Various mechanisms have been proposed to explain their cardioprotective action including scavenging of free radicals; reduction of hydroperoxide formation; decrease in postprandial hyperlipemia, LDL and triglyceride levels; increase in cholesterol
elimination with bile acids; increase in lipid-bound polyphenols,which prevents the lipids from oxidising, reduction of platelet adhesion; and aggregation and inhibition of the release of proinflammatory factors
A total of 75% of grape polyphenols are in the skin and seeds,
but their concentration and composition depend on agro-geographic factors. Therefore, it is interesting to obtain extracts with high concentrations of polyphenols from grape skins and/or seeds so that they can be added to foods and beverages as a nutritional
supplement. However, some reports have also shown that at high concentrations the effect of phenolic compounds on health is negative because products that are highly antioxidant are also cytotoxic