Foods containing trans fatty acids or saturated fats tend to raise levels of low-density lipoprotein cholesterol, which research links to cardiovascular disease. Most animal-based foods contain saturated fat and so do palm and coconut oil. Fried foods and processed foods are the major sources of trans fatty acids.
Food chemists create trans fatty acids by adding hydrogen to vegetable oils. This process retards spoilage but erases the health benefits of using vegetable oils, which normally contain polyunsaturated fat. Nutritionists recommend avoiding all trans fatty acids, but the only way to do so is to look for partially hydrogenated vegetable oil in food ingredient lists. If this oil is present, the product has at least trace amounts of trans fatty acids. Saturated fats provide fatty acids needed to regulate some bodily functions, but calories from saturated fat should make up no more than 10 percent of a healthy diet.