Why might a person eat fewer servings than recommend by the food guide pyramid and still gain an unhealthful amount of weight

They may have a slow metabolism because they less than they should.

To make up for the lack of calories, your body's metabolism slows, which means it holds on to the calories you do eat for energy.

Rub your hands together twice as long as washing your hands? or make sure to in between your fingers. or wipe ur hands off with a paper towel when done.