Alison Bliven, Dietetic Intern
What is it?
Trans fat has been used since the 1950’s in order to add certain tastes and textures to packaged and prepared foods while also increasing their shelf life. These fats naturally occur in small amounts in some animal products and oils, but the product used in processed foods is man-made and differs slightly from the naturally found substance. Hydrogen ions are forced into oil in a process called ‘hydrogenation’ which turns the oil into a solid. This product is called partially hydrogenated oil (PHO for short) and is filled with trans fats. This PHO is what is used in place of butter or oil in a variety of processed foods in order to keep them fresher longer.
Why is it bad for me?
For half a decade trans fats were included on the Food and Drug Administration’s (FDA) Generally Regarded as Safe list. However, more recent studies have linked the consumption of trans fats to increased risk of coronary heart disease: by raising ‘bad’ cholesterol (LDL) and lowering ‘good’ cholesterol (HDL), trans fat contributes to the buildup of plaque in arteries which can lead to heart attack. Insulin resistance, a sign of Type 2 Diabetes, has also been shown to have strong connections with trans fat intake.
What foods contain trans fat?
Trans fats naturally occur in meat, dairy, and some oils. The amount of trans fats found in these sources make up an insignificant part of the American diet and are not considered a health concern. The majority of trans fats come from processed foods. For example: crackers, cookies, cakes, frozen pies, microwave popcorn, stick margarine, coffee creamer, biscuits, cinnamon rolls and ready to use frosting. Luckily, the number of foods containing trans fats is decreasing, and should soon be nonexistent.
What is being done to protect us?
As mentioned above, studies have overwhelmingly shown a direct connection between trans fats and certain negative health outcomes. This evidence has led to the FDA passing laws that will phase trans fats out of food manufacturing completely. The first step in this process is including the content of trans fats on the nutrition label. This allows the consumer (you) to know what the product contains, to an extent. Food companies are allowed to put ‘0 grams trans fat’ on their labels if the product contains less than 0.5 grams per serving. There are two problems with this: 1) foods with small amounts can add up to a significant intake when more than one serving is eaten and 2) the Institute of Medicine has concluded that there are no safe levels of artificial trans fats in the diet. Even though the FDA is attempting to preserve Americans’ health, there is only so much it can do during the lag time before trans fats are outlawed completely.
What can I do?
Read the label! Look for products that include the phrase ‘trans fat free’ – by law these products can contain no trans fats. Also, scan the list of ingredients for words such as ‘hydrogenated oils’, ‘partially hydrogenated oil’, ‘PHO’, and ‘vegetable shortening’. If the food contains any of these ingredients, there is sure to be some amount of trans fat in it. Other tips include choosing liquid oils or soft tub margarine over stick margarine, and avoiding or limiting commercially baked foods and packaged snacks. Filling up on foods naturally high in fiber (whole grains, beans, peas, fruits, vegetables) means there will be less room for foods containing trans fats and will help promote general health as well.
Remember, Trans Fat Free ≠ Healthy!
One very important takeaway from this article is that just because a food is trans fat free or has very low trans fat, it doesn’t automatically make the food well-balanced or healthy! Limiting trans fats is just one component of a healthful diet that includes lots of fruits and veggies, a focus on whole grains, and limited intake of higher fat meats and dairy products.
(Post content reviewed by MGH Department of Nutrition and Food Services)