Our society has made great strides over the past several decades in achieving gender equality. One area in which there remains a substantial difference, however, is often overlooked_ Women live, on average, five years longer than men. Why is this? My colleague Dr. Ridwan Shabsigh and I addressed this issue in a series of papers we recently published in the International Journal of Clinical Practice. I'll go over some of our more relevant findings.

What are men dying from? The average life expectancy of a male born in 2003 is 74.8 years, compared with 80.1 years for a female. Due to improvements in modern medicine, life expectancy continues to increase each year, and the 5.3 year difference between males and females is actually decreasing (the difference was 7.4 years in 1980). More men than women die of 12 of the 15 leading causes of death, including the top two, heart disease and cancer. Men develop heart disease about 10 years earlier than women, and almost as many men die each year from prostate cancer (30,000) as women die from breast cancer (40,000). Despite these increased death rates, women are more likely to be diagnosed with an illness than men.

What can explain this? We looked at several features of men and women's health behaviors to help find some answers. Probably the most important behavioral difference is that men are more likely to smoke than women and less likely to try to quit. Smoking has been directly linked to increased rates of heart disease, cancers of just about every organ, and strokes, the three leading causes of death. Men are also more likely to be heavy drinkers or illicit drug abusers, which likely results in a relatively smaller portion of the difference. Risky or dangerous behaviors result in much higher rates of death due to accident, suicide and homicide in men than women. It may be surprising, but the answer does not lie with over-eating, as more women are obese than men. (Although men have been doing their part to catch up in the past few years!)

There are likely some biologic differences in the sexes that impact survival. Women have higher levels of estrogen, which has heart-protective effects by, among other things, increasing levels of the "good" cholesterol. Women may have a more active immune system and higher baseline levels of antioxidants. Having a second X chromosome may also provide other genetic benefits.

Finally, attitudes toward health care are also a major factor. Women are more likely to seek care for health problems than men. They go to the doctor and emergency rooms at higher rates than men and are more often admitted to the hospital. They are almost twice as likely to seek out preventive care, which has been demonstrated to improve health outcomes.

How can we narrow this health gap?The easy answer is likely the least practical: improve men's health behaviors. Quitting smoking, drinking less heavily, and losing weight would all help improve men's longevity, but are difficult to accomplish. Perhaps a better place to start would be at the doctor's office. Men are more likely to go to the doctor for problems that affect their quality of life, like baldness or erectile dysfunction, than for preventive care. Evidence has started to grow that erectile dysfunction may be a warning sign for heart disease (which we'll talk about more in a future blog post). As physicians, we need to recognize such subtle warning signs and use office visits to identify men at risk for more serious problems and screen for cancer. As family members, we need to encourage the men in our lives to stop improve their unhealthy lifestyle habits, get to the doctor when they have a problem, and get screened for colon and prostate cancer.

David B. Samadi, MD is the Chief of Robotics and Minimally Invasive Surgery at Mount Sinai School of Medicine in New York City. As a board-certified urologist and an oncologist specializing in the diagnosis and treatment of urologic diseases, kidney cancer, bladder cancer, and prostate cancer, he also specializes in many advanced minimally invasive treatments for prostate cancer, including laparoscopic radical prostatectomy and laparoscopic robotic radical prostatectomy. His Web site, Robotic Oncology, has been translated into six different languages and is one of the most popular urology sites on the Internet.

Dr. Samadi is a board-certified urologic oncologist trained in open and traditional and laparoscopic surgery and is an expert in robotic prostate surgery. He is chairman of urology, chief of robotic surgery at Lenox Hill Hospital and professor of urology at Hofstra North Shore-LIJ School of Medicine. He is a medical correspondent for the Fox News Channel's Medical A-Team and the chief medical correspondent for am970 in New York City. Learn more at roboticoncology.com. Visit Dr. Samadi's blog at SamadiMD.com. Follow Dr. Samadi on Twitter and Facebook.