— Judith Dwan, Libertyville, Illinois
A. I was the medical and nutrition expert on the first season of VH1's Celebrity Fit Club. Each week, I would suggest a very reasonable rate of weight loss, and each week the show's producers would say, "More, faster!" The celebrities would then try extreme and unsustainable methods. They fasted, they used laxatives, they swallowed potentially hazardous supplements such as ephedra. And whatever weight they dropped, they tended to gain back.
A far more reliable source of information is the body of research indicating that slower weight loss is better. Study after study demonstrates that the 1-pound-a-week pace that you find frustrating is a sensible, safe rate. Frankly, you're doing better than fine right now. Continue with the sensible eating and regular activity, and you'll be able to sustain your loss.
But if you are adamant about boosting your metabolism, there are some options. Yes, exercise helps—the added muscle and increased lung capacity will help you feel more energetic; you'll stay active and burn more calories throughout your day. Caffeine is a stimulant, and studies show it can boost metabolism a bit—although at the price of insomnia if you overdo it (up to four 8-ounce cups of coffee a day, roughly 340 milligrams of caffeine, is generally the upper limit). An antioxidant in green tea called EGCG may speed metabolism. Other contenders for reducing body fat include calcium and a group of fatty acids known as CLA (conjugated linoleic acid), but their effects are modest at best.