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Chapter One

Why Men Can Outdrink Women

Myths about women and alcohol have always abounded, and only in the mid-1970s, when clinical studies of alcohol-related disorders began to include women, did we begin to get real information. Although we still know far more about men's drinking than women's, researchers have begun to fill in some of the gaps in our understanding of women and alcohol.

There is mixed news for women who like to drink. The Harvard Nurses' Health Study found a U-shaped curve: light to moderate drinkers lived longer than women who were abstinent or heavy drinkers. It isn't clear whether these results are due to the benefits of alcohol or to the generally healthy habits of light drinkers, who may also be more likely to exercise and eat well. The U.S. Department of Health has defined moderate and acceptable alcohol intake for women as one drink a day-five ounces of wine, twelve ounces of beer, or one and a half ounces of eighty-proof distilled spirits (each of these contains 0.5 ounce of pure alcohol). (For men, it's two drinks a day.) Light drinking for women is defined as up to three drinks a week, moderate drinking as four to thirteen, and heavy drinking as fourteen or more. A woman who has two glasses of wine each evening is thus categorized as a "heavy drinker."

While ongoing research is likely to refine the picture, it now seems clear that in certain ways, women are more vulnerable than men to the immediate and long-term consequences of alcohol.

Women metabolize alcohol differently from men. Their bodies have a higher proportion of body fat, which carries little water. This means that alcohol is moreconcentrated in their body fluids. Women also have less of an enzyme that metabolizes alcohol in their stomach lining, so that for each ounce taken, a higher percentage of alcohol enters the bloodstream and liver (an effect that is enhanced by fasting). Fluctuations in hormonal levels during the menstrual cycle can slow the rate of alcohol metabolism, and oral contraceptives also slow it. All these factors probably contribute to the higher blood alcohol concentration in women, which increases the health risks of women who drink,

Take a couple-let's call them Pete and Laurie. Both are thirty-two years old, and both weigh 140 pounds. They drink the same amount. Every night, they have a glass of wine together as they make dinner and chat about their day at work. At the table, they polish off the bottle and open another. By the end of the evening, each has finished four glasses of wine.

What is the medical outlook for Pete and Laurie?

If their drinking remains constant over many years, both Pete and Laurie may suffer a variety of long-term effects. For Laurie, however, the picture may be worse. Her four glasses of wine will get her drunk faster and keep her drunk longer. She runs a significant risk of liver injury such as fatty liver (which is reversible when drinking stops) and more serious disorders such as hepatitis and cirrhosis (for women the risk of cirrhosis of the liver becomes significant at two drinks a day; for men, at six drinks a day). Sooner than Pete, she may develop digestive and nutritional problems such as anemia, peptic ulcers, and folic acid deficiency, which leads to severe diarrhea. A four-year study of 58,000 nurses demonstrated that in women, the risk of developing high blood pressure begins at about two to three drinks per day and increases with each drink. While light drinking may actually help counteract osteoporosis (because it raises estrogen levels), even small amounts of alcohol cause the body to excrete calcium at twice its normal rate. More research is needed to understand the overall effect of alcohol on women's bones.

Laurie's endocrine system may be impaired by alcohol, leading to menstrual irregularities, which increase with a woman's level of drinking. These can lead to infertility and early menopause. If Laurie becomes pregnant and continues to drink heavily, her risk of spontaneous abortion increases, and she also increases her risk of having a baby with some abnormality, including fetal alcohol effects. (Fullblown fetal alcohol syndrome may result from even heavier drinking.) While the infant death rate is 8.6 per 1,000 among women who do not drink during pregnancy, it is 23.5 per 1,000 births among those who have an average of two or more drinks per day.

Laurie is a little nervous about the link between alcohol and breast cancer-some studies suggest that women who drink alcohol may increase their risk of breast cancer by as much as 40 percent-but she was relieved by the 1999 report from the Framingham Heart Study, which followed the drinking habits of 2,800 women for more than forty years, and found that the incidence of breast cancer was roughly the same for all women, even those who had two or more drinks per day. This study, reasonably enough, eased the minds of many doctors and women who drink moderately. Yet the researchers cautioned that they could not draw conclusions about breast cancer among heavy drinkers, because their sample did not include enough women in this category. Earlier studies suggest strongly an increased risk at four to six drinks a day or more, perhaps related to the fact that alcohol raises estrogen levels.

Listening to the radio on her way home from work, Laurie was also pleased to hear about a study conducted by the American Cancer Society, which corroborated other studies that found moderate consumption of alcohol may protect men and women from heart disease. Her local food co-op sent out a flyer drawing on that study, touting the benefits of red wine (which it now sells).

Laurie, then, feels reassured about her drinking habits. But she has been misled...