Randomized, double-blind, placebo-controlled, linear dose, crossover study to evaluate the efficacy and safety of a green coffee bean extract in overweight subjects

Abstract

Joe A Vinson1, Bryan R Burnham3, Mysore V Nagendran31Chemistry Department, 2Psychology Department, University of Scranton, Scranton, PA, USA; 3Health Sciences Clinic, Bangalore, IndiaBackground: Adult weight gain and obesity have become worldwide problems. Issues of cost and potential side effects of prescription weight loss drugs have led overweight and obese adults to try nutraceuticals that may aid weight loss. One promising nutraceutical is green coffee extract, which contains high concentrations of chlorogenic acids hat are known to have health benefits and to influence glucose and fat metabolism. A 22-week crossover study was conducted to examine the efficacy and safety of a commercial green coffee extract product GCA™ at reducing weight and body mass in 16 overweight adults.Methods: Subjects received high-dose GCA (1050 mg), low-dose GCA (700 mg), or placebo in separate six-week treatment periods followed by two-week washout periods to reduce any influence of preceding treatment. Treatments were counterbalanced between subjects. Primary measurements were body weight, body mass index, and percent body fat. Heart rate and blood pressure were also measured.Results: Significant reductions were observed in body weight (-8.04 ± 2.31 kg), body mass index (-2.92 ± 0.85 kg/m2), and percent body fat (-4.44% ± 2.00%), as well as a small decrease in heart rate (-2.56 ± 2.85 beats per minute), but with no significant changes to diet over the course of the study. Importantly, the decreases occurred when subjects were taking GCA. Body mass index for six subjects shifted from preobesity to the normal weight range (<25.00 kg/m2).Conclusion: The results are consistent with human and animal studies and a meta-analysis of the efficacy of green coffee extract in weight loss. The results suggest that GCA may be an effective nutraceutical in reducing weight in preobese adults, and may be an inexpensive means of preventing obesity in overweight adults.Keywords: green coffee bean extract, chlorogenic acid, body mass index, weight loss, body fat mass, blood pressure, heart rate