Study Takes Bite Out of Media Claims about Low-Fat Diets
A new, larger-sample study refutes previous report linking diet to cancer prevention.

By Ken Shepherd
Free Market Project
Feb. 8, 2006

     After nine months of reporters such as NBC’s Katie Couric prodding women to eat low-fat diets to prevent breast cancer, a new government study argues the hype was for nothing. Low-fat diets don’t ward off breast cancer or heart disease, as was previously suspected.

     The broadcast news media mentioned the original study by the National Cancer Institute (NCI) roughly 20 times in the months following its May 17, 2005 release, according to a review of Nexis transcripts by the Free Market Project.

     In one such occasion, NBC’s Katie Couric told viewers on the Sep. 28, 2005 “Today” show that even if the study was later refuted, it’s never a bad idea for women to maintain a low-fat diet to ward off heart problems.

     “In terms of heart disease and so many other potential maladies, it's much better to eat a diet that's low in fat. But low-calorie, low-fat usually goes hand in hand, right,” NBC’s “Today” show host asked Dr. Clifford Hudis of Memorial Sloan-Kettering Cancer Center. Hudis agreed, “That's right. So one of the easier ways to achieve a low-calorie diet is to limit fats. And for that, we – we continue to push that.”

     The study Couric and Hudis referred to examined less than 2,500 women over five years before reaching its conclusion that the tentative conclusion that results “demonstrate the possible importance of considering dietary factors in cancer therapy trials.”

     But the February 8 editions of The New York Times and The Washington Post ran front-page reports showing that an eight-year, nearly 49,000-woman survey conducted by the National Heart, Lung and Blood Institute (NHLBI) found no benefit in preventing cancer, stroke, or heart disease from a low-fat diet.

     “We set out to test a promising but unproven hypothesis that has proven to be less promising than we anticipated,” NHLBI’s Dr. Jacques Rossouw told the Post. “Based on our findings, we cannot recommend that most women should follow a low-fat diet.”

     The New York Times’s Gina Kolata ended her February 8 story with a warning to scientists not to hype isolated studies. “We, in the scientific community, often give strong advice based on flimsy evidence,” Kolata quoted UC Berkeley statistician David Freedman, “That's why we have to do experiments.”

     The media would also do well to heed Freedman’s advice on complicated, often contradictory studies in nutrition, rather than hype results and make broad generalizations.

     The media’s push for low-fat foods is often coupled with hype over unhealthy eating in America. The Free Market Project has previously issued studies on the media’s unbalanced coverage of American obesity.