Choose healthy fats, limited saturated fat, and avoid trans fat. The total amount of fat you eat, whether high or low, isn't really linked with disease. What really matters is the type of fat you eat. The bad fats saturated and trans fats increase the risk for certain diseases. The good fats mono unsaturated and polyunsaturated fatslower disease risk. The key to a healthy diet is to substitute good fats for bad fatsand to avoid trans fats.