A recent study published in the Nutrition Journal found that green tea may be more effective at suppressing appetite than plain water. (Beverages in general help expand your belly with liquid volume so you fill up on less food.) In addition, research shows that green tea gives your metabolism a slight lift. Just don't add sugar — it'll counteract that calorie-burning advantage. Enjoy a cup of hot or iced green tea with breakfast, lunch, and dinner — three cups (or glasses) a day — to maximize your weight-loss efforts.