Health statistics routinely show higher morbidity and health services use for women, while mortality rates are higher for men. This analysis empirically identifies reasons for women's poorer health. It is based on retrospective (interview) and prospective (health diaries) data from the Health In Detroit Study. Three kinds of risk factors, which may help explain females' excess, are considered: acquired risks, psychosocial aspects, and health-reporting behavior. Men and women differ markedly in acquired risks: smoking and job hazards are higher for men, but inactivity, nonemployment, stress, and many other factors are higher for women. Psychosocial aspects predispose women to more illness and health care. Women also had keener interest in the survey. When all of the risk factors are controlled, the morbidity gap narrows considerably. In fact, indicators of general and chronic health reverse to reveal higher morbidity for men. Similarly, females' excesses for therapeutic care (short- and long-term disability, medical visits, lay consultation, drug use) diminish when risks and morbidity level are controlled. They actually reverse to a male excess for disability and medical care. Though most of the unveiled male excesses are statistically nonsignificant, their pattern allows a reasonable interpretation. Our results are closely compatible with recent analyses of sex mortality differences in several California sites, which could not eliminate men's mortality excess by controlling for social factors. In conclusion, contemporary women's poorer health profile stems largely from their roles and stress (acquired risks), and to a smaller degree from their health attitudes. When social factors are taken into account, health data suggest a disadvantage for men, and mortality data maintain men's disadvantage. Do the reasons lie in biology?