Polyphenols are natural compounds and the most plentiful with synergistic properties contributing to potential health benefits. This review describes the synergistic interactions of polyphenolic compounds; as yet, no literature review has been undertaken to consider the experimental evidence of synergistic effects of polyphenols. The polyphenolic compounds claimed to have synergistic activities are highly effective against oxidation, peptic ulcers, myocardial infarction, tumors, and a variety of other conditions. In addition, anticancer activity via apoptosis and antibacterial, antifungal, anti-inflammatory, and estrogenic behaviors have also been reported. Apart from the synergistic effects of polyphenols, this review also illustrates their specific health benefits too and bioavailability in humans. The toxicity of some polyphenolic agents, including antinutritional effects, chronic nephrotoxicity, reduction in net protein utilization and antiluteinizing hormone, and tumor development, is also evaluated. Synergistic treatment approaches may be effective in the treatment of many diseases. These findings provide information about the benefits of polyphenol compounds in combination, which could be useful for future studies.
