Even if you changed nothing else about your diet, eating half a grapefruit before each meal may help you lose up to a pound a week!
A compound in the tangy fruit can lower insulin, a fat-storage hormone, and that can lead to weight loss. It's also a good source of protein, and because it's at least 90% water, it can fill you up so you eat less.
For more foods that will help burn fat, check out my friends at Maira Nutrition