Sometimes drinking alcohol is healthy. And sometimes drinking alcohol is harmful. Studies show that one drink per day -- compared with no drinking at all -- can reduce a woman's risk for heart disease and stroke by 50 percent. And other research indicates that older women who drink moderately have better cognitive skills. But there are also downsides for women who drink even moderate amounts of alcohol.

Even as little as one-half drink per day increases the risk of breast cancer -- possibly because alcohol raises estrogen blood levels which can promote growth of breast tumors. Women are also more likely than men to become dependent on alcohol and to experience other consequences too -- including damage to the brain and other organs. One in 13 adults in the United States has a serious alcohol problem -- and at least six million of these adults are women. And because the risk for alcohol-related health issues increase with age, older women should be especially careful of their alcohol intake for the purpose of maintaining health and limiting the odds of a breast cancer diagnosis.

In the interest of balancing the healthful and harmful effects of alcohol, The Harvard Women's Health Watch suggests that women over the age of 65 limit themselves to one drink per day. Or less.