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On Thursday, the Food and Drug Administration (FDA) announced that it is moving toward significantly limiting–more or less banning–trans fats from foods in the U.S.

The agency decided that trans fats are not safe for human health, and shouldn’t be in foods we eat. So what are they? Trans fats are a byproduct of partially hydrogenated oils (PHOs). By bubbling hydrogen gas through oil under certain conditions, manufactures can turn liquid oils into whatever saturation or thickness that they desire. Such partially hydrogenated oils have become popular because they give foods taste and texture, and in the 1950s, trans fats emerged as a way to increase the shelf life for processed foods such as baked goods.

However, they have also been linked to major health problems such as coronary heart disease, since trans fats build up plaque in the arteries that can contribute to a heart attack. In 1999, the FDA first proposed that manufacturers disclose the amount of trans fat on nutrition labels but that did not become a requirement until 2006.

Now, after reviewing studies on trans fats, the FDA issued a Federal Register notice, which is preliminarily determination that PHOs are no longer “generally recognized as safe” (GRAS). The public, include scientists and other experts in nutrition and health, have 60 days to comment on the FDA’s conclusion, and if after that time the agency still deems that trans fats are unsafe, manufacturers would need to get FDA approval to use PHOs and trans fats in their products. Foods that contain unapproved food additives cannot legally be sold, and therefore are banned.

“This is welcome news and if anything overdue,” says Dr. David Katz, Dr. David Katz, the director of the Yale-Griffin Prevention Research Center and author of the new book Disease Proof: The Remarkable Truth About What Makes Us Well. “The writing on the wall has been there for a long time. I don’t think businesses will be surprised or there will be much push back. Frankly, most shoppers want to avoid trans fat.”

Many companies have already rid their foods of trans fats, and New York City even banned trans fat from restaurant food in 2006.

But, according to the FDA, there are still foods that rely on trans fats, and here are some predictions from industry experts about how these foods will change:

1. Doughnuts: Without trans fats, they may become more oily. Many desserts, like cookies, cakes and doughnuts rely on trans fats to give them a lighter texture. “Only partially hydrogenated oils continue to stay a part of the matrix and don’t exude out of the food,” says Kantha Shelke, a food scientist at Corvus Blue LLC and spokesperson for the Institute of Food Technologists (IFT).

2. Crackers: Trans fats may be replaced by soy bean oil or canola oil.

3. Movie Theater and Microwaveable Popcorn: Popcorn commonly has trans fats, and according to Kristin Kirkpatrick, a wellness manager and registered dietitian at the Cleveland Clinic in Ohio, we will probably more actual butter may replace the trans fats to maintain that popcorn flavor.

4. Frozen Pizza: Any frozen food with many ingredients can contain trans fats, and some easy swaps could include vegetable oils, but some experts worry about what other additives might be added to achieve the same food preserving features that trans fats had. “We don’t want other additives to make these last longer. Do we really want something in our food that can stay in our pantry for three years?” says Kirkpatrick.

5. Coffee Creamers: Anytime there is cream in a product, you can thank trans fats. “We will probably see more soy bean oil or even some vegetables oils used,” says Kirkpatrick. Some brands, like MimicCreme, achieve their thickness with finely lacerated cashews and almonds.

6. Refrigerated Dough Products: “We will probably see canola oil increase more because we know it has some benefits, and it can be very stable in these products,” says Kirkpatrick, of ready-to-bake biscuits and cinnamon rolls.

7. Canned Frosting: The trans fats may be substituted with lard or vegetable oils.

Even with the FDA’s conclusion that trans fats are no longer recognized as safe, it doesn’t necessarily mean all PHOs will be gone for good. It’s still possible for a company to petition the FDA to prove that a specific use of PHO is safe, under the “reasonable certainty of no harm” FDA safety standard, but this would be quite difficult to prove — and make it harder for companies to justify their use.

What worries some health experts is what the food industry will come up with to replace the trans fats. “That question is the potential devil in the details,” says Dr. Katz. “There are other ways to manipulate fat, and we have to be careful we don’t wind up with another bad invention.”