7-Keto, a molecule that occurs naturally in the body and declines with age, increased the body’s ability to burn calories in dieting men and women, in one study.
Researchers recruited 10 men and 30 women, average age 38.5, who had an average body mass index of 32 (obese) and maintained a diet with 800 fewer calories than his or her daily energy requirement, estimated by the doctors. The double-blind study included three seven-day phases during which participants took 7-Keto, 7-Keto plus other nutrients or a placebo. Between each phase, participants took no supplements for seven days, for a total study period of five weeks.
At the start of the study and after each phase, scientists measured the resting metabolic rate, the rate at which the body burns calories while at rest. The resting metabolic rate naturally declines when the body takes in fewer calories in order to preserve energy, which can make losing weight more difficult for dieters.
The 7-Keto dose included 50 mg of 7-Keto plus 450 mg of rice powder per day. The 7-Keto combination included 50 mg of 7-Keto, 250 mg of calcium citrate, 150 mg of green tea extract standardized to include 50% epigallocatechin gallate (EGCG), the active ingredient in green tea, 50 mg of ascorbic acid, 100 mg of chromium nicotinate, and 2.5 mg of vitamin D3 per day. The placebo contained 500 mg of rice powder per day.
Compared to the start of the study, resting metabolic rate decreased 3.9% during the placebo treatment phase, resting metabolic rate increased 1.4% during the 7-Keto phase and resting metabolic rate increased 3.4% during the 7-Keto combination phase. Doctors believe that 7-Keto raises body temperature and stimulates fat-burning enzymes, but does not raise heart rate, a common side effect of prescription diet drugs. There were no reported side effects.