Save from: https://www.sharecare.com/health/trans-fats/food-contains-trans-fat
You can figure out if a food contains trans fat by doing a little detective work. On the information label, find the total fat content. Then, subtract the saturated fat and the mono and polyunsaturated fats. This leaves the trans fat. So, for example, if chocolate chip cookies have 12 grams of fat per serving and the label lists 4 grams of saturated fat, the cookies also have 8 grams of artery-aging trans fat.
Another way to tell is to look at the list of ingredients. A food label must list the ingredients in order of quantity, from most to least. If hydrogenated or partially hydrogenated oils are listed early on the list and before polyunsaturated or monounsaturated oils, you know the product contains lots of trans fat. If the label lists unsaturated or monounsaturated oils, olive oil, or canola oil first, the fats are probably okay. Some experts contend that trans fats make up 25 to 60 percent of all fats contained in processed food, and 15 to 30 percent of the total intake of dietary fat. Others disagree, saying the numbers are much lower.