Fats Help You Control Hunger
Foods that are high in omega-3 fats, unsaturated fats, and saturated fats from whole foods (like lean meat and eggs) tend to have lower glycemic indexes than foods that are low in fat but high in carbohydrates.
What does that mean? Basically, your body takes longer to digest and process foods with lower glycemic indexes than it does foods with higher glycemic indexes. Sugars and other simple carbohydrates are very easy for the body to digest, so they have higher glycemic indexes. This is why you get a rush of energy when you eat something sugary but then you crash a couple of hours later when your body has processed it and has no other fuel to burn.
When you eat foods that are rich in good fats, they take longer for your body to digest, and so you feel full for much longer than you would on a low-fat, high-carb diet.