You’re Eating More Trans Fat Than You Think, Study Finds

2 minute read

Scan the grocery store shelves, and you’ll find “0 grams of trans fat” labels nearly everywhere you look. But a new study published in the Centers for Disease Control and Prevention (CDC) journal Preventing Chronic Disease finds that trans fat is still present in many foods, even in those that make the ‘0 grams’ claim.

Trans fats slip into packaged foods via partially hydrogenated oils, cheap vegetable oils that prolong shelf life and contain trans fat. But even if partially hydrogenated oils appear on the label, companies are allowed to claim the product contains 0 grams of trans fat, as long as the amount is limited to between 0-0.5 grams of trans fat per serving. That’s the case for most products containing the oils, the study finds. Of the 4,340 top-selling U.S. packaged foods it surveyed, 9% of them listed partially hydrogenated oils in their ingredients, and 84% of those claimed to have 0 grams of trans fat per serving.

“It’s hard for consumers to know how much trans fat they’re consuming,” says Christine Johnson Curtis, assistant commissioner for the Bureau of Chronic Disease Prevention and Tobacco Control at New York City’s Department of Health and one of the study’s authors. Some of the foods with the most trans fat were baked goods, snacks, frozen foods, and products with seasoning in them, according to the study. In the cookies category, 35% of products contained partially hydrogenated oils.

Studies link trans fats an increased risk of heart disease, and the Institute of Medicine concluded that there’s no safe level of artificial trans fats. Last year, the Food and Drug Administration announced that it’s considering revoking the “generally recognized as safe” (GRAS) status of trans fats.

How will trans-fat-favoring foods be affected? Every category the study analyzed had products free of partially hydrogenated oils. “That means there are always options out there that are trans-fat free,” Curtis says. You may just have to wade through a lot of partially hydrogenated oils to find them.

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Write to Mandy Oaklander at mandy.oaklander@time.com