Trans Fats 101

Where nasty trans fats are hiding, and how to avoid them.

More dangerous than you’d think. (Photo via iStockphoto.)

My journey to become a dietitian started with the discovery of trans fat. Yes, they had been in existence for many years, but I’d been unaware that these unhealthy fats were hiding in my food. It was only after attending a talk on the subject that I made the decision to become a dietitian — and I’ve never looked back.

A lot has happened since then. The Nutrition Facts panel now includes trans fat, some manufacturers have removed the stuff from their foods entirely, and bans on trans fat have been implemented or suggested in multiple cities throughout the country. In fact, Boston, Cambridge, and Brookline have all banned the use of trans fat in restaurants.

All this comes after the discovery that trans fat is detrimental to your heart health. It raises your LDL (“bad”) cholesterol, lowers your HDL (“good”) cholesterol, and it puts you at greater risk for developing heart disease and stroke. The American Heart Association recommends eating no more than two grams of trans fat per day or one percent of your total daily calories if you are eating the typical 2,000 calories per day. The good news: trans fat in food has declined by 50 percent since 2005, according to the Center for Science in the Public Interest. The bad news, though, is that the fat is still around, and it pops up in some unlikely places.

Trans fat extends the shelf-life of foods and aids in taste and texture, so it’s commonly found in pastries, baked products, and fried foods. But because of a catch in nutrition labeling requirements, the front of the food package and the food label can claim zero grams of trans fat — but still have up to 0.49 grams per serving. So if you eat more than one serving, you can easily eat more than the recommended amount of trans fat. The solution? Check the ingredients list. If the words “partially hydrogenated oil” appears in the list, then the product contains trans fat.

The following foods are some of the most frequent trans fat offenders, so if you’re a fan of adding a little whipped cream to your dessert, or snacking on some microwave popcorn, check the food label before your next indulgence:

  • Tortillas
  • Frozen biscuits
  • Whipped cream
  • Powdered coffee creamer
  • Pie crust
  • Doughnuts, pastries, cobbler
  • Microwave popcorn
  • Margarine and buttery spreads