薬理と治療

Abstract

Objectives Hops are the main components of beer that provide flavor and bitterness. Iso-α-acids, the bitter components of hops, have been reported to reduce body fat in humans, but the bitterness induced by effective doses of iso- α-acids precludes their acceptance as a nutrient. The matured hop bitter acids （MHBA）of oxidized hops appear to have a more pleasant bitterness compared to the sharper bitterness of iso-α-acids. We evaluated the effect of the matured hop ethanol extract（MHE）, which contains MHBA, on the body fat reduction. Methods A double-blind, placebo-controlled parallel group study was conducted on healthy subjects aged 40 to below 65 years with a BMI of 25 to below 30 kg╱m2. Ninety- three volunteers were divided into three groups and daily ingested six capsules that contained 420 mg MHE（with 70 mg MHBA）, 210 mg MHE（with 35mgMHBA）, or no MHE for 12 weeks. The primary endpoints were reduction of body weight, body mass index（BMI）, body fat percentage, total fat area and visceral fat area, and the secondary endpoints were reduction of serum triglyceride, subcutaneous fat area and waist circumference after continual ingestion of MHE for 12 weeks. Results Body fat percentage significantly reduced after 12 weeks in both MHE groups compared to the placebo group. A significant reduction was observed in the BMI, total fat area and subcutaneous fat area after 12 weeks in the MHE with 35 mg MHBA group compared to the placebo group. In the subjects which have less than 100 cm2 visceral fat area, significant reduction was observed in the visceral fat area after 12 weeks in the MHE with 35 mg MHBA group compared to the placebo group. No adverse events related to the test samples or clinically relevant abnormal changes in the circulatory, blood and urine parameters were observed in all groups.　Conclusion These results suggest that consumption of a MHE containing MHBA safely reduces body fat.