Anyone who's dieted knows that there can be a considerable amount of guilt involved -- especially when you eat foods you're "not supposed to." Recent research suggests that the act of dieting actually enhances cravings for these sorts of foods, and that, subsequently, dieting may be counterproductive.

Women who participated in the study were shown pictures of chocolate or magazine ads not related to food. Researchers found that women who had dieted felt more guilt about chocolate -- guilt that, in turn, could lead to cravings.

According to Karen Pine of the University of Hertfordshire, who led the study, "Instead of helping people to eat more healthily and to cut down on products which are bad for their health, the negative effect induced by dieting appears to have the opposite effect in that it can increase the desire for the actual foods they are trying to avoid."