Doctors Answer Your 9 Biggest Health Questions

"If you misrepresent the facts, you limit what your doctor can do for you," says Lissa Hirsch, MD, an obstetrician and gynecologist at Lenox Hill Hospital in New York City. Some of your lies will be revealed by your blood work or the number on the scale, but otherwise your doctor has nothing to go on but what you report—and that could be dangerous. Say you fib and tell her you're following a diet and exercise program to lower your blood sugar. When your "plan" doesn't seem to be working, she may prescribe medication you don't need, unwittingly putting you at risk for unnecessary side effects. In other words, when your pants are on fire, you'll be the one who gets burned.