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Randomized Controlled Trial
. 2016 Mar 9;15:25.
doi: 10.1186/s12937-016-0144-2.

Matured Hop Extract Reduces Body Fat in Healthy Overweight Humans: A Randomized, Double-Blind, Placebo-Controlled Parallel Group Study

Free PMC article
Randomized Controlled Trial

Matured Hop Extract Reduces Body Fat in Healthy Overweight Humans: A Randomized, Double-Blind, Placebo-Controlled Parallel Group Study

Yumie Morimoto-Kobayashi et al. Nutr J. .
Free PMC article


Background: Hops are the main components of beer that provide flavor and bitterness. Iso-α-acids, the bitter components of beer, 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. While there has been little information concerning the identity of the MHBA compounds and their physiological effects, MHBA was recently found to be primarily composed of oxides derived from α-acids, and structurally similar to iso-α-acids. Here, we investigated the effects of matured hop extract (MHE) containing MHBA on reducing abdominal body fat in healthy subjects with a body mass index (BMI) of 25 to below 30 kg/m(2), classified as "obese level 1" in Japan or as "overweight" by the WHO.

Trial design: A randomized, double-blind, placebo-controlled parallel group study.

Methods: Two hundred subjects (male and female aged 20 to below 65 years with a BMI of 25 or more and less than 30 kg/m(2)) were randomly assigned to two groups. During a 12-week ingestion period, the subjects in each group ingested daily 350 mL of test-beverage, either containing MHE (with 35 mg MHBA), i.e. the namely active beverage, or a placebo beverage without MHE. The primary endpoint was reduction of the abdominal fat area as determined by CT scanning after continual ingestion of MHE for 12 weeks.

Results: Compared to the placebo group, a significant reduction was observed in the visceral fat area after 8 and 12 w, and in the total fat area after 12 w in the active group. There was also a concomitant decrease in body fat ratio in the active group compared to the placebo group. No adverse events related to the test beverages or clinically relevant abnormal changes in the circulatory, blood and urine parameters were observed in either group.

Conclusions: The present study suggests that continual ingestion of MHE safely reduces body fat, particularly the abdominal visceral fat of healthy overweight subjects.

Trial registration: UMIN-CTR UMIN000014185.


Fig. 1
Fig. 1
Flow diagram of the progress stages of this study
Fig. 2
Fig. 2
Effects of MHE on abdominal fat areas. Change in VFA (a), TFA (b) and SFA (c). Data are calculated as the degrees of change from the start values at 0 w (∆), and expressed as means (SEM). * P < 0.05, ** P < 0.01 vs. 0 w (by paired Student’s t-test), # P < 0.05 vs. placebo group (by unpaired Student’s t-test). A, Active group (n = 91); P, Placebo group (n = 87). There was a significant effect of group ( P < 0.01), and of time (§ P < 0.01) during the test-beverage ingestion period (by two-way ANOVA)

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    1. Mathieu P, Pibarot P, Despres JP. Metabolic syndrome: the danger signal in atherosclerosis. Vasc Health Risk Manag. 2006;2:285–302. doi: 10.2147/vhrm.2006.2.3.285. - DOI - PMC - PubMed
    1. Kahn BB, Flier JS. Obesity and insulin resistance. J Clin Invest. 2000;106:473–481. doi: 10.1172/JCI10842. - DOI - PMC - PubMed
    1. Eckel RH, Grundy SM, Zimmet PZ. The metabolic syndrome. Lancet. 2005;365:1415–1428. doi: 10.1016/S0140-6736(05)66378-7. - DOI - PubMed
    1. Egras AM, Hamilton WR, Lenz TL, Monaghan MS. An evidence-based review of fat modifying supplemental weight loss products. J Obes. 2011;2011. - PMC - PubMed
    1. Trigueros L, Pena S, Ugidos AV, Sayas-Barbera E, Perez-Alvarez JA, Sendra E. Food ingredients as anti-obesity agents: a review. Crit Rev Food Sci Nutr. 2013;53:929–942. doi: 10.1080/10408398.2011.574215. - DOI - PubMed

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