From
chromiuminfo.org
Chromium May
Reduce Diabetes Risk
Washington. DC
(November 1, 1997)- Chromium supplements appear beneficial
in the treatment of type II diabetes, suggest the results
of a placebo-controlled clinical trial conducted in China.
The final results of a study appear in the current issue of
the medical journal Diabetes.
The USDA sponsored
study was designed to determine whether supplemental chromium
could help in the control of type II (non-insulin dependent)
diabetes. One-hundred and eighty men and women in China who
were already being treated for type II diabetes received either
placebo, 100 mcg (micrograms) of chromium two times per day,
or 500 mcg of chromium two times per day. The volunteers continued
to take their normal medications and were asked not to change
their normal eating and living habits.
Glycosylated hemoglobin
(HbA1c) values improved significantly after 2 months in the
group receiving 1,000 mcg/day of chromium. The test is a measure
of how well glucose is metabolized, and is considered a gold
standard in medicine. These values were lower in both chromium
groups after 4 months. Fasting glucose levels were lower in
the high-dose group after 2 and 4 months. Two-hour glucose
values were also significantly lower for the high dose chromium
group after both 2 and 4 months. In addition, fasting and
two-hour insulin values decreased significantly in both groups
receiving supplemental chromium after 2 and 4 months. Moreover,
plasma total cholesterol also decreased after 4 months in
the subjects receiving the high dose of chromium.
"These data demonstrate
that supplemental chromium had significant beneficial effects
on HbA1c, glucose, insulin, and cholesterol variables in subjects
with type 2 diabetes. The beneficial effects of chromium in
individuals with diabetes were observed at levels higher than
the upper limit of the Estimated Safe and Adequate Daily Dietary
Intake," the researchers note.
Both the high-
and low-dose chromium groups had a significant drop in plasma
insulin just two months after beginning the supplements and
a further drop at four months. People with type II, or maturity-onset,
diabetes produce more insulin than normal in the early stages
of the disease, because the insulin is less efficient at clearing
glucose from the blood. Chromium apparently makes the hormone
more efficient.
The study was a
collaboration between USDA investigator Dr. Richard Anderson
and Dr. Nanzheng Cheng. Cheng--a former visiting scientist
in Anderson's laboratory--and her sister Nanping Cheng, a
physician in Beijing. The study participants were recruited
at three Beijing hospitals.
In the U.S., it's
possible that people with diabetes would need higher levels
of chromium to realize similar improvements because Americans
are larger than the Chinese and eat more fat and sugar. All
of these factors raise the requirement for chromium. No other
studies have seen consistent improvements with 200 mcg.
Anderson also said
he has maintained rats on daily doses of chromium picolinate
or an inorganic form of the mineral several thousand times
above the highest suggested intake for humans with no adverse
effects on the sensitive organs.
There is no Recommended
Dietary Allowance for chromium. The estimated safe and adequate
dietary intake is between 50 and 200 mcg daily. Most Americans
consume less than 50 mcg, Anderson said. He has analyzed well-balanced
diets prepared by dietitians and found them to contain only
about 33 mcg per day.
The study results
appear in Diabetes, November 1997, Volume 46, Number 11
