too much fat (especially trans fats) in the body can cause diseases. indeed, obesity, meaning too much fat, is sometimes called a disease itself. one disease from excess fat is called "fatty liver". it is a condition which can be resolved by eating different foods. fatty liver is when someone has too many fats in their liver, but it can also be associated by alcohol or metabolic syndrome. fatty liver can be fixed by exercise and better diet. this is one of the hidden danger of fats.