The Use of Garcinia Extract (Hydroxycitric Acid) as a Weight loss Supplement: A Systematic Review and Meta-Analysis of Randomised Clinical Trials

Abstract

The aim of this systematic review is to examine the efficacy of Garcinia extract, hydroxycitric acid (HCA) as a weight reduction agent, using data from randomised clinical trials (RCTs). Electronic and nonelectronic searches were conducted to identify relevant articles, with no restrictions in language or time. Two independent reviewers extracted the data and assessed the methodological quality of included studies. Twenty-three eligible trials were identified and twelve were included. Nine trials provided data suitable for statistical pooling. The meta-analysis revealed a small, statistically significant difference in weight loss favouring HCA over placebo (MD: -0.88 kg; 95% CI: -1.75, -0.00). Gastrointestinal adverse events were twice as common in the HCA group compared with placebo in one included study. It is concluded that the RCTs suggest that Garcinia extracts/HCA can cause short-term weight loss. The magnitude of the effect is small, and the clinical relevance is uncertain. Future trials should be more rigorous and better reported.

Figure 1

Flow chart showing the process for the inclusion of randomised controlled trials.

Figure 2

Forest plot of comparison showing the effect of hydroxycitrate on body weight. The vertical line represents no difference in weight loss between HCA and placebo.

Figure 3

Funnel plot of the mean difference in body weight reduction trials of HCA, plotted against sample size. The vertical line depicts the weighted mean difference of all trials.

Figure 4

Effect of dosage of HCA on body weight. The dosages from included RCTs did not produce a linear effect on body weight.