Results of Margarine Study Downplayed : Health: Dutch research linking margarine with raised cholesterol levels is under attack from U.S. industry officials. They claim the study is unrealistic.
The nutrition community was stunned last week with the release of research indicating that margarine--heavily promoted as a no-cholesterol food--may actually contain compounds that increase potentially harmful cholesterol levels.
The discovery runs counter to popularly held beliefs that margarine is a more healthful alternative to butter because of its lower cholesterol profile.
The study further confuses an already bewildered public about the role of cholesterol and fat in the diet.
“People are saying, ‘What are we supposed to do? And what are we to believe?”’ said Rodney Leonard, executive director of the Community Nutrition Institute in Washington. “The credibility of the nutrition community has really been shaken by this.”
The report, published in the New England Journal of Medicine, stated that trans monounsaturated fatty acids, primarily found in margarines and shortenings, increased low-density lipoproteins, or LDLs, by 6% in a three-week dietary study of 59 adults.
Trans fatty acids are formed when vegetable oil is hydrogenated, or solidified, to create margarine. Elevated LDL levels in blood have been linked to heart disease.
Interviews with consumer advocates, food industry representatives and health researchers in the past week revealed a general dietary consensus: moderation. In other words, individuals at risk for heart disease should reduce their intake of all fats including butter, margarine and oils. Those without a cholesterol problem should continue to monitor fat intake but may still enjoy reasonable amounts of butter or margarine.
“No responsible person is saying substitute butter for margarine,” said Bonnie Liebman, nutrition director for the Center for Science in the Public Interest, a Washington-based advocacy group. “It simply is too early to jump to that conclusion.”
Industry representatives, representing both margarine or butter interests, downplayed the importance of the study, saying excessive amounts of trans fatty acids were fed to subjects and thus produced “unusual” results.
The researchers, Ronald P. Mensink, Ph.D., and Martijn B. Katan, Ph.D., conducted the project at the Agricultural University in Wageningen, the Netherlands.
Their findings also showed that trans fatty acids may even reduce the presence of beneficial high-density lipoproteins, or HDLs, which act to purge the blood stream of harmful compounds.
The Dutch researchers’ work demonstrated that the increases in cholesterol levels caused by trans fatty acids parallel those detected in subjects fed diets heavy in saturated fats.
The study found that LDL levels increased 12% among participants fed a saturated fat diet during the project.
“For the time being, it would seem prudent for patients at increased risk of atherosclerosis to avoid a high intake of trans fatty acids,” the researchers stated.
Theoretically, the dairy industry should be celebrating news that margarine’s ingredients may raise cholesterol levels, therefore better positioning butter in the nutrition world. Not so.
“This is not a renaissance for butter. No, it would not be fair to the public to say that,” said Sharon Long, director of communications for the Dairy Council of California, a nutrition education organization in Sacramento. “We never thought that margarine was sacred or oil was sacred or butter was sacred. All fats should be moderated in the diet.”
Critics of the Mensink and Katan study have also surfaced in the days since the report was published.
“There is no cause for alarm,” said David Kritchevsky, associate director of the Wistar Institute in Philadelphia. “Generally speaking, the amount they fed the subjects was four times the average American intake (of trans fatty acids), so you would expect to see an increase in LDL. If they had fed the people normal amounts, then nothing would have happened.”
The St. Louis-based American Soybean Assn. also took issue with the types of food served in the Dutch study. (About 75% of all margarine produced in this country is made from soybean oil.)
“The (meals) were completely inconsistent with what Americans eat,” said Gunnar Lynum, the association’s marketing vice president. “Even so, the changes they recorded are not that great. (The trans fatty acid) did increase cholesterol levels, but not by as much as when the subjects were fed saturated fat . . . . I don’t think this is a setback for margarine.”
A representative of the National Assn. of Margarine Manufactures in Washington reported no sales declines among members in the well-publicized study’s aftermath.
Richard Cristol, the association’s executive director, said the margarine-like food used in the Dutch study was chemically different than the product sold in this country. He emphasized that butter still contains more saturated fat, a known dietary evil, than does margarine.
“There are two grams of saturated fat in (a tablespoon of) margarine; even less in vegetable oil spreads,” he said. “There are seven grams of saturated fat in (a similar serving of) butter. . . . Margarine remains a healthful alternative to butter.”
The study does present an interesting dilemma for the fast food industry. Many chains recently announced that they would fry foods, particularly French fries, in vegetable oils rather than beef fat.
Leonard, of the Community Nutrition Institute, said that the change may actually increase the amount of fat present on these foods.
Potatoes are more likely to absorb the vegetable fat, and its trans fatty acids, than animal fat, which had previously been used, he said.
The Center for Science’s Liebman said it was too soon to know whether trans fatty acids pose a problem with fast foods.
“We don’t know the exact composition of the oils used in frying (by the chains). You can’t assume that all hydrogenated oils are worse than beef fat,” she said.
