Purpose Aframomum melegueta (grains of paradise) seeds have been demonstrated to possess thermogenic potential. However, it is necessary to validate the functional attributes of A. melegueta seed extract in human subjects. Methods In a double-blind, placebo-controlled clinical trial design, we have examined the thermogenic effects of a standardized A. melegueta seed extract (AfperFit). A total of 70 overweight male and female subjects (BMI ≥25.0 to ≤30.0 kg/m 2 ) aged 20–50 years were enrolled and administered with either 250 mg of AfperFit or placebo in capsule form twice daily for 12 weeks. The primary efficacy endpoints included energy expenditure (indirect calorimetry), body composition (dual-energy X-ray absorptiometry (DEXA)) and fat distribution (computed tomography (CT scan)), analyzed at baseline and after 12 weeks of treatment. The effect of intervention on the quality of life was examined using SF-12 questionnaire. Results Consumption of AfperFit significantly increased the energy expenditure ( p <0.01), visceral fat area ( p <0.001) and visceral to subcutaneous fat ratio ( p <0.01) compared to placebo group. Consequently, there was significant body weight loss and reduction in BMI of subjects in AfperFit group compared to placebo ( p <0.01). The safety evaluation showed that biochemical and hematological parameters were in the normal range. Supplementation of AfperFit was well tolerated during the study and no adverse effects were observed. Conclusion Overall, this study validates the health benefits of A. melegueta seed extract as fat burner and recommends its use as a functional ingredient to improve the quality of life and general health.