Bias Is Found in Food Studies With Financing From Industry

New York Times
January 9, 2007

"Bias Is Found in Food Studies With Financing From Industry"

By MARIAN BURROS

Research studies financed by the food industry are much more likely to produce favorable results than independently financed research, a report to be published today said.

The report, in the peer-reviewed journal PLoS Medicine, is the first systematic study of bias in nutrition research.

Of 24 studies of soft drinks, milk and juices financed by the industry, 21 had results favorable or neutral to the industry, and 3 were unfavorable, according to the research led by Dr. David S. Ludwig, director of the Optimal Weight for Life Program at Children’s Hospital Boston and an associate professor at the Harvard Medical School.

Of 52 studies with no industry financing, 32 were favorable or neutral to the industry and 20 were unfavorable. The biases are similar to findings for pharmaceuticals.

Bias in nutrition studies, Dr. Ludwig said, may be more damaging than bias in drug studies because food affects everyone.

“These conflicts could produce a very large bias in the scientific literature, influence the government’s dietary guidelines which are science based,” he said in an interview. “They also influence the advice health care providers give their patients and F.D.A. regulations of food claims. That’s a top-order threat to public health.”

The American Beverage Association, which sponsored at least one study in the article, said the authors had their own biases.

“This is yet another attack on the industry by activists who demonstrate their own biases in their review by looking only at the funding sources and not judging the research on its merits,” the president of the trade group, Susan K. Neely, said in a statement.

The new study looked at research published in scientific journals from 1999 to 2003. Studies of milk, juice and soft drinks were chosen, Dr. Ludwig said, because they deal with a controversial area that involves children and highly profitable products.

Of 206 articles, 111 reported their sponsors. Two investigators with no knowledge of the sponsors, who wrote or published the articles or even the articles’ titles classified their conclusions as favorable, neutral or unfavorable to the industry.

Another investigator, with no knowledge of the articles’ conclusions, determined the financing sources and whether or not the sponsors stood to gain or lose from favorable conclusions.

A study of carbonated beverages in 2003 published in The International Journal of Food Sciences and Nutrition and financed by the American Beverage Association when it was known as the National Soft Drink Association found that boys with high weights did not consume more regular soft drinks than boys who were not overweight but did consume more diet soft drinks.

The soft drink industry has cited the study to bolster its position that soft drinks are not related to obesity.

“My co-authors and I rely heavily on scientific method in order to make sure we do not have bias in our studies,” said Richard A. Forshee, the lead author of that study and deputy director at the Center for Food, Nutrition and Agriculture Policy at the University of Maryland.

Also in 2003, a study of soft drinks in The Archives of Pediatrics and Adolescent Medicine found a direct relationship between the number of soft drinks consumed and obesity. Foundations sponsored that study.

“For people who think science is completely objective, these results might come as a big shock,” said Prof. Marion Nestle of the Nutrition, Food Studies and Public Health Department at New York University.

photo by: cdgabinete, Ferney Voltaire, August 2005