Trans-fats are found in shortening, hard stick margarine, cookies, crackers, and snack foods made with partially hydrogenated oil.
Most of trans-fats are man-made. However, a small amount of naturally occurring trans-fat is found in animal products. Be sure to read the food labels when you shop because some foods that claim to be trans-fat free still contain partially hydrogenated oils. Trans-fat free foods can still be unhealthy so be sure to read the ingredients label on processed foods.