Prolonged Treatment with Grains of Paradise (Aframomum melegueta) Extract Recruits Adaptive Thermogenesis and Reduces Body Fat in Humans with Low Brown Fat Activity.

Increasing adaptive thermogenesis through the activation of brown adipose tissue (BAT) is a promising practical strategy for preventing obesity and related disorders. Ingestion of a single dose of 40 mg of an extract of Grains of Paradise (GP), a ginger family species, reportedly triggers BAT thermogenesis in individuals with high but not in those with low BAT activity. We hypothesized that prolonged treatment with GP might revive BAT in individuals who have lost active BAT. In the present study, we recruited 9 healthy young male volunteers with reduced BAT that was assessed by fluorodeoxyglucose positron emission tomography and computed tomography (FDG-PET/CT) following 2-h cold exposure at 19ºC. The subjects ingested GP extract (40 mg/d) or placebo every day for 5 wk. Before and after the treatment with either GP or placebo, their body composition and BAT-dependent cold-induced thermogenesis (CIT)-a non-invasive index of BAT-were measured in a single-blinded, randomized, placebo-controlled cross-over design. Their whole-body resting energy expenditure at a thermoneutral condition remained unchanged following GP treatment. However, CIT after treatment was significantly higher in GP-treated individuals than in placebo-treated individuals. Body weight and fat-free mass did not change significantly following GP or placebo treatment. Notably, body fat percentage slightly but significantly decreased after GP treatment but not after placebo treatment. These results suggest that repeated ingestion of GP elevates adaptive thermogenesis through the re-activation of BAT, thereby reducing body fat in individuals with low BAT activity.