Nutritional case against whole milk thins

Washington Post

U.S. dietary guidelines long have recommended people steer clear of whole milk. For decades, Americans obeyed. Consumption of whole milk shrank. It was banned from school lunch programs. Sales of low-fat dairy climbed.

'Replace whole milk and full-fat milk products with fat-free or low-fat choices,” says the Dietary Guidelines for Americans, the government's influential advice book, citing the role of dairy fat in heart disease.

Whether this massive shift in eating habits has made anyone healthier is an open question. Research in recent years indicates the opposite may be true: Millions might be better off had they stuck with whole milk.

This year, as the Dietary Guidelines for Americans undergoes an update, the bureaucrats writing them must confront what may be the most controversial question in nutrition: Does consumption of saturated fats -- characteristic of meat and dairy products - contribute to heart disease?

There are about 1,400 dairy farms with more than 200,000 milk cows in Iowa, according to the Iowa State Dairy Association, making it 12th in the nation in pounds of milk produced annually. One job is created for every 10 milk cows, the industry group says.

In the United States, heart disease is the leading cause of death and the government has long blamed saturated fats.

But the idea that spurning saturated fat will, by itself, make people healthier has never been fully proved.

Scientists who tallied diet and health records for several thousand patients over 10 years found that contrary to the government advice, people who drank more milk fat had lower incidence of heart disease.

By warning people against full-fat dairy foods, the United States is 'losing a huge opportunity for the prevention of disease,” said Marcia Otto, an assistant professor of epidemiology at the University of Texas and the lead author of large studies published in 2012 and 2013, which were funded by government and academia, not the dairy industry. 'What we have learned over the last decade is that certain foods that are high in fat seem to be beneficial.”

After all the research, the key lesson possibly is twofold. Cutting saturated fat from diets and replacing them with carbohydrates, as is often done, likely will not reduce the risk of heart disease. But replacing them with unsaturated fats - the type of fats characteristic of fish, nuts and vegetable oils - might.

The shift in evidence has led to accusations that the Dietary Guidelines harmed those people who for years avoided fats, as instructed, and loaded up excessively on the carbohydrates in foods such as breads, cookies and cakes marketed as low-fat.

The government's dietary science has drawn skepticism on Capitol Hill. On Wednesday, a House committee aired concerns over the evidence behind the guidelines with Agriculture Secretary Tom Vilsack and Health and Human Services Secretary Sylvia Mathews Burwell.

The Dietary Guidelines have stepped back slightly from their blanket advice to reduce saturated fats, adding the caveat that saturated fats ought to be replaced with unsaturated fats.

But Dariush Mozaffarian, a cardiologist, epidemiologist and dean of the Friedman School of Nutrition Science and Policy at Tufts University, said that the guidelines have yet to retreat far enough from the idea that saturated fat is a dietary evil, and that the suspicion of whole milk is a good example.

Judging a particular food solely on how much fat it contains, he said, can too easily blind people to its other benefits.

'If we are going to make recommendations to the public about what to eat, we should be pretty darn sure they're right and won't cause harm,” Mozaffarian said.

Some, including representatives of the American Heart Association, disagree. In their view, evidence for the dangers of saturated fats arises from these ideas: Consuming saturated fats raises levels of 'bad” cholesterol in the blood and higher levels of bad cholesterol, in turn, raise risks of heart disease.

They point to trials of statin drugs, which show that the drugs lower bad cholesterol levels and risks of heart disease.

There is a 'mountain of evidence” on how consumption of saturated fats raises the risk of heart disease, said Penny Kris-Etherton, a nutrition professor at Pennsylvania State University and a former member of the Dietary Guidelines advisory committee.

But if nothing else. decades of research indicates that the warning against saturated fats was too simplistic.

By itself, cutting saturated fats appears to do little to reduce heart disease. Several reviews, summing up years of research and appearing in leading academic publications including the American Journal of Clinical Nutrition, the Annals of Internal Medicine and the British Medical Journal, found no significant evidence of a link between heart disease and saturated fats.

The 'campaign to reduce fat in the diet has had some pretty disastrous consequences,” Walter Willett, dean of the nutrition department at the Harvard School of Public Health, has said. 'With more fat-free products than ever, Americans got fatter.”