1.     Artificial trans fats have been around for almost a century. While recent campaigns to ban trans fats from foods and restaurants might give the impression that trans fats are new, they were first produced in the early 1900s, when a soap and candle maker joined forces with a chemist to find a substitute for animal fats in their products. Trans fats, produced by hydrogenating plant oils, turned out not to be suitable for soaps and candles, but they soon were marketed as a healthier alternative to cooking with animal fats. Cheaper than butter and longer in shelf life, trans fats have long been a popular ingredient in packaged cookies and crackers, and they are found in the oils often used to deep-fry foods such as French fries.

2.     Some trans fats are produced naturally in meat and animal products–and actually may be healthy. In fact, researchers at the UW-Madison Department of Nutritional Sciences are testing a milk product for children that has enhanced levels of conjugated linoleic acid (CLA), a natural trans fat found in animal products, to see if it can mitigate fat weight gain.

3.     As restaurants and packaged-food suppliers rid their recipes of trans fat sources, they are often replacing them with artery-clogging saturated fats. Watch out for palm, coconut or tropical oils, which contain more saturated fat than other vegetable oils, such as corn, soy and cottonseed oils.

4.     Not all fats are bad. The Dietary Guidelines for Americans recommend a diet that derives 20 to 35 percent of total calories from fats. The key is to find sources of polyunsaturated or monounsaturated fats, rather than saturated fats. Corn, soybean and safflower oils, for example, are great sources of Omega-6 fatty acids, which are necessary for the formation of hormone-like fats that promote blood clotting and smooth muscle contraction. Omega-3 fatty acids in soybean oil, canola oil, walnuts and flaxseed reduce pain and inflammation.

5.     The bottom line is that total fat and calories are still important considerations for a healthy diet. While it’s a good idea to keep intake of trans fats to a minimum, it’s just as important to look at the whole picture. If cutting trans fats means increasing the portion of saturated fats in your diet, you may not be doing yourself any favors. Always check the nutritional facts of the foods you eat and compare products.

Sherry Tanumihardjo, a CALS associate professor of nutritional sciences, developed educational materials about fats for the Wisconsin Nutritional Education Program, which aims to help Wisconsin citizens make healthier dietary choices.

This article was posted in Back List, Fall 2007, Food Systems, Health and tagged Food and drink, Food science, Nutritional Science.