Avoidence of fat in the first place would have accounted for fewer fat cells. Furthermore, when you diet and you become hungry, the body reacts as though you are starving and lowers the metabolic rate. Calories are burned much slower. This is why many diets eventually fail. Food intake may be lower but so is the metabolism.
Some people diet but fail to lose weight.
Another major disadvantage of fat intake is the fact that it leads to increased blood levels of insulin. Diabetics are insulin deficient. However, insulin also increases the absorption of fat into the body as well as blood cholesterol . So when you eat more fat your body produces more insulin which in turn results in the conversion of more calories into body fat. This accounts for the increased incidence of heart disease, high blood pressure, and strokes in overweight people.