Researchers at Pennsylvania State University are providing some key clues to help you to permanent weight loss. They are looking at the effect of the kind of food you eat, and how it affects your ability to lose weight. (The influence of food portion size and energy density on energy intake: implications for weight management. Am J Clin Nutr. 2005 Jul;82(1 Suppl):236S-241S.)

One thing they have shown is that people tend eat food based on how big the portions are. In other words, they found that no matter what the food was, the people ate the same quantity. It didn