Half an avocado contains 3.4 grams of fiber, including soluble fiber and insoluble fiber, both of which the body needs to keep the digestive system in order to run smoothly. Soluble fiber will slow down the breakdown of carbohydrates in your body, so it will help you feel full longer.
Avocados also contain oleic acid, the fat that can activate parts of your brain that make you feel full. Healthy unsaturated fats that contain oleic acid have been shown to create a feeling of fullness greater than saturated unsaturated fats and trans fats found in processed foods.
Thus reducing the desire for unnecessary snacking, one of the causes of obesity.