Depending on who you talk to, going gluten free is either a vital step to preserving your health or just the latest diet fad. Gluten, a composite of proteins found in grains like wheat, barley and rye, is what gives bread a chewy quality. And food manufacturers add gluten it to entirely unrelated products like ice cream and soy sauce to give them body and stability. Only 10 years ago, gluten-free foods were a tiny niche category but now retailers from Whole Foods Markets Inc. (WFM) and even Wal-Mart Stores Inc. (WMT) are fully stocked. While there are some signs of a sector bubble, as there's a limit to just how gluten-free you can go, with global sales of gluten-free products expected to reach $6.2 billion by 2018, the trend isn't going away anytime soon. So what's driving this global aversion to gluten? There are three main reasons: celiac disease, gluten sensitivity and simple trendiness.

Celiac Disease

According to WebMD, celiac disease is a legitimate malady affecting an estimated 1% of Americans and Canadians, though generally less than 10% of existing sufferers are officially diagnosed with the disease. Those suffering celiac disease have to contend with a slew of digestive problems and have increased susceptibilities to other diseases like osteoporosis. They must go to extreme lengths to avoid anything containing more than 20 parts per million of gluten, or the equivalent of a 1/8th teaspoon of flour. So if you’ve nibbled on a piece of bread or sipped a beer without any drastic repercussions, you likely don't have celiac disease.

Non-Celiac Sensitivity

While non-celiac gluten sensitivity is now an accepted condition in the scientific community, knowledge of the condition remains limited. According to a study published by the University of Bologna, it's still unclear whether gluten itself causes the adverse effects or if culprits include other proteins and pathogenic mechanisms found within wheat products. The study raises the possibility that non-celiac gluten sensitivity could actually be an “umbrella covering different subtypes of illnesses rather than a single entity.” One of these potentially-harmful compounds is glyphosate, a commonly used pesticide known as Roundup. A study by MIT found a strong correlation between the rise in celiac disease and the use of a glyphosates.

The graph below shows a correlation between deaths due to intestinal infection and glyphosate on wheat (1000 lbs). (Source: "Glyphosate, pathways to modern diseases II: Celiac sprue and gluten intolerance," by Samsel & Seneff.)

Deaths due to intestinal infection and glpyhosate

Trend Following

Then there's the trend angle. Gluten-free diets are all the rage lately, with celebrities like Gwyneth Paltrow and Miley Cyrus touting the benefits of removing wheat from their diets. Some gluten-free advocates lump gluten together with lactose and genetically modified organisms as things to be avoided. They also tend to favor organic foods (for more, see: Is Organic Really Worth the Money?). Manufacturers couldn’t be happier. The gluten-free market has grown 26% year-over-year since 2008 and is now worth almost $500 million in Canada and $4 billion in the United States, annually. Note that despite there being only roughly 35,000 Canadians and 1.8 million Americans officially diagnosed with celiac disease, the number of people on gluten-free diets is much, much larger. Between four and seven million Canadians now avoid gluten and 29% of Americans are reducing their exposure or avoiding gluten altogether.

In short, gluten-free is now big business, and global food manufacturers such as General Mills and Betty Crocker are expanding their product line ups with a wide variety of gluten-free options. They're not only meeting customer demand: they're greatly increasing profits. On average, gluten-free products are 242% more expensive than their regular counterparts. In the graph below you can see reasons consumers give for eating gluten free.

Exhibit 2: "Reasons for Gluten-Free Consumption" (Source: adapted from Hartman Group 2013, Agriculture and Agri-Canada.)

Reasons for Gluten-Free Consumption

The Bottom Line

In the past decade, the gluten-free industry has gone from being an obscure niche to a multi-billion-dollar enterprise. Although the ranks of those diagnosed with celiac disease remains small, the number of gluten-free advocates is swelling, with some consumers adopting the dietary preference for its perceived health benefits. Though scientists have yet establish the veracity of non-celiac gluten sensitivities, let alone the alleged health benefits of avoiding gluten, for food manufacturers, the gluten-free boom has been among the greatest things since sliced bread.

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