Metal Information Center

Chromium - includes related articles on chromium picolinate and recommended daily amounts

October 10, 2007 – 7:02 am

Lose The Fat; Keep The Muscle,” says the ad for chromium picolinate.”Rake in the Profits,” is more like it.

There’s no good evidence that chromium–picolinate or any other kind–helps people lose fat or build muscle. But for the millions of Americans who are on their way to diabetes, extra chromium could hold out a glimmer of hope.

GLUCOSE INTOLERANCE

“Chromium helps insulin transfer glucose and other nutrients from the bloodstream into cells,” says Richard Anderson, a chromium expert at the U.S. Department of Agriculture.

And that’s important. If glucose (blood sugar) doesn’t move easily into your cells after a meal, your blood sugar level takes longer to return to normal. And if it stays high enough long enough, the diagnosis can change from “glucose intolerance” to “diabetes.”

“We might be able to prevent many people from developing diabetes as they get older by doing something about their glucose intolerance earlier,” says Anderson. That something, he suspects, may have to do with chromium.

In several studies, when he gave glucose-intolerant people 200 micrograms (mcg) of chromium a day, they were better able to remove excess glucose from their blood after meals than glucose-intolerant people who took a (lookalike but inactive) placebo.(1)

But there’s a catch. “I think that chromium only works for people who aren’t getting enough from their diets,” says Anderson.

Unfortunately, it’s next to impossible to figure out who’s getting enough and who isn’t. The only way to tell is to give people chromium and see if their glucose tolerance improves. If it does, then they probably were deficient.

Even in those cases, though, chromium is far from a cure for glucose intolerance. The modest declines in blood sugar levels that Anderson saw, for example, weren’t enough to bring them down to normal. What’s more, none of his studies lasted more than three months, so we don’t know for how long chromium keeps working.

And what about people who already have diabetes? Could taking chromium help keep their blood sugar in check?

So far, a handful of studies have come up empty.(2) Anderson contends that’s because diabetics need much higher doses than 200 mcg a day. He says that his latest study, of diabetics in China, shows that 1,000 mcg a day helps lower blood sugar. His results haven’t yet been published.

BUILDING MUSCLE

Chromium’s potential to lower blood sugar could be important but that’s not what attracts most people to the mineral, particularly to chromium picolinate–a patented formula marketed by Nutrition 21 of San Diego (see “In a Picolinate”). What rings up sales is the lure of losing fat and gaining muscle tone effortlessly.

But what would happen to those sales if shoppers knew that chromium picolinate’s claims are all based on just three small published studies that used crude measurements? Or that those results have never been duplicated using more-reliable methods?

The studies were carried out by biochemist Gary Evans at Bemidji State University in Minnesota. Evans is now a consultant to the chromium industry. In the largest of the three, he gave 16 students a daily dose of 200 mcg of chromium and 15 students a placebo. After six weeks, those who took the chromium had added six pounds of muscle and lost seven pounds of fat.(3)

“Changes like that in such a short period of time are preposterous, as anyone familiar with training effects knows,” says Robert Lefavi, who studies the mineral requirements of athletes at Armstrong State College in Savannah, Georgia. “You can’t even get results like that using anabolic steroids.”

The trouble was that Evans measured changes in fat by pinching the folds of fat beneath the students’ skin using hand-held calipers–an inexact method. Since then, scientists using more-precise tools have seen little or no difference between chromium-takers and non-takers.

“When we used underwater weighing, which accurately measures body fat, we found that 200 mcg a day for eight weeks had no effect on the muscle, fat, or strength of football players,” reports Priscilla Clarkson, a sports nutrition expert at the University of Massachusetts in Amherst.(4) Other studies using 160 to 400 mcg of chromium a day showed no effect on fat or muscle in men and women weightlifters in Louisiana, sedentary university students in Maryland, or men in a physical training program in North Dakota.(5-7) And it didn’t help overweight Navy personnel in San Diego lose weight.(8)

“These latest studies should put to rest the notion that chromium is a shortcut to losing fat or building muscle tone,” concludes Henry Lukaski, a mineral researcher at the USDA’s Nutrition Center in Grand Forks, North Dakota.

OTHER CLAIMS

* Chromium lowers cholesterol. There is some evidence in animals that chromium affects cholesterol levels. So could taking chromium reduce your risk of heart disease?

“The results are inconclusive,” says researcher Robert Lefavi. A few small studies did show that 200 to 600 mcg of chromium a day for two to 16 months raised HDL (”good”) cholesterol by anywhere from 11 to 25 percent.(9) But other, similar studies have come up empty.(10)