Chromium

Tagged:  

"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? 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.[a]

"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 weight lifters 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.(TM)

• Chromium helps you live longer. One theory blames aging on the gradual damage that proteins suffer when they're exposed to glucose in the blood. Chromium appears to help keep glucose levels under control. Does that mean it can slow down the aging process?

It did for a handful of rodents in a pilot study, which is the only published research on chromium and aging. Ten rats that were fed extra chromium picolinate throughout their lives lived 25 percent longer than 20 rats that were fed different forms of chromium.(11)

Unfortunately, the study couldn't role out the possibility that something other than the chromium picolinate made the rats live longer.

"The results are tantalizing, but not very convincing," says Richard Weindruch, a lifespan researcher at the University of Wisconsin in Madison.

1. Metabolism 32: 894, 1983.
2. Diabetes Care 6: 319, 1983.
3. Int'l Journal of Biosocial and Medical Research 11: 163, 1989.
4. Int'l J. of Sport Nutrition 4: 142, 1994.
5. Int'l J. of Sport Nutrition 2: 343, 1992.
6. Medicine and Science in Sports and Exercise 28: 139, 1996.
7. Amer. J. of Clinical Nutrition, in press.
8. Journal of Sports Medicine and Physical Fitness, in press.
9. Metabolism 41: 768, 1992.
10. Journal of Nutrition 123: 626, 1993.
11. Ady. in Scientific Research 1: 19, 1994.

PHOTO (COLOR): Taking chromium won't help you lose fat or build muscle.
In a Picolinate

What a business.

"A few dollars worth of chromium would supply the whole country," says USDA researcher Richard Anderson with only a little exaggeration.

So what's so special about the more-expensive, patented chromium picolinate [pick-oh-LIN-ate] that's made by Nutrition 21 of San Diego? Or the pricey Chrome Mate brand of chromium polynicotinate [poly-nick-oh-TIN-ate] that's sold by Inter Health of Concord, California?

Both take the ordinary kind of chromium that's found in food and most supplements and bind it to special molecules. That makes it more easily absorbed, the manufacturers claim.

But does it make their chromium better than the ordinary kind? No.

Although both companies talk a good game, neither can point to even one well-designed, published study in humans that shows that its formulation works better than regular chromium.
Getting Enough?

If you're a typical American, you probably consume between 25 and 35 micrograms (mcg) of chromium a day. The Estimated Safe and Adequate Daily Dietary Intake--which experts use when they don't have enough information to set a Recommended Dietary Allowance (RDA)--is 50 to 200 mcg. But getting less than that isn't necessarily bad.

"There's been a long debate over whether we have enough good information about chromium needs to even set a specific range of intake," says Xavier Pi-Sunyer of the Nutrition Research Center at St. Luke's-Roosevelt Hospital Center in New York. "Nobody knows what the numbers should be. It's pretty arbitrary."

Complicating the picture, says Pi-Sunyer, is that "there's probably a reservoir of extra chromium in the body, although it's unclear where."

We also pick up the mineral from the air and the water supply. "It's everywhere," he says. "There's even chromium in canned foods, because it leaches out of stainless steel cans." And, if you're deficient, your body absorbs more of the chromium you take in, he adds.

The bottom line: While most people probably get enough chromium, it wouldn't hurt to take a multi-vitamin-and-mineral supplement that contains at least 25 mcg.
THE BOTTOM LINE

* Chromium won't help you lose weight or build muscle.
* if you're glucose-intolerant and not getting enough chromium from your diet, taking 200 mcg a day may help lower your blood sugar.
* Don't waste your money on designer formulations like chromium picolinate or chromium polynicotinate. They're no better than the ordinary chromium that's found in foods and most supplements.
* The best sources of chromium are whole grains, fruits, and vegetables.

~~~~~~~~

By DAVID SCHARDT

Share this with your friends