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Assessing the risks
Since chromium tests are hard to administer and interpret, some nutritional experts prefer to talk about an individual's risk of developing a chromium deficiency, which is said to increase if a person:
1) Has a diet which is high in simple sugars (such diets tend to increase urinary chromium excretion, sometimes by as much as 300 per cent!),
2) Eats fairly large quantities of 'refined' foods, especially those which contain lots of white flour and sugar (such foods have a low chromium content),
3) Has high blood-insulin levels, which increase chromium requirements, and/or
4) Exercises intensely fairly frequently, which roughly doubles chromium excretion..

Trouble is, that's not a very precise way of reckoning whether you need more chromium. In addition, you could get around risk factors no. 1 and 2 by making some simple changes in your diet, rather than taking chromium supplements. So, let's take a closer look at the actual scientific research on chromium supplementation. Is there any solid reason to think that chromium could be helpful to athletes?
Evans' work (mentioned above) linking chromium with body-composition improvements in football players came in for criticism from other scientists, with one of the biggest carps being that Evans did not control for potential steroid use by his athletes. However, Evans has ridiculed the notion that his players were 'juiced' on anabolic chemicals. 'Bemidji State is hardly a breeding ground for the National Football League,' notes the researcher. 'The school is in the hinterland of northern Minnesota, where drug abuse is about as common as mild winter weather. Plus, critics of the research can't explain why only the chromium-supplemented athletes would have been using steroids, while placebo-group individuals were keeping themselves clean,' Evans adds..

Evans, an inorganic chemist who has recently published a book entitled Chromium Picolinate: Everything You Need to Know, has also published his research in some rather obscure scientific journals - or not at all. One reason for this is that he did not use the most widely accepted technique dual x-ray absorptiometry (DEXA) - to measure body composition, causing some scientists to question whether his results were meaningful (and making it hard for Evans to get his studies into mainstream journals)..

Although Evans' methodology has been questioned, no one can fault him for lack of energy and enthusiasm - or for not making an effort to understand the full effects of chromium within the human body. In one unpublished study, Evans found that male athletes increased lean mass while taking in 400 daily mcg of chromium. An especially interesting aspect of this third study was that Evans was able to link chromium supplementation with higher DHEA concentrations and lower insulin levels..

The DHEA connection is an interesting one. DHEA is a steroid hormone, manufactured in the adrenal glands of both males and females, which seems to serve as a 'back-up' sex hormone. In females, the DHEA can be converted to oestrogen, assisting in bone building and other essential activities. In males, DHEA can be transformed into testosterone, a potent builder of muscle and connective tissue. Overall, DHEA has anabolic effects similar to those claimed for chromium picolinate..

However, the key aspect of this story is that higher insulin levels seem to lead to lower DHEA concentrations, while reduced insulin permits greater DHEA. Since chromium enhances the potency of insulin, it allows the body to get by with a lowered insulin output. 'The consequent upswing in DHEA may be one reason why chromium supplementation enhances muscle mass so well,' contends Evans..


In support of Evans
But does chromium really enhance muscle mass? Up until now, we basically had Evans' much-criticised research and swine studies to support this hypothesis. However, a very recent study, using a higher-than-usual dose of chromium given over a longer-than-normal time period, supports the idea that chromium can boost muscle tissue. In this research, carried out at Wright State University in Dayton, Ohio, 40 collegiate swimmers were divided into two groups, with one group (10 males and 10 females) ingesting 400 mcg of chromium picolinate per day for 24 weeks and the other group (also 10 males and 10 females) following a normal, non-supplemented diet. The two groups trained in identical fashion..

After 24 weeks, the chromium-rich swimmers had increased lean mass by 3.3 per cent and decreased per cent body fat by 6.4 per cent, compared to the placebo swimmers. The improvement was actually greatest in the chromium-supplementing female swimmers, who carved body fat by over 8 per cent. Anecdotally, chromium swimmers tended to report more performance improvements and less muscle soreness, compared to non-supplemented athletes ('Chromium Picolinate Supplementation in Male and Female Swimmers,' Medicine and Science in Sports and Exercise, vol. 28(5), p. S111, Abstract no. 664, 1996)..

Why did the Wright State study find key benefits associated with chromium supplementation, while several other studies have detected little positive effect? Dr. D. Drew Pringle, one of the Wright State researchers, contends that the higher dosage of chromium (400 mcg rather than the usual 200) and longer time period of the study (24 weeks instead of eight to 12 weeks) were key reasons for the difference. 'The greatest rate of change in body composition didn't take place until after 12 weeks of supplementation,' says Pringle. Unfortunately, Pringle's group used underwater weighing to assess body-composition changes, a method which is considered less reliable than DEXA..

Some athletes swear by it. Anecdotally, chromium's popularity with athletes seems to indicate that it must be having some kind of effect. After all, many athletes swear that their performances have improved post-chromium-supplementation, and many individuals who are trying to shed pounds say that 'nothing worked' until they tried chromium. Of course, the placebo effect may be at work here, but another point to consider is that many 'chromium supplements' are actually not pure chromium picolinate but combinations of chromium with some pretty potent other stuff. In fact, one of the most popular chromium supplements sold in health-food stores and nutrition shops actually contains chromium and a very potent herbal extract called 'Ma Huang'..

Ma Huang is actually a powerful stimulant, known to boost metabolism, step up heart rate, heighten alertness, and - possibly - increase muscular strength. Its key ingredient is ephedrine, a chemical which is banned from the competitive stage by both the NCAA and the IOC. In a variety of different studies, ephedrine has been linked with increased weight loss and improvements in body composition (see, for example, "The Effect of Ephedrine/Caffeine Mixture on Energy Expenditure and Body Composition in Obese Women," Metabolism, vol. 41(7), pp. 686-688, 1992). This of course raises the possibility that the key ingredient in the 'chromium supplements' which are so popular with athletes and weight-reduction people may in fact not be chromium but Ma Huang..

So, what's the bottom line on chromium? The recommended 'safe and adequate intake' for chromium has been set at 50 to 200 mcg per day by the Recommended Dietary Allowance Committee of the National Research Council in the United States, but research suggests that about 90 per cent of the population in the U.S. and Britain consume less than 50 micrograms daily ('Chromium Intake, Absorption, and Excretion of Subjects Consuming Self-Selected Diets,' American Journal of Clinical Nutrition, vol. 41, pp. 1177-1183, 1985). 'Our studies suggest that many athletes are only taking in 30 to 35 mcg daily, so it's not too unreasonable to say that these people should consider taking in more chromium,' notes Marc Rogers, Ph.D., a former St. Louis Marathon winner who is currently an exercise physiologist at the University of Maryland..

Rogers is actually one of the researchers who found no upswings in muscle or downturns in fat associated with 200 mcg of daily chromium. 'It is possible that there's a threshold effect at work here,' says Rogers. 'Maybe you do have to take at least 400 mcg of the stuff over a fairly long period to get a benefit.'
Many nutritional experts have contended that one shouldn't exceed a daily dose of 200 mcg in order to avoid the possibility of chromium toxicity. However, those fears seem to be fading. Chromium expert Richard Anderson (principal investigator in the four-month Chinese study using 1000 mcg per day) says you can take much higher amounts without risk. He believes that extra chromium simply passes out of the body in urine, an event confirmed by the Massachusetts research mentioned earlier. Pringle found no problems with intakes of 400 mcg daily in his half-year study, and a current investigation carried out with humans at Penn State University is actually using 900 mcg of daily chromium. The latter study is being carried out by esteemed researchers Wayne Campbell and Bill Evans with a group of male strength trainers aged 50 to 75, many of whom are overweight. 'This is precisely the kind of group with people who tend to have higher insulin and blood-sugar levels - in which we'd expect to see a positive effect from chromium,' says Campbell..


Common sense about chromium
Campbell has no major problem with people taking chromium supplements in reasonable quantities but contends that athletes should remember that chromium is no magical elixir. 'You'll get a much greater improvement in muscle mass from an excellently conducted strength-training programme than you will from taking chromium supplements, ' says Campbell. 'And if you want to lose weight, you'll be be far better off focussing on reducing caloric intake and increasing exercise levels, instead of relying on chromium.'
Richard Anderson, who spearheaded the Chinese study which linked chromium with benefits for Type II diabetics, says, 'It's a reasonable idea for athletes to take 200 micrograms of chromium daily, along with a balanced nutritional supplement which includes the other essential vitamins and minerals.' Anderson's statement seems quite sensible. At this point in time, PEAK PERFORMANCE can't recommend taking higher doses of chromium - at least not until another study demonstrating the benefits of such supplementation is carried out with humans. To verify the effects of chromium, this investigation should be one which uses DEXA, not underwater weighing, bioelectrical impedance, or skin callipers, to measure body composition..

Owen Anderson

Dangers Of Chromium Picolinate and Benefits

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