Objective: To evaluate the effect of a dietary supplement containing herbal caffeine (70 mg/dose) and ephedra (24 mg/dose; C&E) on metabolic rate, weight loss, body composition, and safety parameters.
Research methods and procedures: In phase I, 12 healthy subjects with a BMI of 25 to 35 kg/m2 had resting metabolic rate (RMR) measured for 2 hours after ingesting C&E or a placebo on two occasions 1 week apart, followed by a 1-week washout before phase II. In phase II, these 12 and 28 additional subjects were randomized to a 12-week, double-blind trial comparing C&E (3 times/day) to placebo. In phase III, the C&E group was given open-label C&E for 3 months, and the placebo group was given C&E for 6 months.
Results: In phase I, C&E gave an average 8 +/- 0.1% (SE) rise in RMR over 2 hours compared with placebo (p < 0.01). In phase II, weight loss at 12 weeks was 3.5 +/- 0.6 kg with C&E compared with 0.8 +/- 0.5 kg with placebo (p < 0.02). The percentage fat lost, shown by DXA, was 7.9 +/- 2.9% with C&E and 1.9 +/- 1.1% with placebo (p < 0.05). Pulse decreased more in the placebo group that in the C&E group (p < 0.03). There were no differences in lipid levels or blood pressure. In phase III, there was a 6-month loss of 7.3% and 7.8% of initial body weight for the groups on placebo and C&E during phase II, respectively. There were no serious adverse events.
Discussion: C&E increased RMR significantly by 8% compared with placebo, promoted more weight and fat loss than placebo, and was well tolerated.
Copyright 2004 NAASO