“Common sense in an uncommon degree is what the world calls wisdom.”
Samuel Taylor Coleridge
Until a decade ago about 99% of people worldwide rarely seemed to be giving gluten much thought. Now, the fear of gluten has become so pronounced that almost one-quarter of the Western population consume gluten-free foods - a 67% increase from 2013. Gluten-free labels, gluten-free menus, and gluten-free parties. We even have gluten-free dog food! The gluten-free industry has experienced growth of 136% from 2013-2015, with sales of $11.6 billion in 2015.
So what is gluten and what is the gluten-free craze all about?
Gluten is simply a protein, the main structural protein of wheat, barley, rye, and triticale which is a cross between wheat and rye. We can find it everywhere - in bread, pasta, soup, sauces, food colouring, even in beer, so eliminating gluten is challenging. While most people may choose gluten-free foods simply believing that they can feel healthier, gluten poses a real danger for people with celiac disease, wheat allergy or gluten intolerance.
Celiac disease is a serious illness caused by the body’s immune reaction to gluten. When gluten enters the small intestine, the body recognises it as an invader and activates the immune system in an attempt to fix the problem. Over time, the lining of the small intestine gets chronically inflamed, and people are no longer able to absorb all of the vital nutrients they need.
Celiac disease causes weight loss, bloating and diarrhoea. It’s not easy to diagnose the celiac disease as most people don’t have any serious symptoms, or they ignore the existing ones. At the time of diagnosis about 20% people with celiac disease have constipation, 10% are obese, and 75% of children with celiac disease are overweight. The symptoms are not specific.
Those whose family members have celiac disease are often at a higher risk. Celiac disease is also more common in people with type 1 diabetes, autoimmune thyroid disease, microscopic colitis, Down syndrome and Turner syndrome. A simple blood test helps diagnose celiac disease, but the gold standard is endoscopy - a tube with a camera is placed in the intestine to look at the lining and take a biopsy.
There is no cure for celiac disease, and the only real treatment is a gluten-free diet for life. Although the diet works well for most people, it may take up to two years to heal the damaged intestine. Starting eating gluten again causes remissions.
A recent study estimated that about 1 in 100 people in the UK, and 1 in 140 people in the US live with celiac disease. Unfortunately, most cases are underdiagnosed which is probably why gluten gained so much attention. This is a real problem as most people don’t know they live with this serious disease.
The Journal of General Internal Medicine surveyed more than 2,400 patients with celiac disease. Only 11% were diagnosed by their GPs. They also surveyed the GPs, and only 35% of them had ever diagnosed celiac disease. Research has also shown that doctors would often misdiagnose celiac disease. People with irritable bowel syndrome, and iron deficiency, for example, are more likely to have celiac disease.
Many people with a variety of symptoms start self-diagnosing. They put themselves on a new diet saying that it makes them feel better. Then they declare that gluten-free diet is fantastic, and everyone should try it. That’s not how medicine works. If someone feels they may have celiac disease, they need to see a doctor as only a doctor can make the diagnosis. If celiac disease is diagnosed, the gluten-free diet is necessary; it's a form of treatment.
However, most people who start gluten-free diet don’t have celiac disease. Some may have a wheat allergy which is also very rare. In Europe for example, the prevalence of real wheat allergy is about 0.1%, in the US it’s between 0.4 and 1.0% which makes it even rarer than allergies to milk, eggs, soy, peanuts, fish and shellfish. Most of the wheat allergy occur in childhood, and many children outgrow it, so wheat allergy is even less common than celiac disease especially in adults. If someone is diagnosed by a doctor with a wheat allergy or gluten intolerance, then gluten-free diet is recommended.
Let's go to the research.
A couple of years ago a study published in the American Journal of Gastroenterology supported the idea of gluten intolerance. Researchers enrolled 34 patients who claimed gluten intolerance and asked the participants to eat either gluten or gluten-free foods in the form of two slices of bread. They found a significant difference in symptoms, pain, bloating, tiredness and satisfaction with stool consistency. Their conclusion was: "non-celiac gluten intolerance may exist, but no clues to the mechanism were elucidated.”
This research opened a big debate and thousands of people started a gluten-free diet to “cure” all of the symptoms mentioned in the research. Gluten became public enemy based on one research with 34 people involved. Since then many other, better designed and more sophisticated clinical trials were conducted to see the impact gluten may make on our health. The most reliable clinical trial concluded: “In a placebo-controlled, cross-over re-challenged study we found no evidence of specific or dose-dependent effects of gluten in patients with non-celiac gluten sensitivity placed diets low in FODMAPs.” In other words, the gluten-free diet made no difference.
A newly published study looked at people who claimed they had gluten sensitivity. Researchers studied 147 patients, 72% of whom didn’t meet criteria for gluten-sensitivity, despite having made self-diagnosis or even having been diagnosed with gluten-sensitivity, most often by non-physicians. In 25% of these people, their symptoms were poorly controlled even with the gluten-free diet. Gluten sensitivity probably does exist, but it is a highly rare condition, and it certainly doesn’t explain why millions of people around the world are giving up gluten.
For those who are not diagnosed with gluten-related conditions, like celiac disease or wheat allergy, substituting gluten free products for similar gluten-containing products doesn’t make any difference. In fact, it may make things worse. A recently published article has shown that gluten-free products are often higher in carbs and sodium and lower in fibre and protein than some gluten-containing products. Gluten-free cereals, for example, can have significantly fewer vitamins and minerals than gluten containing cereals.
It is important to remember that the number of many immune diseases have increased over the last few decades. We have become more sensitive to pollens so we suffer from hay fever. We don’t tolerate our own microbes so we have developed inflammatory bowel disease or we fight against our own tissues like in the cases of multiple sclerosis. The Western diet loaded with processed foods is recognised by the body as pro-inflammatory. Our intestinal microbial communities have shifted, and our modern immune system has become weaker.
Gluten has done much good to our health for more than ten millennia. It’s bad for some people indeed, but the epidemic of gluten intolerance has gone way over the top. Instead of eliminating gluten we need to eliminate a collective anxiety that causes imagined intolerances and allergies in otherwise healthy people.
The gluten-free diet is not for everyone. It is as important for people with celiac disease as insulin is for people with diabetes. Understanding what gluten is and how our body works is fundamental to making informed, personalised, evidence-based decisions when it comes to our health and lifestyle choices.