The group’s finding that cholesterol in the diet need no longer be considered a “nutrient of concern” stands in contrast to the committee’s findings five years ago, the last time it convened. During those proceedings, as in previous years, the panel deemed the issue of excess cholesterol in the American diet a public health concern.
The finding follows an evolution of thinking among many nutritionists who now believe that, for healthy adults, eating foods high in cholesterol may not significantly affect the level of cholesterol in the blood or increase the risk of heart disease.
The greater danger in this regard, these experts believe, lies not in products such as eggs, shrimp or lobster, which are high in cholesterol, but in too many servings of foods heavy with saturated fats, such as fatty meats, whole milk, and butter.
The new view on cholesterol in food does not reverse warnings about high levels of “bad” cholesterol in the blood, which have been linked to heart disease. Moreover, some experts warned that people with particular health problems, such as diabetes, should continue to avoid cholesterol-rich diets.
While Americans may be accustomed to conflicting dietary advice, the change on cholesterol comes from the influential Dietary Guidelines Advisory Committee, the group that provides the scientific basis for the “Dietary Guidelines.” That federal publication has broad effects on the American diet, helping to determine the content of school lunches, affecting how food manufacturers advertise their wares, and serving as the foundation for reams of diet advice.
The panel laid out the cholesterol decision in December, at its last meeting before it writes a report that will serve as the basis for the next version of the guidelines. A video of the meeting was later posted online and a person with direct knowledge of the proceedings said the cholesterol finding would make it to the group’s final report, which is due within weeks.
After Marian Neuhouser, chair of the relevant subcommittee, announced the decision to the panel at the December meeting, one panelist appeared to bridle.
“So we’re not making a [cholesterol] recommendation?” panel member Miriam Nelson, a Tufts University professor, said at the meeting as if trying to absorb the thought. “Okay ... Bummer.”
Members of the panel, called the Dietary Guidelines Advisory Committee, said they would not comment until the publication of their report, which will be filed with the Department of Health and Human Services and the Department of Agriculture.
While those agencies could ignore the committee’s recommendations, major deviations are not common, experts said.
Five years ago, “I don’t think the Dietary Guidelines diverged from the committee’s report,” said Naomi K. Fukagawa, a University of Vermont professor who served as the committee’s vice chair in 2010. Fukagawa said she supports the change on cholesterol.
Walter Willett, chair of the nutrition department at the Harvard School of Public Health, also called the turnaround on cholesterol a “reasonable move.”
“There’s been a shift of thinking,” he said.
But the change on dietary cholesterol also shows how the complexity of nutrition science and the lack of definitive research can contribute to confusion for Americans who, while seeking guidance on what to eat, often find themselves afloat in conflicting advice.
Cholesterol has been a fixture in dietary warnings in the United States at least since 1961, when it appeared in guidelines developed by the American Heart Association. Later adopted by the federal government, such warnings helped shift eating habits -- per capita egg consumption dropped about 30 percent -- and harmed egg farmers.
Yet even today, after more than a century of scientific inquiry, scientists are divided.
Some nutritionists said lifting the cholesterol warning is long overdue, noting that the United States is out-of-step with other countries, where diet guidelines do not single out cholesterol. Others support maintaining a warning.
The forthcoming version of the Dietary Guidelines -- the document is revised every five years -- is expected to navigate myriad similar controversies. Among them: salt, red meat, sugar, saturated fats and the latest darling of food-makers, Omega-3s.
As with cholesterol, the dietary panel’s advice on these issues will be used by the federal bureaucrats to draft the new guidelines, which offer Americans clear instructions -- and sometimes very specific, down-to-the-milligram prescriptions. But such precision can mask sometimes tumultuous debates about nutrition.
“Almost every single nutrient imaginable has peer reviewed publications associating it with almost any outcome,” John P.A. Ioannidis, a professor of medicine and statistics at Stanford and one of the harshest critics of nutritional science, has written. “In this literature of epidemic proportions, how many results are correct?”
Now comes the shift on cholesterol.