Effects of Oligonol^® Supplementation on Abdominal Fat in Japanese Overweight Volunteers: A Randomized, Double-Blind, Placebo-Controlled, Parallel Group Study

Obesity is known to induce diabetes, hypertension, and dyslipidemia, and reducing obesity is important from the perspective of disease prevention. Oligonol, a standardized oligomerized-polyphenol from Litchi chinensis fruit extract, is expected to have high absorption and body fat reduction. In this study, the effects of Oligonol intake on abdominal fat were examined in overweight Japanese participants. This randomized, double-blind, placebo-controlled trial was performed including 66 overweight adult men and women (body mass index [BMI] of 25 or more and less than 30 kg/m²) who were assigned to receive a daily dose of placebo or 200 mg Oligonol (40 mg as monomers and dimers of flavanols from lychee and tea) for 12 wk. The primary endpoint was a reduction of the visceral fat area (VFA) as quantified by computed tomography scanning after continual intake of test foods for 12 wk. In addition, body weight, BMI, waist circumference, peripheral blood tests, and general urinalysis were performed. Of 66 participants (33 per group), 63 were included in the efficacy analysis (placebo n=32; Oligonol n=31). Intake of 200 mg Oligonol significantly reduced abdominal VFA compared with the placebo group. No clinically relevant adverse events related to the intake of Oligonol were observed. These results indicate that Oligonol had the abdominal visceral fat reduction effect in overweight participants.