Food manufacturers have substantially decreased the amount of trans fat in their products, researchers have found.
But scientists cite a lack of progress in more recent times, arguing that further cuts should be made in the fight against heart disease.
Still, the news is mostly heartening to nutrition advocates.
In 2007, researchers identified 360 brand-name products that contained at least half a gram of trans fat or more per serving. By 2011, the researchers found, two thirds of the products remaining on the market had cut their trans fat content. In most instances, trans fat—otherwise known as partially hydrogenated oil—was lowered to less than half a gram per serving.
The findings were published Thursday in the peer-reviewed journal, Preventing Chronic Disease, by scientists at Harvard and the Center for Science in the Public Interest.
Among the 270 products studied, most of the progress occurred between 2007 and 2008, when the average trans fat content decreased by 30%. Between 2010 and 2011, the amount of trans fat was only reduced by 3.4%.
"Industrially produced trans fats are powerful promoters of heart disease, so it is welcome news that food manufacturers are using less," senior author Dr. Dariush Mozaffarian of Harvard School of Public Health and Harvard Medical School said in a statement. “But, we found that reformulations to reduce trans fat significantly slowed over time, and we also found large variations in reformulations among different food categories and companies."
Doughnuts, crackers and pies represented the largest gram-per-serving reductions in trans fat. On the other end of the spectrum, rolls, margarines and microwave popcorns reduced their trans fat content by the smallest percentages.
The U.S. Food and Drug Administration should get some credit for the reduction in trans fat. Seven years ago, the agency required that Nutrition Facts Labels include a listing of the substance, prompting food manufacturers to make changes, according to researchers.
“Products that contain less than half a gram of trans fat per serving may list zero grams on Nutrition Facts labels. But even those can contribute harmful levels of trans fat," Dr. Fadar Otite, a researcher at Harvard School of Public Health and co-author of the study, said in a statement. "That’s particularly true for something like microwave popcorn, where one might well consume several servings at once."
