Q: I heard that trans fats have been banned. Does that mean I can now trust labels claiming "zero grams trans fat," even if the foods contain partially hydrogenated oil?
A: No, unfortunately. In June 2015 the FDA finalized its decision to remove partially hydrogenated vegetable oils from its list of "generally recognized as safe" (GRAS) ingredients, which will in effect eliminate artificial trans fats in foods. But manufacturers have until 2018 to remove these oils from their products. Until then, the labeling of trans fats will remain deceptive.
Trans fats are created when liquid vegetable oils are partially hydrogenated—that is, hydrogen atoms are added to them, turning them into semi-solid fats that have a longer shelf life. That’s good for food companies but not for you, since artificial trans fats are the most unhealthful of all fats, increasing the risk of heart attacks, strokes, diabetes, and other diseases. (Tiny amounts of trans fats are also found naturally in some dairy and meat products, but these do not seem to have the adverse effects of artificial trans fats.)
Since labeling of trans fat content became mandatory in 2006, manufacturers have already eliminated these fats from many processed foods or at least reduced them, leading to a 78 percent drop in per capita consumption.
But thanks to a long-standing labeling loophole, many packaged foods that list “0” trans fats on their nutrition labels actually contain small amounts of these artificial fats. That’s because the FDA has allowed labels to list trans fats as “0” if the foods contain less than 0.5 grams per serving.
This can add up if you eat more than one serving, which is easy to do since standard serving sizes are usually small. You may also eat several foods with small amounts of trans fats throughout the day. Until the trans fat ban goes into full effect in 2018, watch out for partially hydrogenated oils in ingredient lists, even if the labels say “0” trans fat. It’s hard to avoid all trans fats, but eat as little as possible—foods that contain them are generally not the most healthful anyway.