Thursday, July 9, 2015

The Myth of Big, Bad Gluten

update - added material about Grain Brain and  Wheat Belly at end

NY Times  As many as one in three Americans tries to avoid gluten, a protein found in wheat, barley and rye. Gluten-free menus, gluten-free labels and gluten-free guests at summer dinners have proliferated.

Some of the anti-glutenists argue that we haven’t eaten wheat for long enough to adapt to it as a species. Agriculture began just 12,000 years ago, not enough time for our bodies, which evolved over millions of years, primarily in Africa, to adjust. According to this theory, we’re intrinsically hunter-gatherers, not bread-eaters. If exposed to gluten, some of us will develop celiac disease or gluten intolerance, or we’ll simply feel lousy.

Most of these assertions, however, are contradicted by significant evidence, and distract us from our actual problem: an immune system that has become overly sensitive. [...]

Milk-producing animals were first domesticated about the same time as wheat in the Middle East. As the custom of dairying spread, so did lactase persistence. What surprises scientists today, though, is just how recently, and how completely, that trait has spread in some populations. Few Scandinavian hunter-gatherers living 5,400 years ago had lactase persistence genes, for example. Today, most Scandinavians do.

Here’s the lesson: Adaptation to a new food stuff can occur quickly — in a few millenniums in this case. So if it happened with milk, why not with wheat? [...]

Dr. Barreiro, who’s at the University of Montreal, has observed this pattern in many genes associated with autoimmune disorders. They’ve become more common in recent millenniums, not less. As population density increased with farming, and as settled living and animal domestication intensified exposure to pathogens, these genes, which amp up aspects of the immune response, helped people survive, he thinks.

In essence, humanity’s growing filth selected for genes that increase the risk of autoimmune disease, because those genes helped defend against deadly pathogens. Our own pestilence has shaped our genome.[...]

So the real mystery of celiac disease is what breaks that tolerance, and whatever that agent is, why has it become more common in recent decades?

An important clue comes from the fact that other disorders of immune dysfunction have also increased. We’re more sensitive to pollens (hay fever), our own microbes (inflammatory bowel disease) and our own tissues (multiple sclerosis).

Perhaps the sugary, greasy Western diet — increasingly recognized as pro-inflammatory — is partly responsible. Maybe shifts in our intestinal microbial communities, driven by antibiotics and hygiene, have contributed. Whatever the eventual answer, just-so stories about what we evolved eating, and what that means, blind us to this bigger, and really much more worrisome, problem: The modern immune system appears to have gone on the fritz.

Maybe we should stop asking what’s wrong with wheat, and begin asking what’s wrong with us.

Dr David Katz in The Atlantic
Dr. David Katz is the founding director of Yale University's Prevention Research Center. He is an epidemiologist who has published two editions of a nutrition textbook for healthcare professionals called Nutrition in Clinical Practice. The third edition, nearing publication, will have nearly 10,000 citations. He is also the author of the nutrition book Disease Proof: The remarkable truth about what makes us well. Like Perlmutter, he also cites this era as a gold-standard. Apart from that—and a first name and medical degree—the two have little else in common.
“I find the whole thing a little bit sad, to be honest with you,” Katz told me. “In several ways. Beginning with the fact that I actually like Dr. Perlmutter. He does some really interesting and innovative work in the area of neurodegenerative diseases. He’s cutting edge and is doing stuff that’s a little bit out there. But he generally does this carefully and has actually provided some useful guidance we’ve applied in my own clinic; and I have a longstanding relationship with him—or at least his clinic—and we’ve corresponded and I generally think very highly of him. So I find it sad to be in a position to say that I think so much of his book is a whole bunch of nonsense.”

Katz paused.

“Now, he’s absolutely right that we eat too much sugar and white bread. The rest of the story, though, is one just completely made up to support a hypothesis. And that’s not a good way to do science.”

This launches the discussion of what science is—the critical point that confronts every mainstream media health and science writer. Most recently and famously we have heard about it in criticism of the works of Malcolm Gladwell and Jonah Lehrer (outside of the latter’s self-plagiarism debacle). The law of good science is that you can’t say “I’ve got an idea and I’m going to fall in love with it and selectively cite evidence to support it.”

“You’re only being a good scientist,” Katz said, “if you say, ‘I’m going to try to read the literature in as unbiased a manner as I possibly can, see where it leads me, and then offer the advice that I have based on that view from an altitude.’ I don’t see that going on here, and again, I think it’s kind of sad because I think the public is being misled.”

“I also find it sad that because his book is filled with a whole bunch of nonsense, that’s why it’s a bestseller; that’s why we’re talking. Because that’s how you get on the bestseller list. You promise the moon and stars, you say everything you heard before was wrong, and you blame everything on one thing. You get a scapegoat; it’s classic. Atkins made a fortune with that formula. We’ve got Rob Lustig saying it’s all fructose; we’ve got T. Colin Campbell [author of The China Study, a formerly bestselling book] saying it’s all animal food; we now have Perlmutter saying it’s all grain. There’s either a scapegoat or a silver bullet in almost every bestselling diet book.”

The recurring formula is apparent: Tell readers it’s not their fault. Blame an agency; typically the pharmaceutical industry or U.S. government, but also possibly the medical establishment. Alluding to the conspiracy vaguely will suffice. Offer a simple solution. Cite science and mainstream research when applicable; demonize it when it is not.

“It makes me sad that somebody like you is going to reach out to me, so you can get what I’d like to think are sensible comments about a silly book. If you write a sensible book, which I did—it’s called Disease Proof , and it’s about what it really takes to be healthy, brain and body—nobody wants to talk about that. It has much less sex appeal. The whole thing is sad.”

Negative reviews of Grain Brain and Wheat Belly -

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