Hidden In Plain Sight

Trans Fat Hides in at Least a Quarter of Supermarket Foods

A new EWG analysis estimates that at least 27 percent of more than 84,000 foods in EWG’s interactive Food Scores database, contain artificial trans fat, a manmade, artery-clogging, industrially-produced fat that bears part of the blame for the American heart disease epidemic.

Another 10 percent of the foods in the database have been made with ingredients likely to contain trans fat.  This means that fully 37 percent of the foods in EWG’s extensive database, which covers a wide variety of items commonly available in supermarkets across the nation, probably or certainly contain a substance strongly implicated in heart disease.

Worse, in most cases, shoppers have no way to make an informed choice to avoid a product with trans fat.  Only two percent of the foods in EWG’s database admit on their labels that they contain trans fat, according to our analysis of information in EWG’s Food Scores, a comprehensive tool with extensive information on ingredients and potential contaminants.  

The vast majority of foods with this substance escape notice by slipping through a federal regulatory loophole that permits trans fat content of less than half a gram per serving to be rounded off to zero. EWG found that 87 percent of  more than 7,500 foods containing partially hydrogenated oils – Americans’ principle dietary source of trans fats -- didn’t disclose that fact.  Instead, the labels of more than 6,500 of these items rounded off their trans fat content to 0 grams.

Because of the trans fat loophole, thousands of nutrition labels on supermarket foods are misleading, and the consequences are serious. Those undisclosed half-gram squirts and dollops of invisible, hidden trans fat add up fast —and even faster for children, who need fewer calories than adults and should consume relatively less trans fat.  A few slices of frozen pizza and a packaged cookie or two can spike a child’s trans fat intake to unhealthy levels.   Serving size is critical – and it’s easy to underestimate.  A person who eats an entire package with several small “servings” can consume multiple grams of trans fat at one time.   

EWG’s findings, the most extensive look to date at hidden trans fats on supermarket shelves are based on information collected in EWG’s Food Scores database and app, unique tools that make it easier for consumers to avoid hidden trans fats in their food.  Food Scores gives worse scores to products that contain partially hydrogenated oils, compared to similar foods that don’t contain these harmful fats. In addition, Food Scores product pages alert consumers to the presence of ingredients that probably or definitely carry small amounts of trans fats, even when the manufacturers take advantage of the trans fat loophole with a nutrition facts panel that says, misleadingly,  “Trans Fat 0.0 g.” 

Figure 1. EWG’s Food Scores informs consumers that trans fat ingredients may be present, even when the Nutrition Facts Panel says “Trans Fat 0.0 g.” 

Available: https://www.ewg.org/foodscores/products/011150992152-RoundysGoldenCremeCakes [Accessed May 20, 2015]

Here’s EWG’s list of the worst of the worst – products with trans fat content of five grams or more – roughly double, or worse, of the World Health Organization’s recommended limit of less than two grams of trans fat daily for a person who consumes about 2,000 calories a day.  

  • Jays Kettles Old Fashioned Kettle Cooked Potato Chips
  • Key Food Popcorn Kettle Corn Sweet & Salty
  • Krasdale Microwave Popcorn Movie Theater Butter
  • Pop Secret Popcorn (Butter, Extra Butter, Homestyle, Jumbo Pop Movie Theater, Kettle Corn, Movie Theater Butter, Old Fashioned flavors)
  • Popz Microwave Popcorn Movie Butter
  • Sealectables Cedar Plank Alaskan Salmon
  • Shop Rite Popcorn (Theatre Style, Whole Grain Kettle flavors)
  • Springfield Microwave Popcorn Kettle Corn Style

Because FDA rules allow food companies to avoid disclosure of trans fat if the levels in a serving are low enough, the true number of processed foods containing trans fats could be even higher than our estimate of 37 percent of supermarket foods.  And it likely is. 

This much is certain: trans fat is ubiquitous in the food supply, thanks to decades of lax regulations, and it’s dangerous.  The food industry claims that it produced only two billion pounds of partially hydrogenated oils in 2012—but that’s enough for 434 grams of trans fat per American – a wildly excessive amount (FDA 2013b).

A single serving of more than 400 products in EWG’s Food Scores contain enough trans fat to exceed the World Health Organization’s recommended limit of less than 2 grams per day for an adult consuming a 2,000 calorie diet.

The Institute of Medicine, an arm of the prestigious National Academies research complex, has gone even further, declaring that trans fats have “no known health benefit… [and] no safe level.”  The Institute of Medicine’s conclusion, issued in 2002, is one factor driving a current effort by the federal Food and Drug Administration to crack down on trans fat in the American diet. Numerous other expert panels agree with the Institute of Medicine’s conclusions.

The FDA is preparing to issue a regulation that, according to some reports, could eventually lead to a drastic reduction in artificial trans fat that, up to now, has been added to a wide variety of commercial goods, including frozen breakfast sandwiches, frozen cakes and pies, frozen pizza, frozen French fries, cookies, crackers, microwave popcorn, non-dairy coffee creamer and other processed foods. 

FDA officials say their plan, unveiled in November 2013, could eventually avert up to 20,000 heart attacks and 7,000 deaths a year – numbers of illnesses and deaths that the U.S. Centers for Disease Control and Prevention attributes to coronary disease caused by trans fat consumption.  The changes FDA officials are contemplating could transform the American food supply for the better.

But that transformation won’t happen overnight. Plenty of devils lurk in the details of the anticipated FDA action.  Though some reports call it a ban, it is more properly described as a phase-out.  The FDA’s November 2013 proposal said that once the agency made its decision final, it would “provide adequate time for producers to reformulate products in order to minimize market disruption.”  If the food industry stays true to form, it is likely to battle for every inch of ground and wind up slow-walking the issue into the next decade.

The final FDA regulation, which could become public in coming days, is unlikely to close the half-gram trans fat loophole in the food labeling law.

In the meantime, consumers need help to make informed choices.  That’s where EWG comes in. To find the truth about the trans fat content of processed food, EWG has looked beyond labeling claims and ad hype.  We programmed our Food Scores database to tell us which supermarket foods contain partially hydrogenated oils. These are vegetable oils that have been hardened through an industrial process called hydrogenation. This process serves to stabilize them, preserve flavor and lengthen the shelf life of the products to which they have been added.  Food processers like partially hydrogenated oils because they give the finished product a creamy texture, are cheap and, by prolonging shelf life, ease the logistics of distributing heavily processed items for a mass market (GMA 2013).  

But public health agencies overwhelmingly have concluded that these oils are the primary source of artificial trans fat in the American diet and a major contributor to the risk of heart disease, the leading cause of death in the U.S.  The CDC says that trans fat increases low-density lipoprotein (LDL, or "bad") cholesterol and may decrease high-density lipoprotein (HDL, or "good") cholesterol, making trans fats even worse for heart health than the saturated fats they were designed to replace. 

The FDA wants to strip partially hydrogenated oils of their favored status as “generally recognized as safe,” or GRAS, food ingredients, a designation that has enabled food processors to add them to food without notifying the agency. If the FDA gets its way, partially hydrogenated oils would be designated food additives.  Food processors could not use them unless the FDA authorized the practice via a specific food additive petition. Since the Institute of Medicine, World Health Organization, CDC and other prestigious health bodies say these oils are not only useless but also dangerous, many observers predict that food companies would have a hard time justifying their continued use.  If the FDA hangs tough in coming years, it can end most uses of partially hydrogenated oils in foods.

Here’s what the FDA plan is unlikely to accomplish, at least immediately:

  • Ban partially hydrogenated oils from food in the short run.  The FDA said that if it takes away the GRAS designation of partially hydrogenated oils, the agency “intends to provide for a compliance date that would be adequate for producers to reformulate any products as necessary and that would minimize market disruption.”  The FDA pointedly avoided saying how much time it would give producers to finish the job of driving these oils and the trans fats they harbor out of food.
  • Completely remove artificial trans fat from the food supply.  An FDA memo documenting a 2013 meeting between agency officials and Grocery Manufacturers Association representatives said that the industry claimed that partially hydrogenated oils had 200 uses in a large number of ingredients (FDA 2013b). Other memos documenting similar meetings said that the industry hoped to find a way to continue using partially hydrogenated oils, likely at levels that would not require disclosure.
  • Close the half-gram artificial trans fat loophole.  Modern scientific instruments have improved to the point that they can detect trans fat at less than a tenth of a gram.  The FDA has not made clear whether it will attempt to narrow the exemption from a half to a tenth of a gram, or somewhere in between.   

Meanwhile, consumers can consult EWG’s Food Scores for information on which specific foods contain these trans fat ingredients.

How trans fats undermine human health

Nearly half of American men and a third of women will develop heart disease during their lifetimes, according to the federal Centers for Disease Control and Prevention (CDC 2013b).

Scores of studies strongly implicate artificial trans fats with an increased risk of heart disease (Mozaffarian 2006; Teegala 2009; Micha & Mozzaffarian 2008).  The risk of heart disease appears to increase with the amount of trans fat consumed by an individual (Brouwer 2013; Oomen 2001; Oh 2005).

Scientists have not determined the mechanism that causes trans fats to contribute to heart disease. The consensus is that they raise the levels of bad (LDL) cholesterol in the blood, reduce levels of good (HDL) cholesterol and increase blood triglycerides —unhealthy fats that thicken the blood, increase the chances of clotting and risk of heart attack and stroke (EFSA 2010; WHO 2003). 

Trans fats may increase oxidative stress and inflammation in the body.  They have been linked to insulin resistance as well (Bendsen 2011; Tarrago-Trani 2006) leading the World Health Organization to assert that trans fat may contribute to development of type-2 diabetes (WHO 2003).

The case against natural trans fat that occurs in dairy and meat is murkier. Some scientists suspect that biological differences exist between natural and industrial trans fats rendering them less damaging (Aldai 2013; Oomen 2001); others have found there to be no difference between natural and artificial trans fats (Laake 2011; Motard-Bélanger 2008).   

Trans Fats Hidden in Many Foods

Trans fats are everywhere in the grocery store

Table 1. Worst 16 Food Categories for Trans Fat

Food Type Average trans fat content per serving (grams)
Breakfast Sandwiches 0.94
Frozen Pies 0.83
Frosting and Icing 0.75
Eclairs and other snack cakes 0.65
Frozen Cakes 0.50
Frozen Mini Burgers 0.47
Croissants 0.43
Frozen Cheesecakes 0.41
Pastry Shells 0.37
Canned Chili without beans 0.36
Ready to heat potatoes 0.33
Frozen muffins 0.33
Beef in a can 0.32
Snack pies 0.32
Cheese sauce 0.32
Popcorn 0.31

Table 2 shows food categories that are the worst at disclosing trans fat. Foods marketed to children dominate these categories. Children’s lower calorie needs and lower trans fat limits make the lack of disclosure of trans fat content even worse.

Table 2. Worst Categories* for Trans Fat Disclosure

Food Type Percentage of foods labeled "Trans Fat 0 g" but contain partially hydrogenated oils
Breakfast Bars 100%
Granola & Trail Mix Bars 100%
Peanut Butter 100%
Pretzels 100%
Crackers 100%
Breads & Buns - Other Bread 100%
Kids Fruit Snack Candy 100%
Kids Cereal 100%
Graham Crackers 100%
Whipped Topping 100%
Non-dairy Creamers 100%
Pudding Mixes 100%
Cupcakes, Finger Cakes, Cake Snack Bars 100%
Ice Cream Cones 100%

* Categories with 25 or more products containing partially hydrogenated oils in EWG’s Food Scores

200 Ways To Smuggle In Trans Fat

EWG’s research found that trans fats are being used by the food industry in undisclosed ways. Beyond partially hydrogenated oils, other types of refined oils, emulsifiers, flavors, colors and other common ingredients contain trans fats in amounts low enough to exploit the trans fat loophole.

Contain trans fats in significant amounts:

  • Partially hydrogenated oils

    Partially hydrogenated oils are made from refined oils, like soybean and cottonseed oils, by subjecting them to a hydrogenation process.  Depending on the extent of hydrogenation, the resulting oils can contain up to 60 percent trans fat (Tarrago-Trani 2006).

Contain trans fats in smaller amounts:

  • Refined oils

    Refined oils such as soybean, canola, cottonseed and corn oil contain small amounts of trans fat (FDA 2013a). Researchers at Health Canada found that canola oil contained the most at 2.4 percent trans fat and extra virgin olive oil the least at 0.05 percent (Ratnayake and Zehaluk 2005).

    Trans fats are generated when crude vegetable oil is refined to a bland, odorless, colorless oil (De Greyt 1999). The processed food industry considers  refining essential to “improve” the oils’ “sensory value" and to make the oils more versatile and interchangeable.

    The refining process impairs the oils’ nutritional value by removing or destroying beneficial plant components. A 2012 study by FDA scientists estimated that refined oil contributes an average 0.6 grams of trans fat a day (Doell 2012).
  • Fully hydrogenated oils

    Fully hydrogenated oils are polyunsaturated oils that started out relatively benign but were subjected to high temperatures to convert them into saturated fats, which are worse for human health. Fully hydrogenated oils contain less trans fat than their partially hydrogenated cousins (FDA 2013a).

Likely contain trans fats in trace amounts:

  • Monoglycerides and diglycerides and other emulsifiers

    Fats and oils  come primarily in the form of triglycerides. Splitting triglyceride molecules with a chemical reaction produces a mixture of monoglycerides and diglycerides, which are very helpful when you’re trying to mix oil and water.  That is why they are common emulsifiers.  They are often, but not always, made from hydrogenated fats (Hasenhuettl and Hartel 2008).  Emulsifiers produced from hydrogenated fats “contain measurable concentrations of trans unsaturated fatty acids,” according to a textbook for food scientists (Hasenhuettl and Hartel 2008).

May contain trans fats in trace amounts:

  • Flavors and Colors

    Flavors often use partially hydrogenated oils as a carrier for the flavor and are another likely source of trans fats.

    Due to lax regulations consumers may never know for sure which flavors or colors (both natural and artificial) contain trans fats.

Small Amounts Matter Even More For Children

Children are perhaps most at risk from the half-gram labeling loophole. A 2012 study found that 80 percent of children under 11 exceed recommended trans fat limits (Kris-Etherton 2012).

According to the World Health Organization’s recommendations, a two-year-old with calorie needs of 1000 calories should consume no more than 10 calories from trans fat, or less than 1.1 grams a day. A food with 0.3 grams of trans fat per serving would make up nearly 30 percent of a child’s daily limit. Two servings of crackers and a bowl of cereal containing partially hydrogenated oil claiming “0 grams of trans fat” could easily exceed a child’s recommended limits.

Table 3. Trans Fat Content of Common Fats and Oils

Oil Grams of Trans Fat per 100 grams
Soybean oil 0.5
Palm oil Unknown
Canola oil 0.4
Partially hydrogenated soybean oil 34.2
Sunflower oil 0.2
Olive oil Unknown
Cocoa butter Unknown
Cottonseed oil Unknown
Corn oil 0.3
Partially hydrogenated cottonseed oil Unknown
Coconut oil 0.0
Vegetable shortening Unknown
Safflower oil 0.1
Palm kernel oil Unknown
Sesame oil Unknown
Partially hydrogenated palm kernel oil 4.7
Peanut oil Unknown
Partially hydrogenated palm oil 31.2
Butter oil Unknown
Partially hydrogenated coconut oil 0.3
Fully hydrogenated cottonseed oil 0.7
Brominated vegetable oil Unknown
Interesterified soybean oil Unknown*
Rice bran oil Unknown
Fractionated palm kernel oil Unknown*
Partially hydrogenated canola oil 27.0
Fully hydrogenated cottonseed oil 0.7
Fully hydrogenated soybean oil 1.1
Fractionated palm oil Unknown
Fully hydrogenated canola oil Unknown
Margarine 19.1 to 24.7
Partially hydrogenated sunflower oil Unknown

Unknown: The USDA laboratory did not  analyze the fat or oil for trans fat content. *Ingredient has no matching entry in the USDA National Nutrient Database. Source: US Department of Agriculture National Nutrient Database for Standard Reference

Table 3 shows 32 of the most common fats and oils listed as ingredients of processed items in EWG’s Food Score. Less than half have complete data on trans fat content.

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