True or false: If you're trying to slim down, you should switch from sugar to an artificial sweetener.

The answer may be false. According to early studies, the fake stuff could actually lead to overeating.

Your Body Knows the Difference
In a study, lab animals fed saccharin-sweetened yogurt consumed more calories -- and packed on more pounds -- than the animals that ate the treat with sugar added. Like humans, animals are conditioned to expect lots of calories from sweet-tasting foods. But it seems that no-calorie substitutes may put the brain and the body at odds. The brain says, "Mmm, sweet and satisfying," but the body says, "I need more." Time will tell if the results hold true in people, but there are already human studies linking diet soda to excess weight. (Here's another reason diet soda may be bad for you.)

When You Want Something Sweet . . .
Sugar substitutes aren't the only way to cut back on calories while still satisfying your sweet tooth. Try one of these ideas:

• Pile on the berries. These naturally sweet treats are good on cereal, in yogurt, or by themselves in a bowl. And they're chock-full of fiber. (Did you know? Eating fiber-rich fruit could keep you from gaining weight.)
• Skip the no-fat, sugar-free ice cream . . . and make one of these instead: Watermelon-Yogurt Ice or exotic Iced Lychees.
• Think quality, not quantity. A few nibbles of the richest dark chocolate can be more satisfying than a pound of cheap milk chocolate. (Here's what else dark chocolate will do for you.)

For more on the science behind sugar substitutes, read this RealAge report.