Several friends of mine have discovered that they are highly sensitive to carbohydrates. One actually describes herself as "allergic" to sugar, and must watch her diet extremely carefully to avoid it even as an ingredient. But before she did this, she weighed 60 lbs. more than she does now, and couldn't get it off. Another lost 100 lbs. in a year by cutting out all refined carbohydrates and going for a half-hour walk every day. She also lost her diabetes and high blood pressure. This may or may not have anything to do with you, but it's worth consideration. But the real thing is usually exercise--even walking can be enough.