Suggested ban on trans fat begs the question: Are substitutes any healthier?

Health advocates cheered last month's U.S. Food and Drug Administration (FDA) proposal to ban partially hydrogenated oils—which contain trans fats that increase the risk of heart disease—but some wonder whether the substitutes for these fats will be any healthier. An article in Chemical & Engineering News, the weekly newsmagazine of the American Chemical Society, investigates the matter.

Deirdre Lockwood, a contributing editor at C&EN, notes that back in the 1980s, out of concern over saturated fats, many food manufacturers and consumers made a switch from butter to margarine. The latter contains trans fat, but at the time, it wasn't recognized as a threat to heart health. Artificial trans fats proliferated, largely in the form of partially hydrogenated oil. We baked with it. We fried with it. We popped popcorn with it. Within the past two decades, however, its effect on cholesterol—raising the "bad" kind and decreasing the "good" kind—has become clear, and the food industry and consumers are responding. Since at least 2006, food makers and restaurants have been turning to liquid vegetable and tropical oils as alternatives. When they need a solid fat, they use fully hydrogenated oils and other modified fats.

Despite this move away from trans fat, it is still found in some processed foods, though not for long. In November, the FDA revoked the "generally recognized as safe" status of partially hydrogenated oils, effectively banning artificial trans fats in food. For the most part, the alternatives that are replacing trans fats are indeed healthier, Lockwood reports. Then again, the article points out, these fats aren't the only unhealthy ingredient of processed foods, which can also contain high amounts of salt and sugar.

The American Chemical Society is a nonprofit organization chartered by the U.S. Congress. With more than 163,000 members, ACS is the world's largest scientific society and a global leader in providing access to chemistry-related research through its multiple databases, peer-reviewed journals and scientific conferences. Its main offices are in Washington, D.C., and Columbus, Ohio.