Q. Does secondhand smoke increase my cancer risk? I've heard conflicting information.

A. I love it when I get a question to which I can give a crisp and unambiguous answer. Forget the "conflicting information." On this question, the science is as solid as a rock: exposure to secondhand smoke raises your risk of lung cancer and heart disease, two of the most important causes of suffering and premature death. That is why so many communities have mandated smoke-free indoor public places.

The 2006 U.S. Surgeon General's Report summarizes a large body of research on the health effects of secondhand smoke. The studies involve hundreds of thousands of people. I'm old enough to have seen scientific studies overturn accepted dogma. But that's not going to happen with secondhand smoke. It is bad for your health, period.

—Anthony L. Komaroff, M.D.
Editor in Chief
Harvard Health Letter