Trans fats, or trans fatty acids, raise "bad" (LDL) cholesterol and lower "good" (HDL) cholesterol, which increases the risk of heart disease, and why they're one of our Scary Seven foods to avoid. However, not all trans fats are necessarily a danger to us. There is a difference between trans fats that occur naturally in the digestive system of ruminant animals like cows, and those that are artificially created by food scientists, like hydrogenated oils.
There are some trans fats in meat and dairy products, but they occur in small amounts. As TFX, a British campaign against trans fats, puts it, any harmful effect from the trans fats in meat and dairy products "is limited and balanced by beneficial effects."
Read more on trans fats and food labels
Artificial trans fats are used in many processed foods such as margarines, dessert products, and snack foods. Only about 20 percent of the trans fats we eat are natural. Most of the trans fats in our diets come from processed oils stabilized to impact flavor and shelf life of foods. A 2010 article by the University of Berkeley's Wellness Alerts suggests that artificial trans fats in processed foods be avoided "as much as possible," and natural trans fats should not be a concern because the "amounts are so low that they don't even show up on nutrition labels."
Reducing trans fats consumption by avoiding artificial trans fats could prevent 10,000 to 20,000 heart attacks and 3,000 to 7,000 coronary disease deaths every year in the U.S., according to the Centers for Disease Control. The American Heart Association (AHA) recommends limiting the trans fats you eat to less than one percent of your total daily calories. For example, if you eat 2,000 calories a day, no more than 20 of those calories should come from trans fats. That is less than two grams a day of trans fats. If you eat a lot of meat and dairy products, then you should be careful to not consume much, if any, artificial trans fats. "Given the amount of naturally occurring trans fats you probably eat every day, this leaves virtually no room at all for industrially manufactured trans fats," the AHA states.
How to reduce trans fats consumption
Australia's Heart Foundation lists ways you can reduce trans fats in your diet, which includes choosing polyunsaturated and monounsaturated spreads and margarines. The other recommendations are:
- Choose lean meat trimmed of all visible fat
- Choose reduced, low or no fat dairy foods
- Try to limit the amount of fast food meals, including deep-fried, and baked foods, including store bought cookies, pastries, pies and cakes that you eat
- Avoid foods that show "hydrogenated oils" or "partially hydrogenated vegetable oils" in the ingredients list.
Read our expose on hidden trans fats
Photo Credit: Scott Ableman