Aloe vera and health outcomes: An umbrella review of systematic reviews and meta-analyses

This umbrella review aims to summarize the effects of Aloe vera on health outcomes and assess the strength of evidence. PubMed, Scopus, Embase, Cochrane database of systematic reviews, CINAHL, and AMED were searched from inception to October, 2019 for systematic reviews and meta-analyses of clinical trials that investigated the effects of Aloe vera on health outcomes. Two independent reviewers extracted data, assessed the methodological quality, and rated the credibility of evidence according to established criteria. Ten articles reporting 71 unique outcomes of Aloe vera were included. Of these, 47 (67%) were nominally statistically significant based on random-effects model (p ≤.05). Only 3 outcomes were supported by highly suggestive evidence, whereas 42 outcomes were supported by weak evidence. The highly suggestive evidence supported benefits of Aloe vera in the prevention of second-degree infusion phlebitis (RR: 0.18, 95% CI: 0.10–0.32, p-value: 1.75 × 10⁻⁹) and chemotherapy-induced phlebitis based on overall incidence (OR: 0.13, 95% CI: 0.08–0.20, p-value: 9.68 × 10⁻²⁰) and incidence of the second degree of severity (OR: 0.10, 95% CI: 0.07–0.14, p-value: 3.41 × 10⁻³⁵). However, the majority of the evidence were limited by small sample size and poor methodological quality. Therefore, despite the overall favorable effect of Aloe vera, more robust studies are needed.