US moves to ban trans fats

The US Food and Drug Administration announced Thursday 7 November that it had reached a “preliminary determination” that partially hydrogenated oils, the primary source of artificial trans fats in processed foods, “are not recognized as safe” for use in food.1

Currently, partially hydrogenated oils have been designated as “generally recognized as safe” (GRAS) for their use in food. Such products can be added to food products without prior approval of the FDA.

Should partially hydrogenated oils lose their GRAS designation, manufacturers would have to prove to the FDA that they are safe by meeting a “reasonable certainty of not harm” standard, something that should prove difficult, given a large body of research indicating that dietary trans fats significantly increase the risk of heart disease by raising blood concentrations of low density lipoproteins.

“While consumption of potentially harmful artificial trans fat has declined over the last two decades in the United States, current intake remains a significant public health concern,” said the FDA’s commissioner, Margaret A Hamburg. “Further reduction in the amount of trans fat in the American diet could prevent an additional 20 000 heart attacks and 7000 deaths from heart disease each year—a critical step in the protection of Americans’ health.”

With the announcement, the FDA opens a 60 day comment period to allow it to collect more data, the FDA said, and to gather information on the amount of time that food manufacturers would need to reformulate their products should the new determination be made final.

Trans fats are commonly used by food manufacturers to improve the flavor, texture, and shelf life of processed food. They are unsaturated fatty acids with at least one double bond in the trans conformation. Trans fats are naturally found in small amounts in dairy, milk, and red meat but can be created by the partial hydrogenation of liquid vegetable oils, which usually have double bonds in the cis conformation. The introduction of the trans conformation converts them into semisolid fats that are more stable and have a thicker consistency. Trans fats are commonly found in fast and snack foods, vegetable shortenings and margarine, coffee creamers, and baked goods.

Their use in products has declined after the FDA required manufacturers to include the amount of trans fat in product nutrition labels. As a result, consumption of trans fats in the US has fallen from 4.6 g a day in 2003 to about 1 g a day in 2012, the FDA estimated. Nevertheless, a substantial number of products still contain partially hydrogenated oils, and they remain a major source of trans fats in the US diet.