You're doing everything right, and you're still not losing weight. Is it your metabolism? Can you do anything to get your motor running faster?

You dream of a metabolism so fast you could burn through a wedge of chocolate cheesecake or a slab of lasagna just walking the dog. But wake up and smell the science, honey. The nation's leading researchers are about to reveal the hard, fast and slow truth about our calorie-converting engines.

Ten burning questions along with ten expert answers about your metabolism.