If you've heard of “chromium picolinate”, you have probably also heard of the many benefits it's purported to have – from helping to reduce body fat to increasing lean muscle and enhancing insulin sensitivity (which helps your body burn fat).
But according to a number of studies, chromium picolinate is not delivering on the promise it once held. And in fact, their may be reason to avoid it altogether...
Chromium is an essential nutrient (meaning your body does not manufacture it, so you need to take it in through dietary sources). It's key role within your body is to help metabolise carbohydrates and lipids (fats) for energy production.
Chromium picolinate is the best known form of chromium supplement, but there are others (including chromium chloride and chromium polynicotinate). What makes chromium picolinate unique is that it increases cellular absorption of chromium ten times as much as chromium alone.
The first claims about the benefits of chromium picolinate stem from research done by Nutritional Consultant Gary Evans in the 1980s who claimed that it could help to both increase muscle mass and reduce body fat stores . Since that time there have been numerous studies aimed at proving or disproving the efficacy of chromium picolinate.
One aspect of weight control that is receiving a lot of attention is insulin sensitivity. Insulin is key to weight control in several ways:
In other words, the more insulin our bodies need to secrete in order to transport nutrients into our cells, the greater the negative impact it should have on weight loss and body fat levels. Conversely, if our bodies are sensitive to insulin, less of it needs to be secreted and this will be more favourable for maintaining low body fat levels.
Generally as we age, our bodies become less sensitive to insulin so if chromium (or chromium picolinate) can play a role in increasing your body's sensitivity to insulin, in theory it can help to keep body levels in check.
A analysis compiled by the National Institute of Health combined the results of a number of studies completed on chromium where the average amount of supplement tested was 200 micrograms or less. They concluded that chromium supplements have no effect on glucose or insulin concentrations in non-diabetic subjects.
A team of researchers, from the University of San Diego, measured the affects of chromium picolinate on insulin sensitivity, serum lipids, and body composition in healthy, older men and women. Test subjects were randomly divided between a placebo group and a chromium picolinate group – with the test group being given 1000 micrograms of chromium picolinate. Researchers concluded that “no significant change in serum lipids, insulin sensitivity, or body composition was observed in the chromium group compared with the placebo group.”
While it may be of some use, alongside other forms of treatment, in conditions such as type 2 diabetes and hyperglycaemia [5,9], it seems that in normal weight, non-diabetics chromium picolinate has little effect on insulin sensitivity.
Of course, just because chromium picolinate doesn't effect insulin levels doesn't rule it out as a fat loss aid.
Claims of reduced body fat and increased lean muscle were put to the test by the U.S. Department of Agriculture in 1996.</p> In their study, researchers from the US Department of Agriculture supplemented the subjects' weight training regime with 200 micrograms of chromium daily over a 12-week period. They reported that "chromium supplementation, in conjunction with a progressive, resistive exercise training program, <strong>does not</strong> promote a significant increase in strength and lean body mass, or a significant decrease in percent body fat.”
The Naval Research Center took their study a step closer to Evans's study, when they tested the effects of chromium picolinate (rather than chromium alone in the study above). Their group of overweight test subjects were divided into two smaller groups – one receiving 400 micrograms of chromium picolinate and the other a placebo. At the end of 16 weeks, NRC researchers reported, both groups had lost weight. However, the chromium group failed to show a significantly greater reduction in either percent body fat or body weight, or a greater increase in lean body mass, than did the placebo group.
Of grave concern is a study published by The FASEB Journal in 1995. It found that chromium picolinate reacting with naturally occurring antioxidants inside cells can form a DNA-damaging variation of chromium. This reaction caused a 3 to 18-fold increase in chromosome damage among Chinese hamster ovary cells (a standard assay model for chromosome damage), and skeletal mutations in the offspring of pregnant mice.
It is important to note that in both these studies, the dosage given was 3000 times and 1000+ times greater (respectively) than those seen in humans taking 200 micrograms per day. Moreover, in 2004, the renowned Committee on Mutagenicity reviewed available research on chromium picolinate and determined that it was not mutagenic (DNA-damaging), and that there was no need to avoid it. This is now the official stance of the Food Standards Agency in the UK - that the balance of evidence shows that chromium picolinate is not harmful to humans in safe doses.
Still, researchers such as Henry Lukaski (of the Department of Agriculture study) and Dr. Diane Stearns (one of the authors of the study done on Chinese hamster ovaries) warn against long-term use or excessive doses of chromium picolinate.
To Sum Up...
For those looking for a boost or adjunct to their fat loss programme, chromium picolinate is not worth experimenting with according to the research. Chromium picolinate is considered safe and there is no need to avoid it. It may have some use in individuals who cannot regulate blood glucose levels adequately but this should only be as an adjunct to regular treatment and any benefits have yet to be confirmed.