Trans fatty acids are commonly called trans fats. There are two types of trans fats, naturally-occurring and artificial trans fats. Naturally-occurring trans fats are found in the guts of some animals and foods which are made from these animals. Artificial trans fats are made in an industrial process. The process adds hydrogen to liquid vegetable oils to make them more solid. Trans fats are worse for cholesterol levels than saturated fats. They are most likely found in frying, baked goods, and processed foods.