brewer's yeast or chromium chloride.
Nutr Res 1989;9:98998.
• Kaats GR, Blum K, Pullin D, Keither SC, Wood R. A randomized,
double-masked, placebo-controlled study of the effects of
chromium picolinate supplementation on body composition: a
replication and extension of a previous study. Curr Ther
Res 1998;59:37988.
• Wasser WG, Feldman NS. Chronic renal failure after
ingestion of over-the-counter chromium picolinate. Ann
Intern Med 1997;126:410 [letter].
• Cerulli J, Grabe DW, Gauthier I, et al. Chromium picolinate
toxicity. Ann Pharmacother 1998;32:42831.
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