When you eat fiber-rich food, you are less likely to feel hungry. When you eat food with a lot of fiber, your digestive process takes a relatively long time to process this. And as long as your digestive system is still processing food, your body will not quickly request new food. With fiber-rich food, you retain your saturated feeling longer. Fruit and vegetables have a relatively high fiber content, certainly in relation to the number of calories it contains. By eating a lot of fruit and vegetables you counteract a hunger feeling and you make slimming easier. For the same reason, it is better to eat brown or whole-grain bread than white bread.