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opinion | Paula A. Johnson

‘Every cell has a sex’

Research needs to recognize health differences between men and women

Belle Mellor for the Boston Globe

It doesn’t take a medical degree to know that men and women are different, but it will take sex-specific research to better understand how cellular and molecular differences in males and females affect every aspect of our health. The phrase “every cell has a sex’’ captures the essence of how fundamentally different men and women are when it comes to health.

Our cells, the very building blocks of our existence, are infused with differences that cannot be ignored when we study the prevention, detection, and treatment of disease. From cardiovascular disease to lung cancer to Alzheimer’s, the experience of illness is distinct among men and women. Yet often we ignore these health differences, and fund and conduct medical research that is flawed because it fails to recognize sex differences. This failure is an equal rights issue as well as an issue of the quality and integrity of science and medicine.

Twenty years ago, a bipartisan group of legislators working with patients, providers, policy makers, and advocates shone a spotlight on this issue. The result was the passage of the 1993 National Institutes of Health Revitalization Act, a law mandating that women and minorities be included in clinical trials funded by the NIH. In many ways the law has been a success. Since its passage, women have been routinely included in clinical trials, and we have learned how certain diseases present differently in men and women. Still, major inequities persist.

Women are still not included in clinical research in numbers that reflect the prevalence and impact of disease in women. This means that clinical practices — including treatment guidelines and medication dosages — are derived largely from the male physiological perspective. Even at the very early stages of scientific discovery, a gender lens is not considered as there remains a strong bias in research studies to use male animals to study treatments for disease.


Why are we willing to leave women’s health to chance? Why are women who never smoked being diagnosed with lung cancer at rates three times that of men who are non-smokers? Even though cardiovascular disease is the leading cause of death for women in the United States, why are we satisfied with statistics that show only one-third of cardiovascular clinical trial subjects are female? In an age of cutting-edge technology and expansive sources of research data, why is it acceptable that women are 70 percent more likely than men to suffer from depression and we don’t know why?


The fact is we remain complacent about biomedical research. We fail to look at sex differences. We accept pre-clinical research that all too often does not include female animals. We accept clinical trials that do not always adequately include women and do not consistently report the results in a way that allows us to understand the impact of these treatments on women.

Two decades after the historic NIH Revitalization Act, we are on the verge of being able to dramatically improve the health of women. We know that when we apply a gender lens to science and practice, lives are saved. We know that when we invest in women’s health research and in understanding how the health of women and men differ, breakthroughs can occur.

We need to increase awareness of the gender inequities in scientific research and health care and to have organizations that focus on the health of women join forces to demand change. We have the ability to ensure that the next 20 years bring breakthrough discoveries about why sex differences occur — and to use that knowledge to improve the health of women for generations.

Dr. Paula A. Johnson is executive director of the Connors Center for Women’s Health at Brigham and Women’s Hospital and a professor of medicine at Harvard Medical School.