Cocktails and Consequences

You could forgive the average woman for being confused about how much alcohol she should be drinking, or even whether she should be drinking at all. Headlines over the last decade have linked moderate alcohol consumption to everything from a higher risk of breast cancer to a lower risk of dementia. Even the notion that pregnant women should never drink may be debatable. Just this month, a British study suggested that binge drinking—on a very occasional basis—might not be harmful to the fetus (though researchers cautioned that more investigation was needed).

As doctors continue to sort through the contradictory evidence, one thing remains certain: decisions about drinking are more loaded for women than for men. "The benefits of alcohol are going to vary by individual, depending on genes and lifestyle," explains Samir Zakhari, director of metabolic research at the National Institute of Alcoholism and Alcohol Abuse. "But the risks--which we know much more about—those clearly vary by gender, and are much higher for women." Here's what we know—and don't—about how alcohol affects the female body:

1. Gender Benders 
The differences between men and women can be stark when it comes to the way alcohol affects them. For example, if two people, of opposite genders but equal weight drink the same amount and type of alcohol, the woman will get drunker, and stay that way longer. 

The reasons come down to basic physiology. Alcohol passes through the digestive tract and is dispersed in the body's water. Because women always have less water in their bodies, the alcohol is less dilute for them. Women's bodies also produce less alcohol dehydrogenase (ADH)—the molecule responsible for breaking alcohol down so that the body can eliminate it. Less water and less ADH means more alcohol stays in the body, for longer periods of time. "It's like taking the same amount of alcohol and putting it into a much smaller glass," explains Michael Charness, a Harvard Medical School neurologist.

This biologic difference not only means that women have to be careful during those infamous college drinking games, but long-term, women are more likely than men to develop alcohol-related liver disease and brain damage. And women are just as likely to develop alcohol-related heart diseases as men, even though they still tend to drink less alcohol over a lifetime.

Intoxicated women are also far more likely to be the victims of date rape or sexual assault than men. And they are more prone to alcohol-induced blackouts, which can make reporting such attacks difficult.