When it comes to alcohol, the difference between women and men starts with body fat -- the one place in the body alcohol doesn't go. Since women have more fat than men, the alcohol they drink becomes more concentrated elsewhere in the body. So as a group, women become more intoxicated with less alcohol.

Research is finding other differences as well. In a review of studies published last year in the Journal of the American Medical Association, Dr. Sheila B. Blume found that women got sicker quicker than men, varied in their response to liquor from day to day (in part depending on their menstrual cycles) and were more sexually dysfunctional when intoxicated.

Women alcohol abusers also tend to abuse other substances such as tranquilizers and have histories of both suicide attempts and previous psychiatric treatment.

In the past, women who drank too much often were diagnosed as being depressed or having some other underlying problem. Now doctors are accepting that a woman's primary problem -- just like a man's -- can be alcoholism.

Two recent studies -- one on 100 alcoholic women in Stockholm, and another on about 250 women in Boston -- suggest that alcoholism in women isn't as hidden as prevailing wisdom holds.

"The alcoholic woman isn't hiding," said Blume. "She's in a doctor's office, if you care to look for her . . . The fact that she is middle-class, well-dressed and pays the bills doesn't exclude the diagnosis of alcoholism."

The Swedish study, just published in a Scandinavian medical journal, found that two routine blood tests -- one for the liver enzyme GGT and one for red-blood-cell volume -- were abnormal in two thirds of the alcoholic women.

"It is a clue," said Blume, a psychiatrist who directs programs in alcohol abuse and gambling in Amityville, N.Y., and a professor at the New York State University Medical School at Stony Brook, "that women who have no other reason, such as anemia, for blood abnormalities may have alcohol problems."

The second study, conducted by Dr. Andrea Halliday and published last year, found that in a Boston ob-gyn clinic 12 percent of patients having routine examinations met the criteria for alcohol abuse. "That is twice the number supposedly in the general population," said Blume.

Another study, Blume reported, found that in five-year follow-up examinations of 103 women treated for alcoholism, 31 percent were dead -- four times the expected number for women in the general population.

"Women who had successfully achieved abstinence, however, experienced fewer deaths than expected," Blume wrote.