The effects of caffeine intake on weight loss: a systematic review and dos-response meta-analysis of randomized controlled trials

AbstractThis systematic review and meta-analysis of randomized controlled trials (RCTs) was performed to summarize the effect of caffeine intake on weight loss. We searched the following databases until November 2017: MEDLINE, EMBASE, Web of Science, and Cochrane Central Register of Controlled Trials. The relevant data were extracted and assessed for quality of the studies according to the Cochrane risk of bias tool. We estimated an intake-status regression coefficient (Beta) for each primary study and estimated the overall pooled Beta and SE using random effects meta-analysis on a double-log scale. Heterogeneity between studies was assessed by the Cochran Q statistic and I-squared tests (I2). Thirteen RCTs with 606 participants were included in the meta-analyses. The overall pooled Beta for the effect of caffeine intake was 0.29 (95%CI: 0.19, 0.40; Q  =  124.5, I2 = 91.2%) for weigh, 0.23 (95%CI: 0.09, 0.36; Q  =  71.0, I2 = 93.0%) for BMI, and 0.36 (95% CI: 0.24, 0.48; Q  =  167.36, I2 = 94.0%) for fat ...