posted July 19, 2000 10:35 PM         

The effects of pyruvate supplementation on body composition in overweight individuals.

A 6-wk, double-blinded, placebo-controlled study was done to ascertain the effects of pyruvate supplementation (6 GRAMS/d) on body weight, body composition, and vigor and fatigue levels in healthy overweight Caucasian men and women. Twenty-six individuals were randomly assigned to a placebo group (seven men, seven women) and a pyruvate-supplemented group (three men, nine women). In addition, all subjects participated in a 3 d/wk exercise program, which consisted of a 45-60 min aerobic/anaerobic routine. After 6 wk of treatment, there was a statistically significant decrease in body weight (-1.2 kg, P<0.001), body fat (-2.5 kg, P<0.001), and percent body fat (23.0% pre versus 20.3% 6 wk post) in the pyruvate group. Furthermore, Profile of Mood States fatigue and vigor scores improved significantly for the pyruvate group (P<0.05) at 6 wk (vigor) and 4 and 6 wk (fatigue). There was no significant change in total lean body mass in the pyruvate group. The placebo group demonstrated a significant increase (P<0.05) for POMS vigor at 2 and 4 wk with no changes occurring in any of the remaining parameters measured. Thus, the ingestion of 6 GRAMS of pyruvate for 6 wk, in conjunction with mild physical activity, resulted in a significant decrease in body weight and fat mass.

Pyruvate Modifies Body Fat to Muscle Mass Ratio

Researchers led by D. Kalman, M.D., at Beth Israel Medical Center in New York
divided 53 male and female subjects into three groups. The pyruvate group
received capsules that provided 6 g pyruvate and 250 mcg chromium per day; the
placebo group, capsules containing maltodextrin; and the control group, no
capsules. Throughout the six-week study, all three groups ate the same
2,000-calorie-per-day diet and followed the same 30-minute routine of aerobic and
anaerobic exercise five days a week.

By the end of this period, researchers found no significant change in body weight in
any of the three groups. However, body composition (the ratio of body fat to lean
body mass) differed markedly among the groups. Participants ingesting the
pyruvate lost an average of 4.8 pounds of body fat, a loss equivalent to 12.4
percent of their original body fat. In comparison, subjects in the control group
gained 0.1 pound of body fat on average, and subjects in the placebo group lost an
average of 0.2 pound of body fat. The treatment group's fat loss is significant
considering the study participants ingested 2,000 calories a day. In earlier pyruvate
studies subjects ate only 500 or 1,000 calories daily.

How did the pyruvate group lose 4.8 pounds of fat without a significant change in
body weight? Because they also gained an average of 3.4 pounds of muscle. The
control group gained only 0.4 pound of muscle, and the placebo group lost 0.3
pound of muscle. The pyruvate group's gain in muscle mass is impressive
considering participants did not engage in any heavy weight training but only
performed light exercises.