by Lynn Baillif, MS, RD, LN, CDE
You may have heard that trans fats are going to be banned in certain states and cities as a public health measure. The following will help you understand what these fats are and why you should minimize them in your diet.
What are trans fats?
Trans fats are manufactured by adding hydrogen to liquid vegetable oil. The result is a product that is solid at room temperature. You may have seen the terms “hydrogenated” or “partially hydrogenated” on food labels. This means the product contains trans fat.
How do trans fats affect my health?
We used to believe that trans fats were a heart-healthy alternative to saturated (animal) fats. Years ago you may have been encouraged to switch from stick butter to stick margarine. However, a growing body of scientific evidence has shown that this is untrue. Trans fats increase the risk of heart disease by raising LDL (“bad”) cholesterol and lowering HDL (“good”) cholesterol thus changing the ratio of HDL to LDL in the body. The Harvard School of Public Health estimates that 30,000 premature cardiovascular deaths per year could be prevented by replacing trans fats in the food supply with liquid vegetable oil (unsaturated fat).
Why are trans fats used in food?
Trans fats were developed in the early 1900s as a low-cost alternative to butter.
They are frequently used in packaged food products because of their extended
shelf life. This means the cookies, crackers and chips in your cabinet will
last longer without becoming rancid. If you look around your kitchen you may
find vegetable shortening (like Crisco) and stick margarine, which are both
high in trans fats. They have a longer shelf life than butter, which contains
no trans fat. You can keep the can of vegetable shortening on your shelf for
1 year. Margarine will keep in your refrigerator for six months compared to
one to three months for butter.
What foods have trans fats?
Although stick margarine is high in trans fat, its use accounts for only one-third of the trans fat intake in the American diet. The vast majority of the trans fat we eat comes from fast food, commercial baked goods and other prepared foods. For example, a donut has approximately three grams of trans fat and a large order of french fries has approximately seven grams of trans fat. So you can see how easy it is for you to consume the eight grams of trans fat each day that is the average intake for Americans.
How do I know if there are trans fats in foods I buy at the grocery store?
As of January 1, 2006, the Food and Drug Administration has required manufacturers to include trans fat on the nutrition facts label. You will find it listed underneath total fat. Products can be labeled as zero grams of trans fat if they contain less than .5 grams trans fat per serving. So, you may see partially hydrogenated oil on the ingredient list even though the label states zero grams of trans fat. In such a case, be careful. If you eat a large amount of the product your trans fat intake can add up.
Can I continue to eat trans fats?
According to the American Diabetes Association 2007 Nutrition Recommendations
and Interventions for Diabetes, you should minimize your consumption of trans
fats. Although there are trace amounts of trans fats which occur naturally in
beef and dairy products, there is no need to avoid these foods since the amounts
they contain are
Should I use margarine or butter?
The answer depends on how often you use it and for what purpose. If you rarely use butter or margarine, having whichever you prefer is fine. Otherwise, it is a good idea to explore this question. Light butter has less unhealthy animal fat than stick butter while tub margarine has less trans fat than stick margarine. As a spread, tub margarine with water or liquid vegetable oil as the first listed ingredient or labeled as “no trans fat” is a wise choice. If your goal is to prevent food from sticking to a pan while cooking or baking you can use a vegetable oil cooking spray or nonstick pans so you do not need to use butter or margarine. When flavoring vegetables, potatoes, popcorn or other foods, try a butter-flavored powder like Butter Buds. It contains no fat. If you prefer the flavor of butter in your homemade baked goods, try using half light butter and half regular butter for the fat in the recipe. You can also decrease the fat in the recipe by one-third without changing the texture of the finished product. Another option when baking is to use a fruit puree (applesauce, mashed banana or baby food prunes) to replace up to three-quarters of the fat in the recipe. But remember this will increase the carbohydrate content of the finished product.
What else can I do to avoid trans fats?
When dining out, ask what type of fat is used in preparing your food. Some establishments are making an effort to reduce their use of trans fats. For example, McDonald’s now uses an oil for cooking french fries that contains no trans fats. Marriott International has undertaken a company wide program to rid its hotel restaurants of trans fats without compromising food quality. However, it is important to remember that even if fried foods and baked goods are made without trans fats, they are still often high in total fat content. We will talk about how to manage your overall fat intake in a future column.