This green fruit not only adds a soft and creamy texture to your traditionally crunchy salad, but it also helps you slim down in three ways. For one, it's full of fiber to fill you up while you're eating so you eat less, but it also keeps you feeling full. The fiber prevents constipation, which can prevent a round and bloated belly. Avocados are also excellent sources of MUFAs (monounsaturated fats), proven to diminish belly fat. This salad buddy is high in calories, so go for one-quarter of the fruit, which adds 80 calories and 3.4 grams of fiber.