Trans fats (or trans fatty acids) are created in an industrial process that adds hydrogen to liquid vegetable oils to make them more solid. Another name for trans fats is “partially hydrogenated oils." Look for them in the ingredient list on food packages. Companies like using trans fats in their foods because they’re easy to use, inexpensive to produce and last a long time. Trans fats give foods a desirable taste and texture and makes the food they are in less likely to spoil. Many restaurants and fast-food outlets use trans fats to deep-fry foods because oils with trans fats can be used many times in commercial fryers. Trans fat raises your bad (LDL) cholesterol levels and lower your good (HDL) cholesterol levels. Eating trans fat increases your risk of developing heart disease and stroke and your risk of developing type 2 diabetes. Small amounts of trans fats occur naturally in some meat and dairy products, including beef, lamb and butterfat. The American Heart Association recommends limiting the amount of trans fats you eat to less than 1 percent of your total daily calories. That means if you need 2,000 calories a day, no more than 20 of those calories should come from trans fats. That’s less than 2 grams of trans fats a day!

Additional Resources:

http://www.americanheart.org/presenter.jhtml?identifier=3045792#def_trans_fat