Smoking cigarettes is the number one risk factor for lung cancer, with tobacco products causing up to 90 percent of lung cancer deaths in the United States. 

Without a doubt, the safest way to protect yourself against lung cancer is to avoid smoking cigarettes, and yet, at the same time, it's also true that not all lifelong smokers are doomed to develop cancer.

In fact, the vast majority don't. Scientists have long wondered why, and a new study adds weight to the idea that genetics has a role to play.

Here's we find out The Mystery of Why So Many Lifelong Smokers Never Get Lung Cancer…