Health effects of foods rich in polyphenols

We have reviewed literature regarding the health benefits of foods rich in phenolic compounds. Numerous epidemiological studies indicate an inverse association between fruit and vegetable intake and the risk for cardiovascular disease (CVD), ischemic stroke, and other chronic diseases. Besides providing essential vitamins, minerals, and dietary fiber, fruits contain polyphenols that exhibit antioxidant, antiinflammatory, and lipid lowering properties. Several types of berries, cherries, black grapes, and tea are rich sources of dietary phenolic compounds. There are a number of in vitro studies that demonstrate that these compounds reduce oxidative stress and inflammatory response. Data from human feeding studies are limited and inconsistent. Regardless of the inconsistencies, results from human intervention studies do show reduction in oxidative stress, markers of inflammation, serum triglycerides and low-density lipoproteincholesterol when the diets were supplemented with fruits or fruit extracts rich in polyphenols. The inconsistencies may be due to the differences in the amount and type of the polyphenols consumed, duration of supplementation, basal diet and health status of the subjects.