Low chromium levels may raise heart attack risk

NEW YORK (Reuters Health) – Low body levels of chromium, a
mineral involved in carbohydrate and fat metabolism, are
associated with an increased risk of heart attack, according to
a new report. However, the value and safety of chromium
supplementation remains to be determined.

Chromium deficiency leads to blood sugar problems that
cannot be controlled with insulin, researchers explain in the
American Journal of Epidemiology, but the association of
chromium intake with heart-related outcomes is largely unknown.

Dr. Eliseo Guallar from the Welch Center for Prevention,
Epidemiology, and Clinical Research in Baltimore, and
colleagues measured chromium levels in 684 men who survived a
heart attack and in a similar number of men who’d never
experienced one. Chromium was measured in toenail clippings
because this provides a better indication of levels on a
long-term basis compared with measurement of blood levels.

Chromium levels were lower among older individuals,
declining about 9 percent with each decade increase of age, the
investigators report. Levels were also lower in those with high
blood pressure.

Chromium levels were also 13-percent lower in heart attack
patients than in comparison subjects, the researchers note.
Further analysis showed that subjects with the highest levels
were 35-percent less likely to have a heart attack than those
with the lowest levels.

“Although there are no national survey data on chromium
intakes, a study of self-selected diets of US adults indicated
that the chromium intake of a substantial proportion of
subjects may be well below” the levels that are considered
adequate, the researchers point out.

However, “considerably more evidence” is needed to
substantiate claims that chromium supplementation will improve
sugar control, weight loss, exercise capacity, and longevity,
the team says, “as well as to show the long-term safety of
chromium supplementation in humans.”

SOURCE: American Journal of Epidemiology, July 15, 2005.