Diet gurus say that moderation is the key to sustainable weight loss. I agree with moderation in theory, but in reality I have a hard time not having both the French fries with my cheeseburger as well as the dessert. I would rather just get rid of all the extra weight in one fell swoop, by exercising and being in enough of a calorie deficit to lose about 2 pounds a week. The problem is that after about 3 months of this kind of deficit, I finally broke down and had a junk food-eating spree, the likes of which I occasionally wincingly refer to as Cake Week. If you've ever eaten an entire cake over the course of one day, you might understand what I'm talking about.
Weight maintenance is troublesome. If you're teetering on the "I'm about to reach the point where I'll have to lose weight again" edge, it's hard not to think of foods in terms of good and bad. Sure, in moderation there's really no food that's bad, but I'm not sure how good I am at moderation. I prefer to exercise my willpower through absolute rules - no fried foods or sweets of any kind for a month, or low-carb, high-protein everything for two months. Sometimes when I feel like I've blown a day in terms of calories, I will keep right on blowing it. I guess it's just a process you have to tinker with over time, making up less rigid rules for yourself: If I know I'm going out for dinner, I won't overdo it the rest of the day; I'll eat one fruit and one vegetable for a snack today; French fries or dessert. Moderation is an end goal best made in small steps. Difficult, but better than Cake Week.