Why Trans Fats Are Back in the News Again, and Why You Should Care

FrostingWhat has inspired a rash of recent articles about trans fats, specifically the partially hydrogenated types (which is what most of them are)?  Exactly what are artificial trans fats?  What foods are they in, and why should we avoid eating them? These and related questions  are answered below by the FDA, food scientist Dr. Karin Allen, 2 university newsletters, Consumer Reports, and a Chicago Tribune article.


What made artificial trans fats newsworthy this summer?


In June, the FDA announced the removal of partially hydrogenated trans oils (commonly referred to as PHOs) from its list of ingredients that are" generally recognized as safe" (GRAS). This decision will, eventually "eliminate artificial trans fats in foods," says the University of California, Berkeley Wellness Letter.  However, manufacturers have until 2018 to find replacements for these products.  As the Tufts Health and Nutrition Letter  points out  in its timeline of trans fat discovery, ascendancy, and  demise, the FDA first proposed this ban in 2013.  It take quite awhile for FDA concerns to translate into decisive action. After making a proposal, the FDA allows a lengthy period allowed for industry and the public to respond and object.


Why have most trans fats been banned?


Karin Allen gives these good reasons: "Trans fats have been linked to increased rates

of cardiovascular diseases, such as heart attack and stroke. The FDA estimates that this move [the ban] could “prevent thousands of heart attacks and deaths each year.”


The Tufts Letter quotes this Institute of Medicine 2002 comment: There is "no safe level of trans fatty acids and people should eat as little of them as possible."  These are worse for the human  diet than saturated fats because trans fat increases bad cholesterol  (LDL)  but--unlike saturated fat-- does not increase good cholesterol (HDL).


What is the history of trans fats and the irony involved in their story?


Their discovery and development goes back more than 100 years, but they  became popular during World War II due to shortages of other fats.  Then, in the 1960s, they were promoted as a healthier alternative to butter and lard.  However, in the 1990s, scientists detected a serious problem: though trans fatty acids are unsaturated, they raise cholesterol levels. In 2006, the FDA announced a trans fat labeling requirement on foods so that consumers would, at least, be informed if  this harmful ingredient was in a particular item they were considering for purchase. At long last, this summer, the FDA banned PHOs. They "cannot be sold or used as ingredients in foods after June 2018," Dr. Allen says.


In the U.S., some cities--including  NYC, Boston, and Philadelphia--have banned PHOs in restaurants and bakeries, as has the state of California.  Many other countries also have PHO bans.


Exactly what is a PHO?


Most of the trans fats in our foods are artificial products, commercially created by adding hydrogen to liquid vegetable oils. This change makes them solid at room temperature and increases their shelf life, according to the Tufts Health and Nutrition Letter


So what is done "partially" to give us the "P" in "PHO"?  Dr. Allen explains: "If the hydrogenation reaction is stopped part way through, a mixture of trans unsaturated fats and fully saturated fats is obtained.  This results in a soft, spreadable, solid fat or semi-solid slushy oil.  These products... contain a large amount of trans fats. 


If the hydrogenation reaction is allowed to finish, a completely saturated, very hard fat is made. These products are called fully hydrogenated oils (FHOs), and contain only a very small amount of trans fat. The FDA has not banned FHOs."


Why is replacing PHOs a problem for some manufacturers and some home cooks?


Dr. Allen says, "PHOs were very useful in many ways, and replacing them in some products will be a difficult task. The trans fats in PHOs give baked goods a crispy, fluffy texture; they can be used to keep frostings from melting; and they keep many fried foods from feeling oily. But food companies have been working for years to find good replacements. Since 2006, when the FDA required that trans fat be listed on nutrition facts panels, there has been a large reduction in the amount of trans fats used in commercial products. For example, Crisco® shortening was reformulated in January 2007 so it contained less trans fat. This was done by blending oil, PHOs, and FHOs to create a similar product that still works in most home recipes. However, like many other shortenings, margarines, and spreads, the newer version of Crisco® still contains PHOs. All of these products must be reformulated again by June 2018 so they no longer contain PHOs.


"Most likely, we will see PHO‐free ingredients like shortening come to market first. Foods containing PHOs as an ingredient will be reformulated once a good replacement can be found.

"Home cooks may soon notice that some recipes don’t work as well using the new, PHO‐free shortenings. ... it is difficult to predict how these products will work. But because so many people have been trying to remove trans fats from their diets in recent years, many cookbooks and online baking forums have already given helpful suggestions."


What will the likely substitutes be for artificial trans fats?


None of the probable replacements will be problem-free. Consumer Reports mentions says that, according to the Grocery manufacturers Association, some companies are likely  to switch to switch to one of these:


palm oil and palm kernel oil: These might be used alone or mixed with liquid canola, sunflower, or soybean oil.  But "both palm and palm kernel oils are high in saturated fat, which raises bad cholesterol levels."

soybeans: "Some companies are developing soybeans--through conventional crossbreeding as well as by genetic engineering in a lab." These products will be lower in saturated fat than most trans-fat alternatives, but they may also lead to health and environmental problems and will have no GMO labeling, says Consumer Reports


Are there trans fats that occur naturally in some foods?


Yes, says Dr. Allen, some occur in mammals that are food for humans and  in dairy products.  Trans fats can also be created--but only in small amounts--when oil is heated to a high temperature during normal cooking or processing. 


The major source of natural trans fats in our diets is whole milk and meat fat, says the Tufts Letter. 


How much PHO is still in foods?  Which foods?  How can consumers tell?


Since the FDA required labeling of trans fats, the amount in our foods has decreased about 80%, says the Tufts Letter.  However, it is still used by manufacturers of some products, especially to make these products: "cake frostings, microwave popcorn, frozen pizzas, and other entrées, baked goods, fried foods, coffee creamers, and even chewing gum. "  Here's the FDA list of  foods that may contain PHOs:


  • crackers, cookies, cakes, frozen pies and other baked goods
  • snack foods (such as some microwave popcorn)
  • stick margarines
  • coffee creamers
  • refrigerated dough products (such as biscuits and cinnamon rolls)
  • ready-to-use frostings  [Note: When I checked the nutrition labels on  frosting containers on my supermarket shelf, I found  the Betty Crocker brand, which said "0 trans fat" and Jewel/Osco's Essential brand, which contained 1.5 grams.]


Here are some specific products that the Chicago Tribune lists which contain more than 0.5 gram per portion:  Popeye's Louisiana Kitchen's fries (3.5 g) and Marie Callender's frozen Razzleberry Pie (3.5 g).  Jiffy Pop's butter popcorn has 10.5 grams in one of its stove-top popping pans.   How do these relate to a healthy diet?  According to the Chicago Tribune, the American Heart Association recommends less than 2 grams of trans fat per day in a 2,000-calorie diet.


In cities where PHOs are allowed, some restaurants use them for frying.


Consumers should be told that "0 trans fat" doesn't actually mean no trans fat. The nutrition label on foods can say "0 trans fat" even when the food has a small amount of trans fat.  That's because the FDA allows this if the amount is small, less than 0.5 grams per serving.  The University of California, Berkeley Wellness Letter points out that even this small amount of artificial fats "can add up if you eat more than one serving, which is easy to do since standard serving sizes are usually small.  You may also eat several foods with small amounts of trans fats throughout the day....It's hard to avoid all trans fats, but eat as little as possible--foods that contain them are generally not the most healthful anyway."


To find out if  an edible item contains industrially-made trans fat, check the list of ingredients for the words "partially hydrogenated oil/ shortening)."


How much trans fat do most Americans eat? 


The FDA estimated that it was about 1 gram daily in 2012, down from 4.6 grams in 2003.


 One of many reasons that Maurice Lenell (makers of the ubiquitous girl scout cookies) went out of business was because the FDA  and the company's  customers were urging them to eliminate PHOs, and the company felt those were essential to maintain the high quality of the product.




Our thanks to Dr. Karin Allen (a member of our Shelf Life Advice Advisory Board) for granting us permission to quote extensively from her fact sheet "Partially Hydrogenated Oils and Trans Fats, Information for Consumer":   http://digitalcommons.usu.edu/extension_curall/749/


The above link will  take you to much more information on the science behind the various fats in our diets and the search for good PHO replacements.




Karin E. Allen, Ph.D., Utah State University, Dept. of Nutrition, Dietetics, and Food Sciences

"Partially Hydrogenated Oils and Trans Fats, Information for Consumers"


fda.gov  "FDA Cuts Trans Fat in Processed Foods"



Chicago Tribune,  Business section "Final Days Ahead for Trans Fats," June28, 2015.


Chicago Tribune, "A Chicago cookie tradition crumbles"  August 14, 2015.


Tufts Health & Nutrition Letter, "What Does the Trans Fat Ban Mean to You?"  September 2015.


University of California Berkeley Wellness Letter, "Ask the Experts" column, September 2015.


Consumer Reports,  "FDA to Manufacturers: Cut the Fat," October, 2015. 



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