What is Chromium Picolinate?
Chromium is an essential trace element that is involved in the metabolism of carbohydrates, lipids, and proteins mainly by increasing the efficiency of insulin.
Proposed Benefits of Chromium Picolinate
It is proposed that chromium plays a role in the maintenance of normal glucose tolerance, especially in individuals with diabetes.
Other purported benefits of chromium are to assist in weight loss and gains in muscle mass.
Mechanism of Action of Chromium Picolinate
It is suggested that the chromium intake of the general population is sub-optimal. However, there is no reliable determination of chromium status due of lack of reliable analytical methods and low concentrations of chromium in biological material. If intakes among some individuals are low it is postulated that supplementation may provide benefits.
The insulinogenic characteristic of chromium has prompted the hypothesis that chromium may have an anabolic function (i.e. increase muscle mass) (1). There are also claims that chromium picolinate may increase lean body mass and reduce body fat by increasing growth hormone levels.
It is also postulated that the insulinogenic effects of insulin may improve glucose tolerance in individuals with diabetes or insulin resistance.
Research on Chromium Picolinate
An initial study by Evans reported that young sedentary males and football player participating in resistance training and supplemented with 200mg of chromium per day (in the form of chromium picolinate) increased lean body mass and decreased fat mass compared with non-supplemented men who were also involved in resistance training (1). The effect on muscle strength was not reported. This study used skinfolds to measure body fat, which is not a reliable method for the estimation of body fat percentage
Further research which have used more reliable methods for measuring body composition or larger sample sizes have not been able to replicate these initial findings (2-8). While many of these studies showed improvements in body composition as a result of resistance training, they failed to show chromium-specific changes in body composition. In addition these studies have not shown increases in muscle strength (2,6,8).
It could be argued that in some of these studies no benefit from chromium was seen because the subjects were not chromium deficient due to their large energy intakes (3). In individuals with inadequate chromium intakes, more positive results may be apparent.
A recent meta-analysis which investigated the effects of supplements on lean mass and muscle strength found that chromium supplementation did not result in significant increases in muscle size or strength (9).
The claims that chromium picolinate increases growth hormone are not supported by biomedical literature.
A recent met-analysis on the glucose and insulin responses to chromium supplementation concluded that randomised clinical trials showed no benefits in non-diabetic subjects (10). It was concluded that the data for persons with diabetes is inconclusive and more trials are necessary. One larger Chinese study that measured long-term glucose control (by measurement of glycated haemoglobin levels) in diabetic individuals showed an improvement with chromium supplementation (11). Studies in other populations with diabetes are needed to confirm or refute this finding.
Rating of Efficacy for Chromium Picolinate
Most studies do not support the premise that supplementation with chromium picolinate increases lean body mass and decreases body fat. There is the possibility that those who are deficient in chromium may show more beneficial changes in body composition.
1. Evans G.W. The effect of chromium picolinate on insulin controlled parameters in humans. Int J Biosoc Med Res. 11:163-180, 1989.
2. Campbell W.W., Joseph L.J., Anderson R.A., Davey S.L., Hinton J. and Evans W.J. Effects of resistance training and chromium picolinate on body composition and skeletal muscle size in older women. Int J Sport Nutr Exerc Metab. 12:125-135, 2002.
3. Clancy S.P., Clarkson P.M., DeCheke M.E., Nosaka K., Freeson P.S., Cunningham J.J. and Valentine B. Effects of chromium picolinate supplementation on body composition, strength, and urinary chromium loss in football players. In J Sport Nutr. 4:142-153, 1994.
4. Hallmark M.A., Reynolds T.H., DeSouza C.A., Dotson C.O., Anderson R.A. and Rogers M.A. Effects of chromium and resistance training on muscle strength and body composition. Med Sci Sports Exerc. 28:139-144, 1996.
5. Hasten D.L., Rome E., Franks B.D. and Hegsted M. Effects of chromium picolinate on beginning weight training students. Int j Sports Nutr. 2:343-350, 1992.
6. Lukaski H.C., Bolonchuk W.W., Siders W.A. and Milne D.B. Chromium supplementation and resistance training: effects on body composition, strength, and trace element status of men. Am J Clin Nutr. 63:954-965, 1996.
7. Trent L.K. and Thieding-Cancel D. Effects of chromium picolinate on body composition. J Sports Med Phys Fitness. 35:273-280, 1995.
8. Walker L.S., Bemben M.G., Bemben D.A. and Knehans A.W. Chromium picolinate effects on body composition and muscular performance in wrestlers. Med Sci Sports Exerc. 30, 1998.
9. Nissen S.L. and Sharp R.L. Effect of dietary supplements on lean mass and strength gains with resistance exercise: a meta-analysis. J Appl Physiol. 94:651-659, 2002.
10. Althuis M.D., Jordon N.E., Ludington E.A. and Wittes J.T. Glucose and insulin responses to dietary chromium supplements: a meta-analysis. Am J Clin Nutr. 76:148-155, 2002.
11. Anderson R. Chromium, glucose intolerance and diabetes. J Am Coll Nutr. 17:548-555, 1998.