Become a defensive eater.

Walter C. Willett, M.D., professor of medicine at the Harvard Medical School, offers this advice in his book Eat, Drink, and Be Healthy: “Practice defensive eating strategies.” Here’s how, according to Dr. Willett:
• Practice stopping before you are stuffed.
• Be selective. Don’t eat things just because they are put in front of you.
• Spoil your appetite. Have a low-calorie healthy snack such as carrot or celery sticks before eating a meal.
• Try keeping it simple. Avoid all-you-can-eat buffets and stick with simple, well-balanced meals.