Whether or not you are overweight, portion sizes of food are a major factor in determining how much you eat. In a recent study, researchers at Pennsylvania State University in University Park measured how much normal and overweight people ate ( Obesity , June 2007). They then fed these people fifty percent larger portions of food at every meal. Both overweight and normal weight people increased their intake of food equally and they continued to eat far more food for the duration of the study.
You might expect that when people overeat, they would eventually reach a point where they feel full and stop taking in too much food. However, this has not been shown to be the case. When people are offered large portion sizes, they continue to eat more food and it doesn't matter whether they were fat or thin when they received the larger portions. More