Read The Great Cholesterol Myth Online
Authors: Jonny Bowden
When the National Cholesterol Education Program lowered the “optimal” cholesterol levels in 2004, eight out of nine people on the panel had financial ties to the pharmaceutical industry.
Besides the fact that you’re concerned about your cholesterol, there are two other things we can assume. One, you don’t tend to blindly follow recommendations without doing your own research. (If you did, you’d simply be following your doctor’s orders and have no interest in reading this book.)
The second thing we’re pretty sure about you is that you’re smarter than the average reader.
Here’s why:
To understand the cholesterol myth—and to fully appreciate how the health advice that follows from the myth is obsolete—you’ll need to know a lot more about cholesterol than the average person knows. But reading—and understanding—the full story of cholesterol, including the myths, misconceptions, outright lies, and misguided medical practices, doesn’t make for easy reading. It’ll take quite a bit more intelligence, motivation, and perseverance than, say, reading the latest romance paperback.
The cholesterol story touches on not only medicine and research but also politics, economics, psychology, and sociology. It’s got a cast of characters ranging from the obnoxious and egotistical to the well-meaning and misguided.
It has heroes and villains, mavericks and traditionalists, all engaged in a battle that, sadly, has little to do with saving lives (though it may have started out that way). It involves staggering amounts of money, the politics of publication, the sociology of belief (why bad ideas continue to survive past their expiration dates), and the revolving door that exists between government advisory committees and the industries they’re supposed to police. (Example: When the National Cholesterol Education Program lowered the “optimal” cholesterol levels in 2004, eight out of nine people on the panel had financial ties to the pharmaceutical industry, most of them to the manufacturers of cholesterol-lowering drugs who would subsequently reap immediate benefits from these same recommendations.)
By now it should be pretty clear that neither of us buys into the myth that cholesterol is the proper target for the prevention of heart disease. But how did the myth get started in the first place? How, exactly, did cholesterol and saturated fat come to be branded as the twin demons of heart disease?
To answer that question, we need to go back to 1953, when a young, ambitious biologist named Ancel Keys proposed the then-radical theory that heart disease was caused by too much fat in the diet.
It’s hard to imagine that this theory was radical given how widespread its acceptance is today, but at the time the prevailing wisdom was that diet had little to do with heart disease. But Keys felt he was on to something.
Previous research by Russian scientists had shown that when you fed rabbits large amounts of cholesterol and then dissected them later on, their arteries were filled with cholesterol-containing plaque and looked suspiciously like the arteries of people who died of heart disease. Never mind the inconvenient fact that rabbits are herbivores. The amount of cholesterol they normally get in their diets is pretty close to zero. Other animals, such as rats and baboons, do
not
react in the same way as rabbits to a high-cholesterol diet, and they metabolize cholesterol very differently. Even Keys himself understood that cholesterol in the diet was of no importance. In 1997, he stated, “There’s no connection whatsoever between cholesterol in food and cholesterol in blood. And we’ve known that all along. Cholesterol in the diet doesn’t matter at all unless you happen to be a chicken or a rabbit.”
Yet the admonition to eat “no more than 300 mg of cholesterol” a day remains the advice of every major health organization to this day, despite the fact that even the scientist most responsible for popularizing the diet–heart hypothesis thought it was ridiculous.
Inconvenient facts to the contrary, excess cholesterol in the
blood
, not the diet, seemed to Keys to be a likely culprit in the development of heart disease.
Since fat in the diet and cholesterol in the blood were believed to be linked, this led Keys to investigate fat in the diet and its connection to heart disease. He looked at data on fat consumption and heart disease from various countries and published the results of his famous study, the Seven Countries Study, which supposedly demonstrated a clear link between the amount of dietary fat consumed and the incidence of heart disease. Those countries eating the most fat also had the highest rates of heart disease. Sounds like an open-and-shut case against dietary fat, doesn’t it?
Except it was anything but. When Keys published the results of his study, he actually had available to him reliable food consumption data from twenty-two countries, but he used only seven. By hand-selecting the seven countries that supported his preconceived hypothesis, Keys was able to make a convincing case that there was a direct connection between dietary fat and heart disease.
The fact that Keys had chosen to include only seven countries and ignored the other fifteen didn’t exactly go unnoticed. Many researchers criticized Keys for conveniently omitting data that didn’t support his theory. Researchers analyzing the data from all twenty-two countries found that the correlation between fat, cholesterol, and heart disease literally vanished.
One of the researchers who questioned Keys was a British doctor named John Yudkin from the University of London. He found that there were countries where the intake of fat was virtually the same, but the rates of cardiovascular disease were vastly different. For example, Finland was one of the
countries used by Keys to make his case, because Finland had a high per capita fat intake and a high rate of heart disease. But Yudkin found that the people of West Germany ate the exact same amount of fat as the people of Finland, but they had about one-third the rate of heart disease. The paradox was even more pronounced in the Netherlands and Switzerland, which also had only one-third the rate of heart disease seen in Finland, even though the Dutch and Swedes consumed even
more
fat than the Finns.
Yudkin’s much more comprehensive data showed that the single dietary factor that had the strongest association with coronary heart disease was—wait for it—
sugar
.
Yudkin did a far more extensive analysis of dietary factors than Keys did. He looked at fat as a percentage of calories. He looked at different types of fats. He even looked at the roles of carbohydrates and protein. And instead of confirming Keys’s hypothesis, Yudkin’s much more comprehensive data showed that the single dietary factor that had the strongest association with coronary heart disease was—wait for it—
sugar
.
So back to Keys. By all accounts, Keys was a very smart and well-liked man who just happened to be dead wrong on the cholesterol and fat issue. But he was hardly without ambition and ego. Known for being blunt and biting, he presented his theory on fat, cholesterol, and heart disease to a distinguished audience in 1954, when the World Health Organization (WHO) held its first expert committee on the pathogenesis of atherosclerosis. One of his longtime collaborators, Henry Blackburn, recalled that Keys was stunned to find that his ideas were not accepted on the spot. One participant asked him to cite the principle piece of evidence for his diet–heart theory, and he was caught, to put it mildly, off guard. “Ancel fell into a trap, he made a mistake,” Blackburn said. “He cited a piece of evidence, and they were able to destroy it. He got up from being knocked to the ground and went out saying, ‘I’ll show those guys,’ and designed the Seven Countries Study.”
3
The Seven Countries Study
4
is actually the cornerstone of current cholesterol and fat recommendations and official government policy, so it’s worth looking at in some detail. Keys examined saturated fat consumption in seven countries, and, lo and behold, he found a straight-line relationship between heart disease, cholesterol levels, and saturated fat intake—exactly what he had hoped to find.
The seven countries were Italy, Greece, the former Yugoslavia, the Netherlands, Finland, the United States, and Japan. It hardly went unnoticed that Keys chose only the countries that fit his hypothesis. He easily could have chosen a different group of countries and proven a completely different hypothesis.
In fact, British physician Malcolm Kendrick, M.D., did exactly that. Kendrick used the same data available to Keys and quickly discovered that if you simply chose different countries, you could easily prove that the
more
saturated fat and cholesterol people consumed, the
lower
their risk of heart disease.
5
Anticipating a challenge to his “proof” by defenders of the cholesterol hypothesis, Kendrick pointed out that he was merely doing exactly what Keys did—hand-selecting data that would prove his theory. “What do you mean I can’t choose my own countries?” he asked sarcastically. “That’s not fair. Keys did!”
6
Cherry-picking the countries that proved this theory was only one of the many problems with the Seven Countries Study. There were tremendous variations in heart mortality within these countries, even though saturated fat consumption was identical. In Finland, for example, the intake of saturated fat was almost identical in two population groups from Turku and North Karelia. But heart mortality was three times higher in North Karelia. Similarly, saturated fat intake was also equal on two Greek islands, Crete and Corfu. But heart mortality was a whopping seventeen times higher on Corfu than it was on Crete.
7
How did Keys explain these facts, which were clearly present in his data?
Simple. He ignored them.
Keys was a member of the nutrition advisory committee of the American Heart Association, so despite the flaws in his study, he managed to get his theories officially incorporated into the 1961 American Heart Association dietary guidelines,
8
where they have influenced government policy on heart disease, fat consumption, and cholesterol for decades.
At the time, Keys’s theories about fat and cholesterol weren’t exactly widely known outside scientific circles, and the whole theoretical fight between the advocates of the “sugar” hypothesis and the advocates of the “fat” hypothesis was all so much ivory-tower name-calling, well out of the earshot of the general public. But all that was about to change.
And the man who was indirectly responsible for that change was, interestingly, not a scientist at all but a politician named George McGovern.
McGovern, chairman of the Senate Select Committee on Nutrition and Human Needs, practically changed the national policy on nutrition in this country. And they were directly responsible for transforming the idea that dietary fat causes heart disease from a not-so-solid hypothesis into solidified dogma.
McGovern’s committee instituted a wonderful series of landmark federal food assistance programs, but its work on malnutrition started to wind down around the mid-1970s. McGovern’s committee staffers, notably its general counsel, Marshall Matz, and staff director, Alan Stone, both lawyers, decided to go for broke and take on the reverse side of the malnutrition coin:
over
nutrition. “It was a casual endeavor,” Matz said. “We really were totally naive, a bunch of kids who just thought, ‘Hell, we should say something on this subject before we go out of business.’ ”
9
The committee listened to two days of expert testimony in 1976 and then assigned a young writer
named Nick Mottern to write the whole thing up. The only problem was that Mottern didn’t know anything about nutrition and health and had no science writing background to boot. So he did what any smart young writer would do: He went to the experts for guidance.
WHAT YOU NEED TO KNOW
• The theory that fat and cholesterol cause heart disease became widely accepted
despite
much evidence to the contrary. This evidence deserves to be reexamined. The case needs to be reopened.
• Many doctors did
not
agree with the cholesterol myth and questioned the science upon which it was based.
• The studies upon which the cholesterol myth was based were later found to be problematic.
• The adoption of the cholesterol myth by mainstream organizations and the government had a strong political component to it.
Except in this case, Mottern didn’t actually go to the “experts”; he went to one
particular
expert, Mark Hegsted, a Harvard nutritionist, and relied almost exclusively on Hegsted’s interpretation of the testimony, as well as on Hegsted’s own personal recommendations.
Hegsted was a fervent believer in the emerging theory that low-fat diets would prevent heart disease and that fat and cholesterol were the spawn of Satan.
Whoops.
So Mottern wrote up the committee’s recommendations with Hegsted as the final authority—no more than 30 percent of calories from fat, no more than 10 percent of calories from saturated fat—and in 1977 the committee disbanded. But right around that time, a newly appointed assistant secretary at the U.S. Department of Agriculture (USDA) named Carol Tucker Foreman decided that the USDA ought to
do
something with these recommendations. Like make them official policy! The only problem was that she needed some good scientific cover.