Safety and efficacy of herbal supplements used for weight loss

Overweight and obesity are increasing worldwide. Lifestyle change represents the first strategy to counteract the problem, although sometimes a pharmacotherapeutic approach is necessary. People also recourse to herbal products ignoring the real effectiveness and underestimating their safety profile [1]. In this context, the present work aimed at critically evaluating the efficacy and potential risk associated with weight loss botanicals. Only some herbal supplements have been tested for their clinical effectiveness, among these Ephedra sinica, Citrus aurantium, Camellia sinensis (green tea), Garcinia cambogia, and Curcuma longa (turmeric). Often, the products were characterized by a huge variability, in term of kind of preparation, lacked of standardization or used the purified active compounds, whose effects could be different from that of the phytocomplex [2]. Moreover, the weight loss induced was not clinically significant [3]. Conversely, the same botanicals were sometimes associated with adverse reactions (ARs). E. sinica and C. aurantium induced cardiovascular ARs, which led in several countries to their restriction in food supplements. Green tea, G. cambogia and turmeric showed hepatic ARs. Some green tea-based products have been recalled while G. cambogia has never been banned owing to the uncertain causal relationship [4]. Regarding turmeric, supplements involved contained curcumin with enhanced availability or enriched extracts5, thus a pure substance rather than a traditional preparation whith known safety. Considering the poor clinical evidence supporting the use of botanicals for weight loss, the safety concerns become more relevant. A careful evaluation of the risk/benefits profile of these supplements is necessary also considering they are often used as self-medication. References [1] Mazzanti et al., Eur J Clin Pharmacol 2019;75(11):1599. [2] Farrington et al., J Integr Med 2019;17(2019):87. [3] Maunder et al., Diabetes Obes Metab 2020;22(6):891. [4] Yousaf et al., World J Hepatol 2019;11(11):735. [5] Lombardi et al., Br J Clin Pharmacol 2020; doi:10.1111/bcp.14460.