Unless you're lactose-intolerant or following a vegan diet, dairy products should be a regular part of your daily food intake. Calcium is mostly found in dairy products and works actively to combat belly fat. Skim milk is a good choice because it's low in calories, as well as plain 0% fat yogurt—both are rich in protein and calcium. On top of that, yogurt is full of probiotics, which keep your gut health in check.