May 26, 2010 -- Fears that supermarkets and restaurants were substituting trans fat in their products with other high-fat ingredients can be put aside, researchers say.
A study published in the May 27 issue of The New England Journal of Medicine looked at supermarket and restaurant products before and after they were reformulated to reduce trans fat. Trans fat was a ubiquitous ingredient found in many common foods, including cookies, cakes, doughnuts, potato chips, and fish sticks. Eating 5 grams of trans fat per day has been linked with elevated cholesterol and triglyceride levels, both risk factors for cardiovascular disease, and has been directly associated with a 25% increased risk of ischemic heart disease.
Food manufacturers had agreed to reduce the trans fat content in their products to make them healthier, but skeptics questioned whether one fatty ingredient would be substituted for another, such as increased amounts of hydrogenated oils, which help promote the shelf life of many foods.
Not so, says Dariush Mozaffarian, MD, MPH, of Harvard Medical School and Harvard School of Public Health, and Michael F. Jacobson, PhD, and Julie S. Greenstein, MHS, of the Center for Science in the Public Interest, a nonprofit health advocacy group based in Washington, D.C. The research team looked at 83 brand-name packaged and restaurant foods that had been made with trans fat before 2007, but then were reformulated to eliminate the trans fat.
The results showed that:
- Trans fat content was reduced to less than 0.5 grams per serving in 95% of the supermarket products and in 80% of the restaurant foods analyzed;
- After reformulation, 90% of the restaurant foods and 65% of the supermarket products contained levels of saturated fat that were lower, unchanged, or only slightly higher (less than 0.5 grams per serving) after reformulation.
- Overall content of both trans fats and saturated fats was reduced in 96% of restaurant foods and 90% of supermarket products, with average total reductions of 3.9 and 1.2 grams, respectively.
The researchers even looked at McDonald’s french fries, which once contained 13 grams of saturated and trans fats and now have about 3.5 grams. The trans and saturated fats dropped from 7 grams to 4 grams in Gorton’s Crunchy Golden Fish Sticks.
But watch out for Entenmann’s frosted doughnut, which used to have 5 grams of saturated fat and 5 grams of trans fat. Now it is now trans fat-free but contains 12 grams of saturated fat, the researchers report.
'Much Healthier Food'
“This study should alleviate concerns that most food manufacturers and restaurants would simply switch to a shortening high in saturated fat when they reformulated their products without trans fat,” Mozaffarian says. “In only a small handful of baked goods, more saturated fat was added than trans fat subtracted following reformulation. Still, because a gram of trans fat is more harmful than a gram of saturated fat, even those changes represented relative improvements. In the majority of products, trans fat was reduced or eliminated without corresponding increases in saturated fat. In the case of reformulated restaurant foods, not only was trans fat largely eliminated, but saturated fat also was reduced -- making for a much healthier food.”
The researchers said additional steps could be taken to further improve the U.S. food supply. For example, while cutting trans and saturated fats reduces fat content, replacing those fats with healthier polyunsaturated or monosaturated fats such as those found in nuts, seeds, fish, and some vegetables, could help maximize health benefits.
“This paper demonstrates that the U.S. food industry has been generally responsible in replacing partially hydrogenated oils with more healthful oils,” says study co-author Michael Jacobson, PhD, of the Center for Science in the Public Interest. “That should pave the way for the Food and Drug Administration to eliminate partially hydrogenated oils from the food supply. The agency could do that quite easily by stating that it no longer considers partially hydrogenated oil to be ‘generally recognized as safe,’ and give companies a year or two to switch to healthier oils.”