Did you stick with those programs for 5 years without cheating?
Look at how obese some of the poor blacks in the ghetto are becoming - they eat a diet of almost PURE CARBOHYDRATES...
I must stress that the fats I try to include are CLEAN. I don't eat bacon, sausage, fatty red meat or pork. I don't use margarine or like products.. I eat fatty fish, Flax oil in my protien shakes and some nuts.
Most people CANNOT stick with low fact/low calorie diets, because A} they don't work and B} they are deprivation diets that make people sick or hungry. That's why there are no long term studies that show net losses on low fat - most show net gains because the participants drop out.