Polyphenols are a diverse group of naturally occurring compounds found in plants, notably in foods such as fruits, vegetables, tea, coffee, red wine, and cocoa. Their potential role in supporting or treating arteriosclerosis (the thickening and hardening of arterial walls) has been the subject of considerable scientific investigation. The main mechanism by which polyphenols are thought to exert beneficial effects is through their antioxidant, anti-inflammatory, and endothelial-protective properties.

Numerous observational studies and some clinical trials suggest that diets rich in polyphenols, especially flavonoids (a major polyphenol subclass), are associated with lower risk of cardiovascular diseases, including arteriosclerosis. Polyphenols are believed to reduce oxidative stress and inhibit the oxidation of LDL cholesterol, a key factor in the development of arterial plaques. Additionally, they may improve endothelial function and reduce blood pressure, both of which are important in preventing or slowing arteriosclerosis.

However, while there is a growing body of evidence supporting the cardiovascular benefits of polyphenol-rich diets, most of the evidence pertains to dietary patterns rather than isolated polyphenol supplements. Clinical trials with polyphenol extracts or supplements have shown some promise, but results are variable and often limited by small sample sizes and short durations. As such, while the use of polyphenols for arteriosclerosis has scientific support, the evidence is moderate and stronger for dietary intake rather than supplementation.