What Replaced Heart-Damaging Partially Hydrogenated Oils (a.k.a. Trans Fats) in Processed Foods?

The interesting case of interesterified fats

Introduced by Procter & Gamble in 1911, Crisco marked the first time consumers were being sold on the virtues of using partially hydrogenated vegetable oil (PHO) in place of butter or lard in cooking. PHO’s soon became the primary dietary source of artificial trans fats in processed foods, said by the FDA to be the cause of “thousands of heart attacks and deaths each year.”

Although partially hydrogenated oils were finally determined to be "Not Generally Recognized as Safe" by the FDA in 2015, there was a long goodbye until 2021 for the PHO-containing products "to work their way through distribution.” While that may have given the illusion that processed foods somehow became safer, Big Food had some other ideas.

What appears to be taking the place of partially hydrogenated oils (PHOs) are oils that have been altered, either chemically or enzymatically, known as interesterified (IE) fats. Interesterification basically transforms an oil into a solid. And interestingly, fats that are changed in this manner behave a lot like partially hydrogenated oils do in terms of texture and allowing products to have a longer shelf life.

If you’re thinking that sounds suspiciously unhealthy, so are a lot of scientists and researchers. In fact, the conclusion that most experts reach on this ingredient is that we know way too little about the effects it may have on our health – especially heart health. To quote Yogi Berra, it sounds like “déjà vu all over again.”

The studies that have been published on IE fats range from conclusions that the “impact on cardiovascular health is unknown,” to “consumption of interesterified fats may be the cause of the continuous increase in cardiovascular deaths in the United States,” to findings that IE fats raise total cholesterol and even fasting blood glucose by nearly 20 percent.

And while many consumers may have become savvy in looking for partially hydrogenated oils on food labels, as far as IE fats are concerned, there appear to be no specific rules on how they are to be listed. Such fats can appear on ingredient labels as “vegetable oils,” “fully hydrogenated oils,” “Palm oil,” “palm kernel oil,” “high stearate” or “stearic rich” fat. As a group of independent researchers commented, those who “rely on and trust regulatory bodies to protect public health are ultimately the ones who may suffer potential health risks from this lack of transparency.”

But there are those who have another idea for you where fats are concerned, an up-and-coming product that also brings back memories, this time of a fat replacement that was the stuff of bathroom humor back in the 1990s.

‘Have your cake and eat it,’ but do you really want to?

The search for a “fat” with zero calories is the stuff that Big Food’s dreams are made of. And industry thought it had that nailed decades ago when olestra debuted in fat-free WOW and Pringles chips.

But it didn’t take long for adverse reaction reports to start coming in, many collected by the consumer group Center for Science in the Public Interest, with people blaming olestra for horrible cramps, terrible diarrhea, and unspeakable smells.

Now comes EPG, a.k.a. esterified propoxylated glycerol, “the revolutionary new” fat replacement that, just like olestra, passes through the body virtually unabsorbed, and voila, results in over 90 percent fewer calories being metabolized than if a real fat were used!

Of course the company behind this brainchild of caloric reduction, Epogee, claims that they have “better chemistry,” and learned from Procter & Gamble and its olestra experience. With EPG we’re told you can “have your cake and eat it” without the fear of anal leakage.

While that is a comforting thought, both the history of no-cal fat replacements and the origins of EPG aren’t quite as reassuring.

Beginning its journey to your plate back in 1989 when Arco Chemical obtained a patent for a process to make further use of its “workhorse chemical” propylene oxide (which is also a player in the manufacture of such diverse things as furniture foams, car seats, waterproof clothing and even the fumigation of nuts), EPG is now poised to be incorporated into foods ranging from baked goods to ice cream to sauces, nut butters and pasta.

Of course, the FDA would have to approve the use of this chemically altered fat ingredient, right? Well, not exactly.

By taking advantage of what’s been called the “fast track” to GRAS, and using the exact same loophole as for olestra, all that the applicant needed was to have a company official sign off on a “GRAS exemption claim” that it has determined EPG is “generally recognized as safe based on scientific procedures” – with no filed petition or FDA analysis of those scientific procedures required.

Note: On March 10, 2025, new Health and Human Services Secretary Robert F. Kennedy Jr., directed the acting FDA commissioner to find out the steps necessary to eliminate this “self-affirmed GRAS (Generally Recognized as Safe) pathway.”

“For far too long, ingredient manufacturers and sponsors have exploited a loophole that has allowed new ingredients and chemicals, often with unknown safety data, to be introduced into the U.S. food supply without notification to the FDA or the public,” Kennedy said.

So despite all the headway made in the removal of PHOs from the food supply, it seems to perfectly illustrate the proverbial one-step-forward and two-steps-backwards principle that is so often characteristic of hard-fought reforms to eliminate harmful additives from processed foods.

From a Consumer’s Guide to Toxic Food Additives by Linda Bonvie and Bill Bonvie.

“A Calendar of Dinners,” a book put out by Procter & Gamble in 1913 contains 615 “tested recipes” all that call for using Crisco. From the book’s preface: “The nation’s food is becoming more and more wholesome as a result of different discoveries, new sources of supply, and the intelligent weighing of values…It seems strange to many that there can be anything better than butter for cooking, or of greater utility than lard, and the advent of Crisco has been a shock to the older generation, born in an age less progressive than our own, and prone to contend that the old fashioned things are good enough.”