- hydrogenated fats
- hydrogenated vegetable oil
Trans fats are formed by the partial hydrogenation of vegetable oil. This process is used to make vegetable oil more solid. An example of this is stick margarine, which is made from liquid vegetable oil.
In what food source is the nutrient found?
Trans fats are found in foods made with or cooked in hydrogenated vegetable oil. These include crackers and fried snack foods, such as potato chips. Trans fats are found in baked goods, such as cookies, cakes, and doughnuts. Margarine and hydrogenated vegetable shortening also contain trans fats.
Trans fats are found naturally in some meats and dairy products. Foods containing hydrogenated fat do not go stale as quickly as foods containing unsaturated fat; thus, foods made with it can stay on supermarket shelves longer. It gives commercially prepared foods a taste and texture similar to regular fat. It is less expensive than butter and more stable than unsaturated fat.
Hydrogenated vegetable oil is often chosen for deep-frying. Many restaurants use it. If the ingredients list includes partially hydrogenated vegetable oil, then the food contains trans fats. Ingredients are listed on all food packages. As of January, 2006, the U.S. Food and Drug Administration (FDA) has required that trans fats be part of these listings. More snack foods with zero trans fat are now becoming available.
How does the nutrient affect the body?
Trans fats raise LDL cholesterol levels. LDL is known as "bad" or "lethal" cholesterol because high levels of it are linked to athersclerosis, the plugging of the arteries that leads to heart disease and stroke. Trans fats may also lower HDL cholesterol. HDL is known as "good" cholesterol because it carries harmful fats to the liver, where they are removed from the bloodstearm.
Trans fats tend to raise total blood cholesterol levels, though not as much as saturated fatty acids do. Trans fats produced artificially are thought to be more harmful than those occurring naturally.
The relationship between trans fat and cancer risk is not clear. Some research has suggested that trans fats might increase the risk of breast cancer. Other equally good studies have not confirmed this observation. The best thing is to reduce the intake of all solid fats in order to reduce the risk of heart disease and, perhaps, cancer.
The American Heart Association recommends the following to limit the intake of trans fats:
- Choose liquid or soft tub margarines. Use them in moderation. In general, the softer the margarine, the less trans fat it contains. Margarines made without trans fat are now available.
- Use naturally occurring, unhydrogenated oil such as canola or olive oil when possible.
- Look for processed foods made with unhydrogenated oil, rather than hydrogenated or saturated fat.
- Use margarine as a substitute for butter. Choose soft margarines (liquid or tub varieties) over harder, stick forms. Shop for margarine with no more than 2 grams of saturated fat per tablespoon and with liquid vegetable oil as the first ingredient.
- Limit intake of french fries, doughnuts, cookies, crackers, and other foods that are high in trans fatty acids. Look for the label on the product and select those snacks that have zero trans fats.