Frequently when I discuss issues of science as they
relate to faith, I'm often told that science shouldn't be doubted. After all,
science, unlike faith, isn't about what people want to believe. It only deals in
cold, hard facts, and when science reaches a consensus, like it has with the
modern neo-Darwinian paradigm, it is unreasonable to reject it. Rejecting the
scientific beliefs of the vast majority of scientists is equal to denying that
the earth is round.
That's the story, but that isn't science.
It's scientism. Fundamental to science is the concept of questioning the
facts we think we know, even what can be considered well-established facts.
Newton's laws were thought to hold in all applications for centuries until
quantum mechanics came along and threw a fly in the ointment. Other assumptions,
such as the steady state model for the universe, have also been upended.
But
many of those ideas are too esoteric for the average man on the street to really
grasp. However, there is currently a paradigm shift happening in the health
sciences that perfectly illustrates how accepted science can be flimsy, biased,
and based not on facts but strong wills and politics. The story is fascinating
and illustrates how just one man can create a belief that is so strong, it
affects the viewpoint other experts, changes government regulations, and becomes
an embedded belief by the general population.
In her article "The science of
saturated fat: A big fat surprise about nutrition?" author Nina Teicholz
summarizes her findings of a nine year investigation into the commonly-accepted
belief that the more saturated fats you eat, the worse it is for your heart.
I recommend you read the
entire article, or if you would like even more detail, grab her
well-documented book
The Big
Fat Surprise: Why Butter, Meat, and Cheese Belong in a Healthy Diet. However,
here are a few quotes of how the myth of the unhealthy high fat diets became the
unquestioned standard:
1. One man's
assumption led to bad conclusions
Teicholz writes that the idea to link
saturated fats to heart disease was proposed by Ancel Keys, a pathologist who
was "an aggressive, outsized personality with a talent for persuasion."
1
Keys' studies on this link "violated several basic scientific norms,"
2
according to Teicholz. For example, Key's findings were based on a single
study, claiming to look at the diets of some 13,000 men across seven countries.
However, Teicholz reports that Keys did not select random nations, but only
those that supported his hypothesis, and he ignored others. She writes there
were other problems with the study as well:
Due to difficulties in
collecting accurate nutrition data, Keys ended up sampling the diets of fewer
than 500 men, far from a statistically significant sample. And the study's star
subjects — men on the Greek island of Crete who tilled their fields well into
old age and appeared to eat very little meat or cheese — turned out to have been
partly sampled during Lent, when the study subjects were foregoing meat and
cheese. This must have led Keys to undercount their saturated-fat consumption.
These flaws weren't revealed until much later. By then, the misimpression left
by the erroneous data had become international dogma.3
2. One man's push led to accepted dogma
The second factor that led to the widespread acceptance of Keys views was a
combination of good timing and Keys' dominant personality. Teicholz
reports:
He found a receptive audience for his "diet-heart hypothesis"
among public-health experts who faced a growing emergency: heart disease, a
relative rarity three decades earlier, had skyrocketed to be a leading cause of
death. Keys managed to implant his idea into the American Heart Association and,
in 1961, the group published the first-ever guidelines calling for Americans to
cut back on saturated fats, as the best way to fight heart disease. The US
government adopted this view in 1977 and the rest of the world followed.4
Once the idea became ingrained, it became a foregone conclusion.
There were
subsequent trials, of course. In the 1970s, half a dozen important experiments
pitted a diet high in vegetable oil — usually corn or soybean, but not olive oil
— against one with more animal fats. But these trials had serious methodological
problems: some didn't control for smoking, for instance, or allowed men to
wander in and out of the research group over the course of the experiment. The
results were unreliable at best…
When Ronald M Krauss decided, in 2000, to
review all the evidence purporting to show that saturated fats cause heart
disease, he knew that he was putting his professional career at risk. Krauss is
one of the top nutrition experts in the United States, director of
atherosclerosis research at Children's Hospital Oakland Research Institute and
adjunct professor of nutritional studies at the University of San Francisco at
Berkley. But challenging one of his field's most sacrosanct beliefs was a
near-heretical act.
Challenging any of the conventional wisdom on
dietary fat has long been a form of professional suicide for nutrition experts.
And saturated fats, especially, are the third rail.
3.
The power of intimidation affects consensus
Finally, Teicholz states that
Keys himself was not as interested in advancing the science as he was in keeping
his findings in the center of belief. He would belittle and mock those who would
oppose his theory:
Keys aggressively criticised these observations, which were like missiles
aimed at the very heart of his theory… In response to a prominent Texas A&M
University professor who wrote a critique of Keys, he said that the paper
"reminds one of the distorting mirrors in the hall of jokes at the county fair".
Rolling over the opposition by sheer force of will was typical of Keys and his
acolytes in defending their saturated-fat hypothesis. Keys was "tough and
ruthless and would argue any point", Oliver, a prominent opponent, said. Since
Keys's allies controlled so many top government health posts, critics were
denied research grants and key posts on expert panels. As retribution for
defending the healthiness of eggs, despite their cholesterol content, Oliver was
publicly branded by two of Keys's main allies as a "notorious type" and a
"scoundrel" because "he opposed us on everything".
In the end, Keys and his
colleagues prevailed. Despite contrary observations from India to the Arctic,
too much institutional energy and research money had already been spent trying
to prove Keys's hypothesis. The bias in its favour had grown so strong that the
idea just started to seem like common sense.5
The
parallels between this and modern paradigms like global climate change or
neo-Darwinian synthesis are striking. Each was formed at the right time by
those looking to dismiss a creator or in a time of significant environmental
sensitivity. Each has had high-profile proponents. Each has claimed the
scientific high ground to the degree that any deviation from the accepted
consensus would be mocked and belittled, and considered professional suicide.
Many good scientists would speak authoritatively on the saturated fat-heart
disease link, even today. However, the consumer needs to be more dubious of any
connection between the two. While many Keys's critics gained some clout by
having a well-respected journal (the
Lancet and the
British
Medical Journal) willing to publish their work, and thus began to crack the
saturated fat myth,
one wonders how long it would have persisted if the British medical
professionals had not investigated the claims.
The tale of saturated fat and
Ancel Keys should serve as a warning to those who claim that "consensus"
and "accepted science" are good enough to keep scientific claims from being
questioned. They show exactly the opposite. After all, scientists are people,
and people are prone to be biased. So, don't accept the tale that science is
above reproach. It can be a flawed belief system, too.
References
At any given time, scientists should infer the best current explanation of the available
