Fats that a person eats, called dietary fats, are a vital source of energy for the body. Dietary fats are important for proper growth, healthy skin, and hair. They also help the body absorb the fat-soluble vitamins A, D, E, and K. Dietary fats can also cause weight gain and can raise LDL cholesterol, or bad cholesterol. High LDL cholesterol can cause heart attacks, strokes, and other health problems. That's why it's important to understand the differences in the types of fats and the dietary recommendations for each type.
There are two main types of dietary fats: saturated and unsaturated. Saturated fats are found mostly in meat and dairy products. These fats are one of the leading causes of high LDL cholesterol in humans, and people should limit foods high in saturated fat. Foods that contain a lot of saturated fats include fatty meats, butter, cheese, and whole milk.
Unsaturated fats can be a healthier alternative to saturated fats. These fats can lower LDL cholesterol when used in place of saturated fat. Unsaturated fats are usually liquid at room temperature. There are two types of unsaturated fats: mono-unsaturated and polyunsaturated. Mono-unsaturated fats include olive and canola oil; polyunsaturated fats include safflower, sunflower, corn, and soy oil.
Hydrogenated fats, also called trans fats, are another type of dietary fat. They are basically unsaturated oils that have been chemically processed into a solid or semi-solid fat. Many researchers believe hydrogenated fats raise LDL cholesterol more than saturated fats do and that they may lower the level of HDL, or good, cholesterol. Many food manufacturers use hydrogenated fats in their products because they spoil less easily than unsaturated fats. French fries, cookies, crackers, doughnuts, muffins, and cakes are examples of foods that are often high in hydrogenated fat and should not be eaten regularly.
The American Heart Association recommends that people limit their daily total fat intake to 25-35 percent of their total calorie intake. It also says to limit saturated fats to less than 7 percent of total daily calories and limit hydrogenated fats to less than 1 percent of daily calorie intake. Other dietary recommendations from the American Heart Association include eating a diet rich in fruits, vegetables, nuts, whole-grain foods, and fat-free and low-fat dairy products; using non-hydrogenated cooking oils such as canola, olive, and safflower oils; and using soft margarine from a tub instead of butter or harder stick margarine. It also suggests that people read labels so they can choose foods made with unhydrogenated oil rather than partially hydrogenated or hydrogenated vegetable oils or saturated fat.