Can diet counter drinking risk?
Raising a glass of wine and wishing "salud!" -- health! -- is one of life's many pleasures.
But for women, this well-meaning cheer is a bit hollow: There's mounting evidence that drinking wine and other alcoholic beverages increases the risk of breast cancer.
That's not the image many people have of drinking wine, beer or other alcoholic beverages in moderation. A recent Harvard study of 878 people in Massachusetts found that nearly two-thirds of drinkers -- and about a third of teetotalers -- considered moderate drinking to be safe and healthful. So healthful that about 30 percent of those surveyed said the purported health benefits of alcohol are one reason they drink.
The link between alcohol and breast cancer is something that "almost nobody [participants] in the [Harvard] study had heard about," says lead author Kenneth Mukamal of Boston's Beth Israel Deaconess Medical Center.
Yet just this month, Danish researchers reported more evidence linking alcohol consumption to greater risk of breast cancer in women. These new results offer a cautionary note for younger women and underscore that it's never too soon to go easy on alcohol.
The researchers tracked nearly 10,000 women for 27 years. The amount of alcohol consumed at the time they entered the study is what correlated best with breast cancer risk nearly three decades later, rather than alcohol intake after menopause.
If women do drink, the consensus is to limit alcohol to one drink per day. (A drink is five ounces of wine, 12 ounces of beer or 1.5 ounces of distilled spirits, such as whiskey, tequila or vodka.) But just that amount of alcohol translates to "about a 10 percent increased risk of breast cancer," says Eric Rimm of the Harvard School of Public Health.
More alcohol equals more risk. "Some studies suggest that two or more drinks per day are associated with about a 30 to 40 percent increase in the risk of breast cancer," says JoAnn Manson, chief of preventive medicine at Harvard's Brigham and Women's Hospital. For women who have other risk factors -- a mother or sister with breast cancer, for example -- "that can be a substantial risk," Manson notes.
Just how alcohol raises breast cancer risk is still unknown. Alcohol boosts estrogen and other hormones, which are linked to breast cancer. Mixing alcohol with hormone replacement therapy can be particularly risky, Manson says, since alcohol and estrogen seem to augment each other. "That combination is something to avoid," she adds.
But there may be ways to help cut the risk from drinking alcohol. Folic acid is one nutrient under investigation. Also known as folate, this vitamin is named for the Latin word for leaf because it occurs in green, leafy vegetables, such as spinach. Citrus fruit and dried beans are also rich in folate. Research suggests that women who eat a lot of fruit and vegetables have a lower risk of breast cancer. Bread, cereal, pasta and rice are among the foods fortified with folate, which is also a common ingredient of multivitamins.
So could diets high in folate offer breast cancer protection? In 1998 researchers studied nearly 3,500 women with breast cancer and found no link between folate intake and breast cancer risk.
In drinking women, folate helped
But when researchers looked at women who had at least one drink of alcohol per day, they found that breast cancer risk was greatest among those with the lowest folate intake. "Our findings suggest that the excess risk of breast cancer associated with alcohol consumption may be reduced by adequate folate intake," the team reported.
In March, Manson and her colleagues published a report of a 10-year study of multivitamin use and breast cancer risk in about 40,000 women. Multivitamins did not protect against breast cancer -- except in women who consumed at least one drink daily. Those results "suggest that multivitamin use might help to counteract the elevated risk of breast cancer for women consuming alcohol," Mason says.
But experts say that doesn't mean that it's OK to imbibe and then pop a multivitamin or eat a lot of spinach to compensate.
Nor is there any evidence that one type of alcohol is better -- or worse -- than any other in terms of breast cancer risk. Red wine is often touted for health benefits. But there's "not strong evidence that beer or liquor is likely to increase breast cancer risk more than wine," Manson says.
What counts is how much you drink. The more alcohol consumed, the greater the risk of breast cancer for women.
You can subscribe to the free Lean Plate Club e-mail newsletter at www.leanplateclub.com. Sally Squires is a writer for the Washington Post.