ROCHESTER, Minn. — An Iowa State University professor challenged the idea that dietary fat is bad in his presentation at the Southeast Minnesota Ag Alliance annual meeting.
Lance Baumgard, an associate professor in the Department of Animal Science at Iowa State University, said Americans are inundated with messages that fats are bad for them. But how did the animal fat is bad hypothesis come to be accepted?
Back in 1952, University of Minnesota professor Ancel Keys said fat should represent less than 30 percent of calories in a person’s diet. His theory was that eating saturated fat increases cholesterol, which clogs arteries and causes heart attacks and death.
Baumgard doesn’t trivialize heart disease, saying coronary heart disease is the leading cause of adult death in industrialized countries. In 2002, 28 percent of deaths in the United States were due to heart disease.
He just questions whether dietary fat has anything to do with it.
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Is it what Americans eat or their lack of exercise that’s causing heart disease?
"We’re definitely getting heavier," Baumgard said. The United States is leading the way among other Western countries with 30 percent of the population considered obese, he said.
Americans have also become more sedentary. His grandfather did more physical labor before 8 a.m. than he does in a day, Baumgard said.
But the focus has been on what’s eaten. It was Sen. George McGovern’s staff who changed national policy and initiated the process of turning Keys’ dietary fat hypothesis into dogma, Baumgard said.
The USDA food guide, which has been around in some form since 1917, was changed in 1977 to reflect Keys’ theory. Americans were told to reduce their fat intake, especially saturated fat, and increase their intake of carbohydrates.
Where does saturated fat come from? Dairy, beef and other animal products are commonly associated with saturated fat, Baumgard said. The recommendation boils down to eat less meat and more vegetables.
The message is still in the food pyramid. In the 2000 dietary guidelines for Americans, it’s recommended that people choose a diet that is low in saturated fat and cholesterol and moderate in total fat.
"We’re just incredibly scared of fat as a country," Baumgard said.
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Magazines, especially those targeted to women, are loaded with messages that dietary fat is bad, Baumgard said, showing slide after slide of magazine covers at the Jan. 17 meeting.
His mother read the magazines, he said. She went from whole milk to 2 percent to 1 percent and down to skim. He thinks she is listening to him because she’s back up to 1 percent.
"The people who buy the groceries — typically that’s the mother — are doing what they think is best for their family," he said.
Baumgard also challenges the theory that blood cholesterol levels can be altered based on diet. He cited papers that support his theory.
Don’t stop taking cholesterol-lowering drugs, he advised the members of the audience, but realize that cholesterol-lowering drugs are a multi-billion dollar industry. Be aware there is disagreement in the scientific community and talk to your doctor about it.
His point is that few people have heard of experiments that contradict the accepted benefit of a low-fat diet.
If a study comes out that contradicts accepted dogma, Baumgard said it’s disputed. An example is the Women’s Health Initiative. The study involved 160,000 women ages 50 to 79. One group was allowed to eat whatever they wanted while the other was put on a low-fat diet. The study lasted eight years and cost U.S. taxpayers $700 million.
According to a February 2006 article in the Journal of the American Medical Association, the low-fat diet pattern didn’t reduce the occurrence of breast cancer, coronary heart disease, colorectal cancer, stroke or cardiovascular disease.
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The most expensive nutrition study ever done by the U.S. government failed to change attitudes, Baumgard said.
He wonders if the anti-fat campaign is so strong because of profits made from the sale of health foods and diet pills, plans and books. He wonders if animal rights groups are involved.
People for the Ethical Treatment of Animals has been in a large part unsuccessful in convincing Americans to adopt a vegetarian lifestyle for moral or ethical reasons, so they are going for the health angle, he said, but he’s got no way to connect PETA to the message.
His goal is to get people to realize that there’s conflict. There’s little evidence to suggest saturated fat is harmful in diets. It’s not a cut-and-dry dogma, Baumgard said.
Increasingly, scientists are willing to challenge the accepted dogma, he said.
Baumgard, who has followed the topic for nearly a decade, suggests people eat a balanced diet, exercise and maintain a healthy weight.
