What are they?
Here’s the scoop:
Trans fat is formed when oil is hydrogenated, or processed to become solid. When hydrogenated fats like margarine and shortening were first invented, they became the ingredient of choice because they were cheaper, more shelf-stable, and thought to be healthier than butter. It was only recently confirmed that this fat is especially unhealthy because it both raises bad cholesterol and lowers good cholesterol.
Trans, or hydrogenated, fat is found in stick margarine, vegetable shortening, and fried foods. Until recently, it was also found in most commercially packaged baked goods, crackers, pastries, cookies, and many other products. However, in 2006, when it became mandatory for companies to list trans fat on food labels, many manufacturers changed their formulas to reduce the amount of trans fat their products contain. You can now find soft margarines that boast “trans fat-free” on their label, and many packaged baked goods are advertised as trans fat-free. However, some foods may contain small amounts of trans fat even if they list zero grams of trans fat in the Nutrition Facts panel (If the amount of trans fat per serving is under 1 g, they can list it as “0” g trans fat. To avoid trans fats completely, check the ingredients list on a product for “hydrogenated” or “partially hydrogenated” oil of any type. If such an ingredient is present, there is still some trans fat in the food. And if the trans fat ingredients are near the top of the list, drop the box and run the other way! And be on your guard in restaurants — unless the menu specifies otherwise, many fried foods are still prepared with hydrogenated oils.