Sunday, August 3, 2014

The Dubious Merits of Scientific Consensus



I recently got into a discussion on facebook regarding the safety of GMOs, which quickly (and perhaps somewhat predictably) devolved into a pointless argument.  I was primarily talking with two musicians, friends of a friend, who insisted that the overwhelming scientific consensus on GMOs was that they were safe and there was really no room for conversation on the subject.  I was told that the question of GMO safety boils down to ”whether you accept the validity of scientific consensus or whether you're plugged into one of the AltMed quasi-cults.  All this from a musician!  (I should mention for any who don’t know that I’m a nutrition student.)  I like musicians, and I like music, but I don’t usually seek out musicians’ professional opinions on health-related questions. 

Arguably one of the biggest take-home messages I’ve received from studying nutrition so far is that the human body is extremely complicated.  Everyone is different and each person is different depending on time of day, what they just ate, and a hundred other factors.  Anybody who’s ever studied organic chemistry can attest to how complex the human body and metabolic pathways are.  It’s appealing to think that when you eat 8oz of broccoli, predictable and consistent effects on the body will occur for everyone.  It’s appealing, but it’s just not true.  The human body is made up of complex, sophisticated mechanisms that take significant study to understand.  And it’s really a beautiful thing, because these mechanisms serve to protect the body in a multitude of circumstances.

This brings me back to the arrogant musicians on facebook.  There is a false sense of being objective, scientific, and knowledgeable that comes from blindly accepting the majority opinion.  One of these guys argued that it would be illogical for him to stray from the “scientific consensus” opinion that GMOs are safe because, as he is a layman in this subject, all he can do is listen to what experts say.  Funny that being a layman doesn’t also preclude him from telling me, someone who is actually studying the subject, that I’m wrong before even hearing my arguments.  Even if GMOs are safe, I still say that his logic is flawed:

It’s not unscientific to disagree with the majority opinion if you’ve studied the subject and reached a differing conclusion that you can back up.  In fact, I would argue that this kind of dissent embodies what science is at its core.  However, agreeing with the majority opinion simply because it is the majority opinion makes one a blind follower with no understanding of the subject, and vulnerable to becoming a patsy in someone else’s scam.  The musician doesn’t understand the issue himself but is content to parrot what he has read, and does not hesitate to tell anyone who disagrees that they’re wrong, even if they might be more knowledgeable than he is.

I agree that it is at least somewhat logical for a layman to subscribe to the majority opinion.  I understand this reasoning.  But what is not logical is to fiercely argue a point of view on an issue that one really doesn’t understand.  This is not scientific; this is dangerous and ignorant.  One good and recent example of the dangers of widely accepted misinformation in the arena of health is the recent debunking of the myth that saturated fat causes heart disease.  The recent well-publicized cover of Time about the merits of dietary fat is a testament to this struggle.  Mainstream science and medicine has only recently come around on this myth, just ahead of Time magazine.  Until very recently, the idea that saturated fat causes heart disease was completely embraced by the medical community for 60 years – but why?

One guy, Ancel Keys, came up with a theory which he first presented in the 1950s that sought to establish a causal link between saturated fat and heart disease.  He cherry–picked data to support his theory and pushed it hard, hard enough that it came to be regarded as scientific fact, despite the significant flaws in his data.  The musicians from facebook would have been satisfied – “scientific consensus” had been reached, but that didn’t make Keys’ theory true.  However, that didn’t stop his theory from being quickly embraced with very little scrutiny, and the medically accepted recommendation for heart health given to nearly everyone for decades became to replace healthy saturated fats with vegetable oils and margarine. 

It has only been in the last few years that this has begun to change, even though the “AltMed quasi-cults” had been trying to warn us.  It turns out that saturated fat is much healthier for most people than the vegetable oils that margarine is made from.  In fact, heart disease has skyrocketed since the switch to margarine and vegetable oils, and we now understand that widespread consumption of low quality vegetable oils is largely responsible for the modern epidemic of heart disease we currently face. 

We must live with the fact that we let one man so drastically influence medical consensus without properly reviewing his flimsy data.  We must also live with the fact that it took 60 years and the prodding of the AltMed quasi-cults to get the medical community to wake up and notice, to put it bluntly, that anybody had done any research since Keys.  In the case of saturated fat, scientific consensus let ignorance reign and people died because of it.  We would be wise to learn from this mistake and do our best not to repeat it.

I personally don’t have much reverence for scientific consensus.  Some people get really turned on by it, but I don’t understand the appeal.  If everybody agrees about something it means we’re on the cusp of a new understanding of that subject, not that we’ve finally got it figured out!  When has that ever happened?  Never!  No, instead it means it’s time to question everything and to be ready to make that next quantum leap to the next level of understanding, even if doing so illuminates how wrong we’ve been about some things.  I firmly believe that almost every scientific consensus that has ever existed will eventually be proven wrong, and that revering them serves only to slow progress. 

Getting back to Keys and his hijacking of the scientific consensus, it’s absolutely amazing and terrifying that one person was able to singlehandedly derail medicine’s understanding of heart disease and saturated fat for 60 years.  It gives me goose bumps, and I think it’s worth reflecting on the weight of this for a few moments.  It’s not difficult to see the dangers of blindly following the consensus on anything, especially an area as important, complex, and as quickly evolving as health and medicine. 

Neither is it hard to see the parallels between the saturated fat debate and the current debate about GMOs.  At their core, both are about the food industry which is, in turn, about money.  The margarine industry years ago needed a scientific consensus to declare margarine “the heart-healthy alternative to saturated fat” in order to convince consumers to buy its margarine, and capitalized on Keys’ flawed research to market their products.  And Keys, of course, was happy to receive free publicity for his theory.

Fast-forward back to current day and the story is much the same, but with different players:  Companies like Monsanto want to patent and sell their GMO products and make money.  Making money is what businesses do, after all, and I don’t think it’s a bad thing.  But we need to make sure that we’re not repeating the mistake of blindly following what we’re told is scientific consensus, as we did with saturated fat.  We need to make sure that private interests are not rushing the availability and sale of dangerous products that have not been adequately tested for safety.

Maybe GMOs are safe.  That’s really not what this about.  I have gone out of my way to make this not be about that.  

This is about the perils of blindly following popular opinion, the so-called scientific consensus, a practice and mindset that are decidedly unscientific.  It’s about being aware that for many of the people involved, this is just a business decision, and that “scientific consensus” is a commodity to be purchased.  It’s about being aware that real science questions everything all the time, and that constant, meticulous and unrelenting self-scrutiny is what makes science such an incredibly powerful tool that is worthy of our respect.  But judging the merits of a scientific theory based on its popularity is just that – a popularity contest, and something that bears little resemblance to science as I understand it.

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