I’ve gotten a few emails in response to the NYT “gluten myth” piece asking how I could ignore pesticides in the celiac question. Interesting you should ask (and it’s something I want to look into)
While reporting, one scientist did in fact mention pesticide residues in food as a possible explanation for the rise of celiac. When I asked for evidence in support of the idea, however, he said that there wasn’t any — that it was pure speculation. Good scientist. Didn’t want to speculate.
In fact, though, there are a few suggestive animal studies. Here’s what I find interesting about the herbicide Roundup or glyphosate. In animal studies, it appears to do its damage by tweaking the microbiome — the community of microbes within — killing off “good” microbes, and allowing “bad” ones to bloom. That is, it seems to cultivate a “pro-inflammatory” microbiota, causing what’s sometimes called dysbiosis. (Here’s one study in a simulated cow gut showing an overgrowth of neurotoxin-producing bacteria. Yuck.)
There’s no GMO wheat currently being grown, and the stuff is mostly applied to crops modified to withstand it, meaning GMO corn and soy.
[CORRECTION NOV 29, 2015: I previously said that glyphosate can’t be entering the food supply on wheat because there’s no GMO wheat being grown. That’s true, but it turns out that the herbicide IS used to desiccate non-GMO crops before harvest. In other words, it IS applied to wheat.]
Anyway, the question is, what happens when you throw gluten into the gut that has an overgrowth of pathogenic bacteria? Does the abundance of nasty bugs provide that signal that I was going on about — the danger signal — that then causes the immune system to attack gluten? Pure speculation with no definitive proof, but here one group is making the argument.
Some years ago, I wrote about the microbiota in celiac. And here’s a fact: there are many ways to change the microbiota, to make it less than friendly. Diet is one, including too much greasy, sugary food. Certain emulsifiers in processed foods, as has been recently reported, are apparently another. They promote an overgrowth of nasty bugs. There’s also antibiotics.
All these factors have increased in recent decades in our lives. But none of them indicate much about the inherent toxicity of gluten.