It is known that estrogen increases the risk of breast cancer, which is one of the reasons why post-menopausal hormone replacement therapy (HRT) is so problematic. What makes it more complicated still is that it isn't the estrogen itself, but one of the compounds formed when it is metabolized (broken down) that is responsible for initiating the cancerous changes in breast cells. Estrogen is metabolized by certain enzymes, of which there are two types; one converts estrogen into harmful carcinogens, while the other pathway leads to harmless compounds. These researchers found that resveratrol actually interacts with the cells' DNA to direct the processing of estrogen down the right path by producing the "good" enzymes. Of course this oversimplifies it a bit, but the importance of the study is explaining this capability of resveratrol to actually direct the function of cells by interacting with the "operating system" to keep them on the straight and narrow. There are at least a dozen other anti-cancer properties of resveratrol, and several clinical trials are underway.
So while the question of healthy drinking andbreast cancer remains a source of consternation for many, I would suggest that red wine should at least be the beverage of choice for women who are concerned about breast cancer risk.