You've probably heard of studies linking red wine consumption with lower rates of heart disease. According to a study reported in the Washington Post, researchers are beginning to understand the scientific basis of this connection.

Red wine contains substances know as polyphenols, which inhibit production of a peptide that causes blood vessels to constrict. Experts believe that vessel constriction may play a major role in the development of heart disease.

The polyphenols in red wine come from the skin of red grapes. Red grape juice provides similar health benefits, but to a much smaller degree than red wine. White and rose wines appear not to offer the same health benefits as red wine.

Some studies suggest that mild-to-moderate consumption of red wine - defined as 1 (4 oz) to 2 (8 oz) glasses daily - can reduce the risks of coronary heart disease.