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Saturday, November 25, 2017

Myth Buster: Saturated Fat Causes Heart Disease

When it comes to medicine we have to be careful what we read. This is particularly true when it comes to conventional wisdom, especially when something is said without citation. Something like, "High-fat foods may cause weight gain and heart disease."

We are fed a barrage of information about fatty foods causing weight gain and heart disease. Seldom is there a reference supporting this. It's just said as though it were a fact, similar to the one that says, "Humans are causing global warming."

Evidence, please?

At least with global warming, it's computer moderated information. What they don't tell you is that the information that comes out is only as good as what comes it. So, if what goes in is junk, what comes out is junk. But, when it comes to fatty foods causing weight gain and heart disease, there's no evidence to be heard from.

In this case, it seems that someone just made this up because it sounds good. Then everyone else just kind of went with it. Then it becomes conventional wisdom. And it's thought to be a fact. When in fact it's just a myth.

A few years ago I wrote a good article on this blog. It was called "Myth Busted: Junk Food Doesn't Cause Heart Disease." So true I turned out to be. Nina Teicholz discussed this in the Wall Street Journal in her article: "The Questionable Link Between Saturated Fat and Heart Disease."

She said the myth was started by one person by the name of Ancel Keys. This lead to a 50-year campaign to convince people not to eat meat, eggs, and whole fat dairy.  Despite this campaign, there has never been one scientific piece of evidence to show this to be true. 

She said:
"Saturated fat does not cause heart disease"—or so concluded a big study published in March in the journal Annals of Internal Medicine. How could this be? The very cornerstone of dietary advice for generations has been that the saturated fats in butter, cheese and red meat should be avoided because they clog our arteries. For many diet-conscious Americans, it is simply second nature to opt for chicken over sirloin, canola oil over butter.
The new study's conclusion shouldn't surprise anyone familiar with modern nutritional science, however. The fact is, there has never been solid evidence for the idea that these fats cause disease. We only believe this to be the case because nutrition policy has been derailed over the past half-century by a mixture of personal ambition, bad science, politics and bias.
She provides us with the history of the myth.
Our distrust of saturated fat can be traced back to the 1950s, to a man named Ancel Benjamin Keys, a scientist at the University of Minnesota. Dr. Keys was formidably persuasive and, through sheer force of will, rose to the top of the nutrition world—even gracing the cover of Time magazine—for relentlessly championing the idea that saturated fats raise cholesterol and, as a result, cause heart attacks.
This idea fell on receptive ears because, at the time, Americans faced a fast-growing epidemic. Heart disease, a rarity only three decades earlier, had quickly become the nation's No. 1 killer. Even President Dwight D. Eisenhower suffered a heart attack in 1955. Researchers were desperate for answers.
As the director of the largest nutrition study to date, Dr. Keys was in an excellent position to promote his idea. The "Seven Countries" study that he conducted on nearly 13,000 men in the U.S., Japan and Europe ostensibly demonstrated that heart disease wasn't the inevitable result of aging but could be linked to poor nutrition.
Critics have pointed out that Dr. Keys violated several basic scientific norms in his study. For one, he didn't choose countries randomly but instead selected only those likely to prove his beliefs, including Yugoslavia, Finland and Italy. Excluded were France, land of the famously healthy omelet eater, as well as other countries where people consumed a lot of fat yet didn't suffer from high rates of heart disease, such as Switzerland, Sweden and West Germany. The study's star subjects—upon whom much of our current understanding of the Mediterranean diet is based—were peasants from Crete, islanders who tilled their fields well into old age and who appeared to eat very little meat or cheese.
 As we know, once something becomes established in the medical community, it becomes conventional wisdom. Once something becomes conventional wisdom, it becomes almost impossible to disprove. Global warming is a perfect example of this. Now, it appears, that saturated fat is another.

But, don't worry. The American Heart Association still lists Saturated fat as a big no-no. No citation. I'm not criticising the AHA here because they do lots of good things. I'm just saying, it's so easy to become a victim of a myth.

And, besides. Modern evidence does show that only some people have heart disease genes. So, it would seem to me that a better thing to teach is, "If you have a family history of heart disease, you might want to be careful with high-fat foods and cholesterol."

But that's not how we are in this world. We continue to repeat myths long after they have been disproven. Hypoxic Drive Hoax anyone?

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