What You Need to Know About Trans Fats or Trans Fatty Acids

The Fat Family:

Unlike other members of the fat family (saturated, polyunsaturated and monounsaturated fats), trans fats, or trans-fatty acids, are largely artificial fats. A small amount of trans fats occur naturally in meat and dairy products.

Hydrogenation:

Trans fats are made by a chemical process called partial hydrogenation. Liquid vegetable oil (an otherwise healthy monounsaturated fat) is packed with hydrogen atoms and converted into a solid fat. This made what seemed an ideal fat for the food industry to work with because of its high melting point, its creamy, smooth texture and its reusability in deep-fat frying.

Shelf Life and Texture:

Partially hydrogenated fats, or trans fats, extend the shelf life of food. They also add a certain pleasing mouth-feel to all manner of processed foods. Think of buttery crackers and popcorn, crispy French fries, crunchy fish sticks, creamy frosting and melt-in-your mouth pies and pastries. All these foods owe those qualities to trans fats.

Worse Than Butter:

Hydrogenated fats were seen as a healthier alternative to saturated fats: using stick margarine was deemed better for you than using butter, yet numerous studies now conclude that trans fats are actually worse. True, saturated fats raise total and bad (LDL) cholesterol levels. Trans fats do the same, but they also strip levels of good (HDL) cholesterol, the kind that helps unclog arteries. Trans fats also increase triglyceride levels in the blood, adding to our risk of cardiovascular disease.

Basically, the more solid the fat, the more it clogs our arteries. Many margarines and spreads are now available with low or zero levels of trans fats, but they are less suitable for cooking and baking. There is also a trans-fat-free shortening, too. Food manufacturers scrambled to reduce or remove trans fats in time for the January 2006 labeling deadline, when trans fats had to be listed on nutrition facts labels. But some have found it a struggle to produce workable, economic alternatives.

McDonald’s and Trans Fats:

In September 2002, McDonald’s announced its intention to drastically reduce the amount of trans fats in its cooking oil by February 2003. By 2006, McDonald’s had managed to cut the amount of trans fat in its chicken products by about 15 percent, but the company had yet to find a suitable alternative fat for its coveted fries, one that didn’t fundamentally alter the taste.

For allegedly not keeping the public informed of its progress, McDonald’s was sued byBanTransFats.com, the group that sued Kraft Foods, which went on to produce trans-fat-free varieties of Oreo cookies. To settle the suit, McDonald’s agreed to pay $7m to the American Heart Association, and spend a further $1.5m to keep the public informed about reducing trans fats.

Eventually, McDonald's announced in early 2007 that it had begun using a trans-fat-free oil in 1,200 of its 13,700 restaurants, with the rest to follow suit.

But Wendy's Led the Way:

America's third-largest burger chain, Wendy's, was the first of the big fast-food chains to to change. Its revamped cooking oil blend reduces trans fats in its chicken and french fries by an average of 95 percent, and even reduces saturated-fat content by an average of 20 percent. KFC is also removing trans fats from its fried products, though it has yet to find an acceptable alternative for its pot pies and biscuits.

Disappearing Trans Fats:

New York City’s Board of Health voted unanimously in December 2006 to ban trans fats in all its 24,000 restaurants, from high-end eateries to fast-food joints, becoming the first city in the United States to impose such a ban. Restaurants will be banned from using most oils containing artificial trans fats by July 2007, and must eliminate artificial trans fats from all its foods by July 2008.

Starbucks joined the bandwagon and announced in January 2007 that it was eliminating trans fats from its stores in 10 metropolitan areas. It had already begun removing trans fats from some of its baked goods before making the announcement. Even Girl Scout cookies have gone trans-fat-free. So the trans-fat tide is turning.

But until there is a widely acceptable, cost-effective way to process cooking oil without producing trans fats, many companies may have a problem replicating the qualities these oils give to processed foods. Many are relying on palm oil, which is high in saturated fat. Some believe palm oil's particular fatty-acid make-up has heart-healthy qualities, but the jury is still out. In general, replacing trans fats with saturated fats doesn't seem much of an improvement.

Food Labels and Trans Fats

While total fat and saturated fat content have routinely appeared on nutrition facts labels for a number of years, the listing of trans fats is relatively new. Until their listing was made mandatory, from January 2006, we had to look for the words "partially hydrogenated …" or "hydrogenated …" in the list of ingredients. The nearer to the top of the list, the higher the level of trans fats; so even when the label didn't offer a trans fat listing, we could make a fair estimate of how much trans fat was lurking inside by looking at the difference between the total fat figure and the saturated and unsaturated fat figures. Obviously the new labeling requirement eliminates that guess work.

Food manufacturers are simply be required to state the number of grams of trans fats per serving. The government’s revised Dietary Guidelines, which were published in January 2005, fell short of recommending a maximum daily intake for trans fats, even though a limit of less than 2 grams or even less than 1 gram had been floated. Instead the recommendation is to "keep trans fatty acid consumption as low as possible."

A word of warning, though: Labels can say "0 grams of Trans Fat" even if partiallyhydrogenated fats are listed in the ingredients, so long as a serving size contains less than 0.5g of trans fats. The catch is that all those fractions of a gram add up if you eat more than a single serving.