In the latest Eat This Podcast, Victoria Young talks about living with, and indeed enjoying, the Specific Carbohydrate Diet™. For those of you who don't know it, this is a very restrictive diet that people claim can reduce the symptoms of ulcerative colitis and Crohn's disease and, with time, perhaps even cure the disease itself. Many doctors dismiss it out of hand. But just because a medical thing requires the use of initial caps and a TM symbol doesn't automatically make it crazy. And just because many (most?) doctors dismiss it out of hand doesn't make it sane.
People talk about mind and body as if they were separate things, but I've long been of the opinion that the mind (or at any rate the brain) is just another organ, and like all the other organs, it can affect other parts of the body. People also talk about psychosomatic illnesses as if they were somehow not "real" illnesses, but that's scant comfort to someone suffering from, say, a phobia. The thing is, the brain (or mind) being a rather powerful organ, it often has an undue influence on the rest of the body. Placebos and nocebos work, of that there is no doubt. In the case of the SCD™, though, it seems unlikely that the effects of "forbidden" foods are mediated purely through the brain. There must, I feel, be a more direct effect on the guts, possibly, as its proponents claim, through the gut flora.
On gluten, though, I am not nearly so sure. Of course there are people for whom the consumption of gluten, even unwittingly, will trigger a reaction. But I do not believe that to be true of the vast numbers who have declared themselves gluten intolerant. I'm not saying they shouldn't eat however they choose, identify however they wish, or any of that. In fact, I declare myself to be gluten-intolerant tolerant. But I am saying that the massive expansion of wheat bellies owes less to actual gluten intolerance than to other factors.
Michael Specter's article Against the Grain in The New Yorker is not a bad starting place if you want to read more.