Table 1 Clinical studies of the weight-loss effects of capsaicin
TreatmentsYearCountryStudy designSubjects includedBaseline BMISample sizeAge (years)OutcomesAdverse eventsPotential mechanismReference
Capsinoids (6 mg per day for 12 weeks)2009U.S.A.Double-blind, randomized, placebo-controlled trialOverweight individuals30.6 ± 2.4N=8042 ± 8Body weight decreased 0.92 kg; abdominal fat decreased 1.11%NoneIncrease in fat oxidation and genetic polymorphismsSnitker et al. [35]
Red pepper (capsaicin 10 g single meal)1999CanadaProspective studyHealthy individuals25.3 ± 4.7N=2325.8 ± 2.8Decreased appetiteNoneIncrease in sympathetic nervous system activityYoshioka et al. [40]
Capsinoids (10 mg/kg per day for 4 weeks)2007JapanDouble-blind, randomized, placebo-controlled trialMen and postmenopausal women>23N=4830–65Body weight tended to decrease during the 2- to 4-week periodNoneIncreased VO2, energy expenditure, and fat oxidationInoue et al. [37]
Capsaicin (135 mg per day for 3 months)2003NetherlandsRandomized double-blind placebo-controlled studyModerately overweight subjects29.3 ± 2.5N=14018–60Significant increase in resting energy expenditureNoneMore sustained fat oxidationLejeune et al. [36]
Capsinoids (9 mg per day for 8 weeks)2016JapanRandomized double-blind placebo-controlled studyCollege students21.4 ± 1.8N=2020.7 ± 1.2Increased brown adipose tissue (BAT) densityNoneIncreased BAT activityNirengi et al. [43]