Claims increasing daily ... Gluten is found in products that contain wheat, rye, and barley.

Claims increasing daily ... Gluten is found in products that contain wheat, rye, and barley. Photo: Michele Mossop

Gluten-free is a big buzzword with big bucks behind it. In 2010, the global market for gluten-free products was worth $2.5 billion. Over the next five years, it is expected to grow to more than $5 billion.

But, how much of the buzz behind being gluten-free is bona fide?

A new study raises questions about the hype surrounding the gluten-free phenomenon. According to the study published in the Annals of Internal Medicine, titled Nonceliac Gluten Sensitivity: Sense or Sensibility?, there are 4598 Google citations of noncoeliac gluten sensitivity for every science journal article about the condition.

Loaf, loaves of bread.

Tasty but toxic? ... gluten sensitivity is on the rise. Photo: Quentin Jones

"Considerable debate about noncoeliac gluten sensitivity has recently surfaced on the internet, with a sharp increase in forums, patients or patient groups, manufacturers, and physicians advocating a gluten-free diet," the study's authors said. "Claims seem to increase daily, with no adequate scientific support to back them up."

The researchers acknowledge that "recent studies support the existence of a new condition, noncoeliac gluten sensitivity", but say gluten may not be the problem in a lot of the sensitivity that patients feel.

Gluten is found in products that contain wheat, rye and barley. In the study, the researchers noted that other ingredients in wheat flour or wheat-based foods may actually be causing symptoms that might be attributed to gluten sensitivity.

Yet, another study was specifically designed to establish whether gluten or fructans, which are another component in wheat, was the culprit. In the study, subjects were given bread and muffins that were low in starch. One batch of the bread and muffins contained gluten, the other did not.

The study found that gluten itself may trigger gut symptoms and fatigue in individuals who do not have coeliac disease.

"There was a clear difference in symptoms [between those who had the muffins with gluten and those who didn't]," says co-author of the study and Director of Medicine at the Angliss Hospital in Melbourne, Dr Evan Newnham. "There's a perception that [gluten-free] is a fad and that gluten is an evil food. But trials [like these] establish that it might be a clinical and medical problem."

Indeed, an essay published in the BioMed Central Journal says that gluten is "toxic" to humans and predicts that gluten-related problems are set to rise.

Since the introduction of grains containing gluten to the human diet about 10,000 years ago, selective breeding has seen the gluten content of wheat rise considerably to make it more palatable. The offshoot of this is that it is more harmful to humans. "Wheat varieties grown for thousands of years and mostly used for human nutrition up to the middle ages ... contain less quantities of the highly toxic 33-mer gluten peptide."

The authors say that our gastrointestinal and immunological responses have not adapted and so we remain "largely vulnerable to the toxic effects of this protein complex ... All individuals, even those with a low degree risk, are therefore susceptible to some form of gluten reaction during their life span."

But, because it is only in the last decade that coeliac disease and gluten sensitivities (for which doctors cannot test) have moved into the spotlight the research is still in its infancy. Which makes the distinction between how much is fact or fad a challenging call to make.

And it is not just the medical professionals debating the issue.

Mia Freedman recently expressed her exasperation in a post titled: "Does anyone eat anything anymore?". In the blog, she quotes nutritionist, Joanna McMillan.

"Some people cannot tolerate gluten yet suddenly everyone thinks gluten is bad. The truth is: it is modern refined foods that are causing most of our health problems. Not the individual components of food. We're missing the point."

"It never used to be like this," Freedman says. "Nobody had an intolerance when I was a kid, let alone wanted one."

In response, blogger and author, Sarah Wilson wrote an article titled "What's with all the gluten intolerances?? let me explain..."

"The short form: gluten is a poison," she says. "We tolerate it, and tolerate it, like cigarettes in the lungs. And then. One day. It's too much. Things tip over and BANG we have lung cancer. Or gluten intolerance. Or coeliac's disease."

Wilson also points out that we eat more wheat than ever before and cites the Pottinger cats theory as a possible explanation for the growth of gluten-related problems.

Over a period of ten years, Pottinger conducted a series of diet experiements on cats. "He found the illnesses (including infertility and the same degenerative diseases we're now seeing in humans) took several generations to kick in. And that it took four generations again of being fed good food for normal health to be restored," Wilson said.

"The point being...intolerances haven't just suddenly happened now. They've built up and accumulated over the generations. Our grandparents started eating processed, high-wheat and gluten diets. Now we're copping it."

There is something to this, says Newnham. "Environment, awareness...genes and how [previous generations] have eaten all have a role," he says. "The difficulty is to tease it all out."

Teasing out is exactly what the medical profession is now attempting to do. "While [gluten sensitivities] are anecdotally common, the medical community has been slow on the uptake," Newnham says. "On the whole we do tolerate [gluten], but it's increasingly recognised that there is a subset of the population that doesn't. What we don't know is the prevalence...[it] still needs more research"

If you do believe gluten is causing you problems, Newnham does not see a problem with going gluten-free provided it is done under the supervision of a dietitian or doctor. "But, I'd just like to emphasise that before embarking on a gluten-free diet ensure you don't have coeliac disease. Complications can ensue [if you do] and you can find out with a simple blood test or endoscopy."

What's the difference:

Coeliac disease (CD) is an autoimmune enteropathy triggered by the ingestion of gluten. Gluten-sensitive individuals (GS) cannot tolerate gluten and may develop gastrointestinal symptoms similar to those in CD, but the overall clinical picture is generally less severe.

Gluten sensitivity refers to an adverse reaction to eating gluten that usually does not lead to damage of the small intestine.

Wheat allergy is not specifically related to the gut. Reactions to wheat can vary significantly and like other classic food allergies can affect the skin, gastrointenstinal tract or respiratory tract.

Coeliac denotes a response to gluten that causes the immune system to attack its own body tissue

For more information go to: http://gluten-intolerance-symptoms.com/ or www.gesa.org.au