On August 7, 2005, ABC World News Tonight anchorman Peter Jennings died at the age of 67 from lung cancer. Two days later, Dana Reeve, 44, the wife of actor Christopher Reeve who died a year ago after being paralyzed as a result of a riding accident in 1995, announced that she had lung cancer. Recently, Reeve lost her battle with the disease and died on March 6, 2006. One was a smoker (Jennings); the other had never smoked (Reeve).

Many people think that only smokers can get lung cancer. But that is simply not true. According to the Lung Cancer Alliance, over 60 percent of new lung cancers are diagnosed in people who never smoked or who quit smoking even decades ago. Certainly, smoking is the number one cause of lung cancer, but secondhand smoke can be another deadly culprit.

"Secondhand smoke is believed to be the number one cause of lung cancer in lifelong nonsmokers," says Michael Thun, M.D., vice president of epidemiology and surveillance research for the American Cancer Society (ACS). In fact, according to the ACS, nonsmokers married to smokers face a 30 percent greater risk of developing lung cancer than those whose spouses don't smoke. Also, working with people who smoke can be even more troublesome, since you can inhale smoke from many cigarettes at once.

It's also very important to note that lung cancer is the leading cause of cancer death among American women (about 73,000 each year, compared to about 40,000 per year for breast cancer) even though there are more cases of breast cancer than lung cancer diagnosed annually. Apparently, women seem to be particularly susceptible to lung cancer. Though the evidence is not yet conclusive, some studies suggest that a woman's lungs have a genetic predisposition to develop cancer when exposed to tobacco smoke, reports the ACS.

Nonsmokers - both women and men - may also be at risk of lung cancer if they:

• Are exposed to radon, a radioactive gas that can seep into homes and other buildings.
• Work with cancer-causing substances such as asbestos, vinyl chloride, and coal or petroleum products.
• Have had tuberculosis or some type of pneumonia (diseases that can scar lung tissue).

What to Do -- If you're concerned about exposure to secondhand smoke, keep in mind these tips from the Environmental Protection Agency (EPA):

• Never permit smoking in your home or car.
• Insist that if people must smoke that they do it outside, away from doorways and places where nonsmokers frequent.
• Never allow smoking near babies or children. They are particularly vulnerable to the effects of secondhand smoke.
• Insist on a smoke-free work environment. (The EPA recommends that every company protect nonsmokers from secondhand smoke exposure.)

Finally, I recommend eating a diet rich in fruits, vegetables and low-fat dairy products, along with taking a daily multivitamin that contains essential antioxidants, such as vitamins A (in the form of beta-carotene), C and E (in the form of mixed tocopherols)-all of which can protect you not only against lung cancer but from other forms as cancer as well.