|Chromium is a metallic element that functions as a co-factor to augment the action of insulin, and thus influences carbohydrate, protein, and fat metabolism. When one looks at the store shelves, the main chromium supplement found is chromium picolinate. Picolinate is simply an organic ligand that enhances absorption of chromium from the digestive tract. In the past decade it was discovered that individuals with diabetes (type I, or type II) may experience improvements in insulin function and/or blood lipid profiles (i.e., cholesterol, HDL, etc.) when given chromium supplementation. This is especially true in those who are chromium deficient. These findings, of course, generated a lot of interest in the athletic community. Could chromium help someone build muscle or lose fat?
Initial research supported the assertion that chromium supplementation increased muscle mass and, not unexpectedly, this was enough to start a fad. However, this initial report has been criticized for methodology flaws, related to body composition testing, and subsequent research has not demonstrated an anabolic effect. These subsequent studies used more accurate body composition testing, hydrodensitometry and dual X-ray absorptiometry, and failed to demonstrate any increase in lean body mass (i.e., lower percentage body fat). All were doubled-blind, placebo controlled trials that -- in addition to body composition testing -- also evaluated muscular strength of the subjects before and after the supplementation period. There was agreement among these research groups that chromium supplementation failed to have any effect on strength or strength training.
Another potential role for chromium supplementation is in the realm of endurance exercise performance. Certainly, if chromium increased lean body mass then some athletes would experience benefit. Thus far there are no data that conclusively support this. With respect to recovery there are more questions than answers. Is it possible that chromium supplementation could assist muscle and liver glycogen "rebuilding" post exercise? Could prolonged supplementation (e.g., years) help an athlete perform better? At this point in time, no one knows. Clearly more information done in a controlled, scientific method is needed.
A final consideration is safety. The U.S. recommended daily dietary allowance has not been firmly established, but many experts feel that 50 200 micrograms per day is appropriate. Virtually all of the commonly available daily vitamin supplements contain chromium (e.g., Centrum contains 65 micrograms per tablet). Although reportedly safe in the amounts commonly taken there are indications of toxicity (e.g., anemia, nephrotoxicity) with respect to prolonged, excessive use. There is a case report of suspected chromium picolinate induced rhabdomyolysis (massive muscle breakdown) that occurred in a 24 yr. old women body builder who took 1200 micrograms over a 48 hour period.
Currently, the best advice is to approach the issue of chromium supplementation with caution. You are encouraged to consult with your doctor regarding chromium, but especially if you have with diabetes, and/or high cholesterol/ triglycerides. Never forget that the diet and dietary supplement business is a multi-billion dollar behemoth. Whats hot for a few years quickly fades, only to be replaced by another "new" miracle cure. Just witness what has occurred with the "Zone" diet (i.e., 40/30/30): It has now been fairly conclusively proven to have either no effect, or to be ergolytic (energy robbing) for athletes. Thus, this years hot potato is often next years, "dud spud".
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