Lung cancer is the leading cause of cancer deaths among men and women in the U.S. — it causes more deaths each year than the next three most common cancers (colon cancer, breast cancer and prostate cancer) combined. The decline after initial diagnosis can be rapid, especially if the disease is diagnosed in its later stages. That’s why it’s important to know what you can do to reduce your risk. Here are 15 lifestyle changes that can help prevent lung cancer.