05 September 2009

Chromium nicotinate, but not picolinate may improve body composition

Advertisements that suggest chromium picolinate may help consumers lose fat or gain muscle mass are largely overstated.

A double-blind, randomized, placebo-controlled 12-week trial in 2001 found that chromium picolinate offered moderately obese women participating in an exercise program no significant changes to body composition, resting metabolic rate, plasma glucose, serum insulin, plasma glucagon, serum C-peptide or serum lipid concentrations (1).

The 2001 study’s results supported at least three previous studies of which had also shown that chromium picolinate had been ineffective in changing body composition in obese women, in military personnel and in weight-lifting football players (2-4).

A 12-week randomized, placebo-controlled trial in 2008 combined chromium picolinate with conjugated linoleic acid and evaluated effects on body composition changes of young, overweight women for 12 weeks (5).; still, no significant changes were found (5).

Lastly, because of chromium’s known effects on enhancing insulin signaling and glucose uptake, a randomized, placebo-controlled clinical trial in 2006 investigated effects of chromium picolinate on glycogen synthesis on overweight men after intense exercise (cycling) and high-carbohydrate feeding (6). Chromium picolinate did not appear to augment glycogen synthesis, but did appear to lower activity of phosphoinositol-3-kinase, an enzyme involved in regulating glucose uptake (6).

Chromium nicotinate, however, does appear to have effects on body composition.

One study on young, obese women who were given either chromium picolinate or chromium nicotinate found that chromium picolinate while "resulted" in weight gain for subjects, it also found that chromium nicotinate, when combined with exercise, did produce weight loss and lower insulin response (2).

Another randomized, double-blinded, placebo-controlled, crossover study on African American women gave 200mcg chromium nicotinate for over 2 months (2). The study did find significant fat loss and "sparing of muscle" in the women taking chromium nicotinate when combined with moderate exercise (7).

Reference List

1. Volpe SL, Huang HW, Larpadisorn K, Lesser II. Effect of chromium supplementation and exercise on body composition, resting metabolic rate and selected biochemical parameters in moderately obese women following an exercise program. J Am Coll Nutr 2001;20:293-306.
2. Grant KE, Chandler RM, Castle AL, Ivy JL. Chromium and exercise training: effect on obese women. Med Sci Sports Exerc 1997;29:992-8.
3. Trent LK, Thieding-Cancel D. Effects of chromium picolinate on body composition. J Sports Med Phys Fitness 1995;35:273-80.
4. Clancy SP, Clarkson PM, DeCheke ME et al. Effects of chromium picolinate supplementation on body composition, strength, and urinary chromium loss in football players. Int J Sport Nutr 1994;4:142-53.
5. Diaz ML, Watkins BA, Li Y, Anderson RA, Campbell WW. Chromium picolinate and conjugated linoleic acid do not synergistically influence diet- and exercise-induced changes in body composition and health indexes in overweight women. J Nutr Biochem 2008;19:61-8.
6. Volek JS, Silvestre R, Kirwan JP et al. Effects of chromium supplementation on glycogen synthesis after high-intensity exercise. Med Sci Sports Exerc 2006;38:2102-9.
7. Crawford V, Scheckenbach R, Preuss HG. Effects of niacin-bound chromium supplementation on body composition in overweight African-American women. Diabetes Obes Metab 1999;1:331-7.

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