Where Trans Fats Lurk continued...
But trans fats make things a bit more complicated. They get their name from their distinct chemical structure. They occur naturally in small amounts in meat and dairy products. But they can be found in higher quantities in partially hydrogenated vegetable oils which are primarily used in shortening, some margarines and processed foods .
Remember about that hydrogen. When food manufacturers need a more stable, solid form of oil to make their products, they'll bubble hydrogen gas through vegetable oil. The process actually changes the chemical structure of the fat, turning some of it into trans fats. The oil doesn't take up all the hydrogen to become fully saturated, yet it does become a harmful type of fat.
Trans fats are lurking in all commercially made food products containing partially hydrogenated oils or shortening. They are also hiding in frying fats used by many fast food joints. (A 1998 Dutch study estimated that in the frying fat fast food chains use, a third of it is made up of trans fats.)
Be A Trans-Fat Detective
These common foods most likely contain trans fats:
- Most margarines and shortenings;
- Frying fats in processed foods;
- Deep-fried fast food, like french fries;
- And any of food that list "partially hydrogenated oils" in the ingredients, such as: crackers, cake mixes, snack cakes, snack foods, chips, doughnuts, pie crusts, biscuits, breakfast cereals, frozen waffles, microwave popcorn, packaged cookies, and other baked and fried items.
The Daily Dose of Trans Fats
How much trans fats do Americans eat on a daily basis? Good question. It's almost impossible to answer accurately because manufacturers are not yet required to list amounts of trans fats on food labels. And when a product does use the harmful fat, there's no standard amount of how much is in there.
Use The Clues
Until labels give us trans fat information, be sure to check the ingredient list for the words "partially hydrogenated oil" or "shortening." If they are in the first three ingredients for a particular food product, and the food product contains quite a bit of total fat, chances are there is a fair amount of trans fats in that food.
Pay special attention to margarines that list the grams of monounsaturated fat and polyunsaturated fat along with the total grams of fat and grams of saturated fat. With this info, you can actually figure out the grams of trans fatty acids by doing a little math:
- Step 1 -- Add up the grams of saturated fat, monounsaturated fat, and polyunsaturated fat.
- Step 2 -- If the number from step 1 is less than the total amount of fat on the label, you can assume the missing grams are trans fats.