06/23/2013 12:15 pm ET Updated Aug 23, 2013

Just My Opinion

My friend Dr. Walter Willett -- and we are indeed friends -- was recently raked over the coals for the very strong negative opinions he expressed about a meta-analysis suggesting that some degree of overweight might actually be good for health. Both Dr. Willett and Dr. Katherine Flegal, lead author of that now rather notorious meta-analysis, are quite capable of defending themselves, so I leave them to it. As for the meta-analysis and its implications, I have already weighed in on that topic both online and in a NPR conversation directly with Dr. Flegal.

My topic today is not any given study, but the aggregation of studies and how we react to both. My topic today is the proliferation of opinions about scientific evidence that go well beyond the scientific evidence. My topic today is, bluntly, my opinion about opinions.

In my opinion, science should not be treated like a ping pong ball. No one study replaces all that came before. Every study should be interpreted in context, situated into the prior body of accumulated understanding, because that's where studies make sense. We should interpret each new study with an open mind -- but not so open our brains fall out.

I hasten to express the opinion that people should not, as a matter of routine, hasten to express their opinions.

I adamantly share the opinion that often, people are far too adamant when sharing their opinions.

I opine with religious zeal that people opine far too often with far too much religious zeal on topics having nothing to do with religion.

I note with equal conviction that not all conviction is created equal. Expertise actually does matter -- in any field.

I strongly espouse the view that strongly-espoused views when they aren't doing mischief in their own right are all too readily diverted into the realm of unintended consequences.

And finally, I offer as food for thought the notion that entire industries feed on conflicting opinion, and like nothing better.

But I must attach an important proviso to all of this: It's just my opinion.


For the "Katz Opinion Chronicles," please see these links:

Dr. David L. Katz;

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