I never got anywhere with low-fat diets -- I was hungry all the time, and weight loss levelled off quickly. Doing the low-carb (Atkins) thing, I've lost 50 pounds in less than 3 months, and not having the sugars in my bloodstream has made me more energetic to boot.
While eating habits themselves are a big aprt of the problem, I do think over-liberal use of corn syrups contributes to it -- they get absorbed into the blood stream very quickly (high on the glycimic index) and lead to a "sugar high", which in turn makes you hungry for more.