Hundreds of dietary supplements are currently marketed as weight loss supplements. However, the advertised health claims of effectiveness for most of these have not been proven. The aim of this study was to critically appraise and evaluate the evidence for effectiveness of cactus pear, Opuntia ficus-indica (OFI), using data from published randomized clinical trials.
We conducted electronic searches in Medline, Embase, Amed, Cinahl, and the Cochrane Library. No restrictions on age, time, or language were imposed. The risk for bias in the studies included was assessed using the Cochrane Collaboration criteria. Two reviewers independently determined the eligibility of included studies, assessed reporting quality, and extracted data.
We identified seven eligible studies, of which five were included. The studies varied in design and reporting quality. Meta-analysis revealed a nonsignificant difference in body weight between OFI and controls (mean difference = -0.83 kg; 95% confidence interval, -2.49 to 0.83; I(2) = 93%). Significant reductions in body mass index, percentage body fat, systolic and diastolic blood pressures, and total cholesterol were observed. Adverse events included gastric intolerance and flu symptoms.
The evidence from randomized clinical trials does not indicate that supplementation with OFI generates statistically significant effects on body weight. Consumption of OFI can cause significant reductions in percentage body fat, blood pressure, and total cholesterol. Few clinical trials evaluating the effects of OFI have been published. They vary in design and methodology, and are characterized by inconsistent quality of reporting. Further clinical trials evaluating the effects of OFI on body composition and metabolic parameters are warranted.