Consumer behavior in North America indicates a growing number of people think gluten is bad for their guts. Meanwhile, journalists are baking up stories and scientists are still digesting the biology.
As he watched a large proportion of friends and family forsake flour for spelt bread and rice crackers, Western University, MAJ student, Jacob Kuehn, grew suspicious of media coverage of the gluten-free dietary phenomenon. He decided to take a closer look at the science behind gluten sensitivity, and why the media may be missing it.
Recently, The Globe and Mail’s Wendy Leung declared the formerly fringe gluten-free diet had “gone mainstream,” citing a prediction that the U.S. market for gluten-free food products will surpass $5 billion within three years. That would represent a nearly six-fold increase since 2006.
Celebrities such as Gwyneth Paltrow, Zooey Deschanel and Billy Bob Thornton are leading the charge to the specialty food aisle.
Far from the trendy fad it is today, the gluten-free diet used to be the unenviable sustenance of the roughly 3 to 12 people out of every thousand who live with a genetic condition called celiac disease. When a person with celiac ingests gluten it triggers their immune system to attack the lining of their intestines, and as a result they must avoid it completely.
Ironically, the diet is considered so burdensome by the celiac community—about half of whom are estimated to occasionally consume gluten accidentally—that researchers are actively searching for other ways to treat the disease in order to make life easier for its sufferers.
But the surge in gluten-free eating coincides with a widely-publicized new condition which has been the object of a lot more speculation than scientific research: gluten sensitivity.
A lot of that speculation is made possible by the fact that non-celiac gluten sensitivity remains under-researched and amounts to little more than a grouping of symptoms including stomach pain, diarrhea, tiredness and, occasionally, skin irritation.
It’s pretty normal for healthy people to experience at least some of those discomforts in the course of life, making room for pseudo-science to flood the public domain with unreliable information. Driving the point home, the authors of an editorial published recently in the Annals of Internal Medicine found that Google-indexed webpages about the condition outnumbered scholarly citations in the medical database PubMed by a factor of 4598 to one.
Some of those websites, like glutenfreenetwork.com, say gluten intolerance probably affects 15 per cent of the population or more. Some of the most far-flung reports site much higher prevalence rates and attribute schizophrenia, autism, or epilepsy to the condition.
The issue at hand is not whether non-celiac gluten sensitivity actually exists. A February article by Adriana Barton published in The Globe and Mail rightly points readers towards a placebo-controlled, small but double-blinded study conducted last year in Australia.
The study examined 34 non-celiac patients who all suffered from symptoms associated with gluten sensitivity and was the first to test definitively whether those symptoms were indeed caused by eating gluten products. The results, published in the American Journal of Gastroenterology, show that gluten did indeed trigger higher levels of tiredness, bloating and diarrhea in those participants.
Mainstream media coverage is only recently starting to take a critical view of gluten-free bandwagoning, with articles published last month in The Globe and Mail and Toronto Star pointing out that the diet is not necessarily healthy.
However, there is still some work to be done in order to correct inflated estimates of the prevalence of gluten sensitivity included in earlier coverage. Up until a few months ago, journalists fairly routinely parted from the realm of science in favour of false on this topic, with the article by Barton serving as an illustrative example.
In her article, Barton cites a chiropractor/nutritionist who provides an outrageous estimate that 40 per cent of people may suffer from gluten intolerance based on observations at her “wellness centre” and information received from a clinic which provides mail-order stool analysis and other sensitivity detection services at a cost of $99-$539.
In a desire to capture the “alternative medicine” side of the story, Barton ignores her source’s obvious conflict of interest – as well as broader scientific consensus.
In the real science world, researchers do not know how gluten interacts with non-celiac sufferers’ digestive systems. That means only rough estimates based on patient-reported symptoms can be made about the proportion of people who suffer from a genuine biological condition. Those estimates are not as accurate as one would like because it is always possible that symptoms attributed to gluten are actually explainable by something else.
That being said, even the very highest clinical estimates - published December 2010 in the journal Clinical Reviews in Allergy and Immunology - place the prevalence of gluten sensitivity at six to seven times higher than that of celiac disease. That’s about 10 per cent of the population if you round up numbers generously and lump people with celiac into the gluten sensitive camp – still a far cry from the forty percent figure cited in Barton’s article.
A review of scientific research published last June in the Journal of Internal Medicine suggests that gluten sensitivity most probably covers a number of unique conditions which all still require further research to explain and diagnose properly.
But that is about where science is at: uncertain about what causes gluten sensitivity and how many people may have it. And so, to really get to the bottom of the gluten question, journalists, doctors and patients will all need wait for scientists to catch up.
That doesn’t make for as colorful a story as the one Barton and others have turned out, but in the field of health reporting facts and science must reign supreme. When journalists skew those facts, there should be an onus to correct them.
After all, nobody wants The Globe and Mail readers to turn to spelt bread, rice crackers and gluten-free beer based on bad information.