|Citation||Shaito, A.; Posadino, A.M.; Younes, N.; Hasan, H.; Halabi, S.; Alhababi, D.; Al-Mohannadi, A.; Abdel-Rahman, W.M.; Eid, A.H.; Nasrallah, G.K.; Pintus, G. Potential Adverse Effects of Resveratrol: A Literature Review. Int. J. Mol. Sci. 2020, 21, 2084.
|Abstract||Due to its health benefits, resveratrol (RE) is one of the most researched natural
polyphenols. Resveratrol’s health benefits were first highlighted in the early 1990s in the French
paradox study, which opened extensive research activity into this compound. Ever since, several
pharmacological activities including antioxidant, anti-aging, anti-inflammatory, anti-cancerous,
anti-diabetic, cardioprotective, and neuroprotective properties, were attributed to RE. However,
results from the available human clinical trials were controversial concerning the protective e ects
of RE against diseases and their sequelae. The reason for these conflicting findings is varied
but di erences in the characteristics of the enrolled patients, RE doses used, and duration of RE
supplementation were proposed, at least in part, as possible causes. In particular, the optimal RE
dosage capable of maximizing its health benefits without raising toxicity issues remains an area of
extensive research. In this context, while there is a consistent body of literature on the protective
e ects of RE against diseases, there are relatively few reports investigating its possible toxicity. Indeed,
toxicity and adverse e ects were reported following consumption of RE; therefore, extensive future
studies on the long-term e ects, as well as the in vivo adverse e ects, of RE supplementation in
humans are needed. Furthermore, data on the interactions of RE when combined with other therapies
are still lacking, as well as results related to its absorption and bioavailability in the human body.
In this review, we collect and summarize the available literature about RE toxicity and side e ects.
In this process, we analyze in vitro and in vivo studies that have addressed this stilbenoid. These
studies suggest that RE still has an unexplored side. Finally, we discuss the new delivery methods
that are being employed to overcome the low bioavailability of RE.