It's been thought that thinking about food makes one crave and eat more, but the truth is just the opposite, according to a new study by researchers at Carnegie Mellon University.

When you fantasize about eating your favorite food, it reduces your actual consumption of that food, say the researchers.

"Our studies found that instead, people who repeatedly imagined the consumption of a morsel of food -- such as an M&M or cube of cheese -- subsequently consumed less of that food than did people who imagined consuming the food a few times or performed a different but similarly engaging task," adds Carey Morewedge, the study leader.

The trick is to visualize yourself gorging on the food all-you-can-eat-style, rather than just a solo mental image of the food. This kick-starts a psychological effect called "habituation" (the gradual reduction in motivation to eat more of the food) and prevents actual overeating.

So go ahead and picture sinking your teeth into that sinfully delicious chocolate candy and savoring every bite -- after all they're just fantasy calories.