Obesity takes a toll on your body even when you're resting. "Excess fat in the abdomen, in particular, forces your lungs to work harder while your're sleeping," says Dr. Kingman Strohl, a pulmonologist at Case Western Reserve University. "Fatty tissue in the throat area also decreases the size of your airway when you're lying down." Nighttime breathing difficulties can take the form of snoring. Just a small weight loss, however, could help the 40 percent of adults who have this problem. In a Florida study of 19 male snorers, a seven-pound loss cut their snoring in half, while a 16-pound loss eliminated it entirely.