As more and more of your friends go gluten-free, you may be wondering: Is there something to this craze? Is gluten intolerance a thing? Is it getting more common?
The answer is no.
Only about 1% of people worldwide actually have celiac disease, the rare genetic disorder that makes people intolerant to gluten. And that number is not on the rise, according to a recent study in the Journal of the American Medical Association.
Just this month, a group of experts tasked with deciding if we should screen healthy people for celiac concluded that the jury is still out on whether doing so would improve people's health.
And as for all those people who say they don't have celiac but are just "sensitive" to gluten, a 2013 study out of Monash University suggested that's probably not a thing, either.
Alan Levinovitz, an assistant professor at James Madison University, studies the intersection between religion and medicine, and says the recent uptick in self-diagnosed gluten sensitivities comes down to a mix of psychology and behavioral change.
In his book "The Gluten Lie," Levinovitz interviews Peter Gibson, a Monash University professor of gastroenterology who helped write the 2013 study that found non-celiac gluten "intolerance" was probably not real. Gibson says the reason many people who've cut gluten out of their diets claim they feel healthier is that they've changed how they eat.
"I've noticed [this] lots of times, even with family members," Gibson told Levinovitz. "They've decided they're eating a lot of takeaway foods, quick foods, not eating well at all. They read this thing about gluten-free, and then they're buying fresh vegetables, cooking well, and eating a lot better."
In other words, while cutting gluten may seem like it makes your stomach feel better or clears up your complexion, there could be many other causes.
"Blaming the gluten is easy, but you could point to about a hundred things they're doing better," Gibson said.
That reality can be a tough pill to swallow, however.
"When it comes to food sensitivities, people are incredibly unwilling to question self-diagnoses," Levinovitz wrote. "No one wants to think that the benefits they experienced from going gluten-free ... might be psychological."
On top of that, many people are not good at reliably connecting what they've eaten to physical symptoms. Studies have shown that we have trouble remembering what we ate and when we ate it, and that we're poor judges of what's healthy and what's not.
So rather than jumping to self-diagnose, see a doctor. And stick to the science.
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