Polyphenols and Microvascular Function in Humans: A Systematic Review

Background: Polyphenol-rich dietary sources are acknowledged to have potential cardiovascular health benefits, particularly in reducing cardiovascular disease risk. Methods: This systematic review sought to determine the effect of polyphenol-rich foods and beverages upon microvascular function, which is of considerable importance in its contribution towards the pathophysiology of microvascular-related complications but also in the future development of (macro-vessel) cardiovascular disease. Results: Overall, consumption of polyphenol-rich foods and beverages demonstrate improved microvascular function, although this is dependent upon the polyphenol source, the dose of the product, the duration of consumption and the population group studied. Most subgroups reviewed suggest an overall beneficial effect on microvascular function, particularly grape-derived products, cocoa, tea, pine bark and Rutaceae aurantiae. Other groups remain equivocal and require further study due to the limited research performed to date. Conclusion: Polyphenols are abundant in the human diet and this systematic review demonstrates that they are an inexpensive, non-pharmacological approach for improving cardiovascular health in currently healthy individuals and in populations with microvascular dysfunction.