If you've been skipping the bakery in favour of the gluten-free shelves at the supermarket, you might want to think again.
Many people are following a gluten-free diet under the mistaken belief they are intolerant, and it could be harming their health and their wallet, Australian researchers have found.
A review by University of Newcastle researchers released on Monday examined all the latest findings on gluten intolerance, after a study released in Europe earlier this year found that just 16 percent of people who believed they had a gluten sensitivity actually reported negative effects when eating it, in a blind study.
Gluten-free diets may not provide adequate amounts of trace elements and vitamins such as calcium, vitamin D, folate, thiamine, riboflavin and niacin."
That means five out of six people studied seemingly had no negative effects from eating gluten.
The Australian researchers found that a lack of research on how gluten intolerance (or non-Coeliac gluten/wheat sensitivity -- NCG/WS) differs from other gastrointestinal diseases was adding to community confusion around gluten, and potentially harming the community's health.
The gluten-free market is a booming industry, currently valued at around $7.6 billion worldwide.
What IS Gluten, Anyway?
Gluten is, in fact, a protein -- or a composite of proteins, to be exact -- found in many grains, including wheat, barley, rye and oats.
It's what gives bread and other glutenous foods their soft, springy texture.
Many gluten-free breads, pastas and other products substitute other flours, such as rice flour, which are often lower in protein and important micronutrients.
"Gluten-free products are not necessarily equivalent to their gluten-containing counterparts regarding their macronutrient and micronutrient content," the researchers stated.
"Gluten-free diets may not provide adequate amounts of trace elements and vitamins such as calcium, vitamin D, folate, thiamine, riboflavin and niacin."
They identified several previous studies assessing people who followed gluten-free diets. It found they were more likely to be deficient in the key nutrients, including folate and vitamin B.
Not only this, but many food manufacturers add additional oils and salt to gluten-free foods in an attempt to replicate the flavour and texture of regular bread and pasta.
"A gluten-free diet may adversely affect cardiovascular risk factors such as total cholesterol levels, weight gain leading to obesity, glucose tolerance and blood pressure and may lead to development of the metabolic syndrome," the University of Newcastle researchers note.
"A potential explanation for this is the higher glycaemic load of gluten-free foods."
Glycaemic load is a measure of how much a particular food will raise a person's blood sugar. A food with a high glycaemic load has a high potential to raise blood sugar, which long-term can put you at risk of diabetes.
And not only will it potentially harm your health -- a gluten-free diet will also hurt your hip pocket.
Many gluten-free products such as bread, pasta and flour cost as much as five or six times their gluten-containing equivalents.
A study conducted last year by University of Wollongong researchers weighed up an average family's weekly shop in the Illawarra region south of Sydney, and found that it cost around 17 percent more to follow a gluten-free diet.
So Why Are People Going Gluten-Free?
More than 7 percent of Australians believe they are gluten intolerant -- seven times the number believed to suffer from Coeliac disease (a serious condition where the immune system attacks gluten, causing long-term damage to the bowel and other organs).
However, as most people are self-diagnosed and there are currently no tests to determine gluten sensitivity, the true number of people with gluten intolerance are likely to be exaggerated, according to the MJA paper.
But that doesn't mean those stomach cramps and bloated belly are the invention of an overactive imagination.
Instead, many people who believe they have a gluten intolerance may in fact be reacting to another of the proteins in wheat -- which could mean that they can't handle wheat, but can still eat other gluten-containing products made of barley, rye and oats.
Another option, according to the research paper, is that they may have irritable bowel syndrome -- a condition believed to affect around one in five Australians. It has many similar symptoms as a food intolerance, including cramping, bloating, nausea, constipation and diarrhoea.
Gluten intolerance - more accurately described as non-coeliac gluten/wheat sensitivity, suffers report experiencing bloating, cramps, diarrheoa, constipation, nausea and vomiting, and sometimes headaches and tiredness. There is currently no way of diagnosing it without doing a blind study. Many people mistakenly believe they have gluten intolerance, when they may in fact have another condition, such as IBS.
Irritable Bowel Syndrome (IBS) - a debilitating condition with symptoms similar to gluten intolerance. It's estimated around one in five Australians have IBS. Following a low-FODMAP diet has been shown to help relieve symptoms.
Coeliac disease - a serious disease where the immune system reacts to eating gluten. If left untreated, it can cause damage to the small intestine, malabsorption of nutrients, diarrhoea, fatigue, anaemia and osteoporosis. Around 1 percent of Australians have the life-long condition and going completely gluten-free is currently the only effective treatment.
Wheat allergy - it's estimated that around 0.4 percent of the U.S. population are allergic to wheat proteins, albumin, globulin, gliadin or gluten. People may experience hives, swelling, irritation in the mouth or, in the most severe cases, anaphylaxis. Can be diagnosed through a blood test or a skin scratch test.
"Wheat contains compounds other than gluten that may have adverse effects on the intestinal mucosa and contribute to gastrointestinal symptoms, and adoption of a gluten-free diet is likely to decrease the ingestion of these compounds," the researchers explain.
These compounds are known as FODMAPS, and decreasing them in the diet has been demonstrated to help ease the symptoms of irritable bowel syndrome (IBS).
By cutting out bread, pasta and wheat, a person will likely ingest fewer FODMAPs, and so relieve their symptoms.
So What Should I Do?
If you're going gluten-free simply because it's a lifestyle choice or you believe it's a healthier way to live, chances are you're better off eating gluten as part of a balanced diet, with plenty of fruits and vegetables.
The University of Newcastle researchers are calling for more research into ways to diagnose gluten sensitivity, but in the meantime, if you are experiencing bloating, stomach cramps, wind and diarrhoea on a regular basis, it's important to get medical help.
A doctor will be able to rule out Coeliac disease -- an important step as, if left undiagnosed, it can lead to malabsorption of nutrients, diarrhoea, fatigue, anaemia and even osteoporosis.
If you do have IBS, trialling a low-FODMAP diet under the supervision of a qualified dietitian will help relieve the symptoms for many sufferers.
This involves reducing or eliminating foods including onions, garlic, mushrooms, apples, pears, mangoes, bread, milk and yogurt for a number of weeks before gradually reintroducing them to determine which foods are triggering symptoms.
You can find more information on irritable bowel syndrome and the low-FODMAP diet here.