Does saturated fats clog your arteries? Controversial paper says 'no'
4/26/2017, 6 a.m.
(CNN) It is common knowledge supported by health experts, the American Heart Association and the World Heart Federation: Eating saturated fats will cause plaque to build up in the arteries, which then harden, and ultimately leads to coronary heart disease. To prevent heart disease, the association and federation both recommend a diet low in saturated fats, the animal-based fats found in beef, pork, chicken, butter and cheese, among other foods.
But in an editorial published Tuesday in the British Journal of Sports Medicine, three cardiologists say saturated fats do not clog arteries and the "clogged pipe" model of heart disease is "plain wrong."
The authors write that eating saturated fats is not associated with either coronary heart disease, ischemic stroke, type 2 diabetes, death from heart disease or early death in healthy adults, referencing a meta-analysis, or review of previous studies, to support their claims. Critics of the editorial noted that the meta-analysis is based on observational data, and is not considered conclusive by general scientific standards.
"This idea that dietary saturated fats build up in the coronary arteries is complete unscientific nonsense," said Dr. Aseem Malhotra, first author of the new controversial editorial and a consultant cardiologist at London's Lister Hospital, in an email to CNN.
According to Malhotra and his co-authors, Dr. Rita Redberg, a cardiologist at UCSF School of Medicine in San Francisco and Dr. Pascal Meier, a cardiologist at University Hospital Geneva, healthy people can effectively reduce risk of coronary disease by walking 22 minutes a day, minimizing stress and eating "real food."
Saturated fat in itself is not a problem, they say.
Critics question the merits of the editorial noting that it is not based on any new research. Among them, Dr. Mike Knapton, associate medical director at the British Heart Foundation, referred to it as an opinion piece, calling it "unhelpful and misleading." He said in a statement, "decades of research have proved that a diet rich in saturated fat increases 'bad' LDL cholesterol in your blood, which puts you at greater risk of a heart attack or stroke."
As described by the American Heart Association, a heart attack or a stroke can begin when plaque -- cholesterol, fat, cellular waste and other substances -- accumulate in the arteries, effectively "hardening" them, a condition known as atherosclerosis. Wherever plaque builds, two things can occur: a blood clot can form or a piece of the plaque can break off and block the artery.
While many of us believe that cardiac events occur wherever the biggest deposits of plaque are, truth is most events occur where there's less than 70% coronary artery obstruction, the editorial authors said.
"Coronary artery disease is a chronic inflammatory condition," said Malhotra. It is inflammatory processes that contribute to deposits of cholesterol within the artery wall and formation of plaque, he and his co-authors say. Plaques rupture in the manner of a pimple and this is what can cause a heart attack or stroke.
Coronary disease does not resemble a "clogged pipe," they say. Evidence of this, they say, is contained in a series of studies which found that using stents to open arteries narrowed by plaque fails to prevent heart attack or reduce mortality.