PLEASE, LET HIM BE RIGHT AGAIN...:

In 1957, a fledgling nutrition scientist at the University of Illinois persuaded a hospital to give him samples of arteries from patients who had died of heart attacks.

When he analyzed them, he made a startling discovery. Not surprisingly, the diseased arteries were filled with fat -- but it was a specific kind of fat. The artificial fatty acids called trans fats, which come from the hydrogen-treated oils used in processed foods like margarine, had crowded out other types of fatty acids.

The scientist, Fred Kummerow, followed up with a study that found troubling amounts of artery-clogging plaque in pigs given a diet heavy in artificial fats. He became a pioneer of trans-fat research, one of the first scientists to assert a link between heart disease and processed foods. [...]

In the past two years, he has published four papers in peer-reviewed scientific journals, two of them devoted to another major culprit he has singled out as responsible for atherosclerosis, or the hardening of the arteries: an excess of polyunsaturated vegetable oils like soybean, corn and sunflower -- exactly the types of fats Americans have been urged to consume for the past several decades.

The problem, he says, is not LDL, the "bad cholesterol" widely considered to be the major cause of heart disease. What matters is whether the cholesterol and fat residing in those LDL particles have been oxidized. (Technically, LDL is not cholesterol, but particles containing cholesterol, along with fatty acids and protein.)

"Cholesterol has nothing to do with heart disease, except if it's oxidized," Dr. Kummerow said. Oxidation is a chemical process that happens widely in the body, contributing to aging and the development of degenerative and chronic diseases. Dr. Kummerow contends that the high temperatures used in commercial frying cause inherently unstable polyunsaturated oils to oxidize, and that these oxidized fatty acids become a destructive part of LDL particles. Even when not oxidized by frying, soybean and corn oils can oxidize inside the body.

If true, the hypothesis might explain why studies have found that half of all heart disease patients have normal or low levels of LDL.

"You can have fine levels of LDL and still be in trouble if a lot of that LDL is oxidized," Dr. Kummerow said.

This leads him to a controversial conclusion: that the saturated fat in butter, cheese and meats does not contribute to the clogging of arteries -- and in fact is beneficial in moderate amounts in the context of a healthy diet (lots of fruits, vegetables, whole grains and other fresh, unprocessed foods).

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