Why and when can gluten be bad for you?

The simplest explanation of gluten is that it is a type of protein found in certain grains, especially wheat, barley and rye. When it comes to wheat, in particular, there are two primary types of protein that fall under the gluten category: gliadins and glutenins. These substances are known as seed storage proteins, which accumulate in the developing seed (the grain) as a reserve for nitrogen, carbon and sulphur, which will be used by the seedling when the next season comes and the seed germinates. These proteins are also what gives bread the ability to rise and lends it that elastic “doughy” texture we all know so well. The seed storage proteins in barley are called hordeins, and in rye secalins, but both are generally referred to as glutens. 

Why do people go gluten free? Is gluten bad for you? Some people have an intolerance of gluten. Eating gluten makes them unwell. Coeliac disease is an autoimmune disorder in which the body’s immune system attacks gluten in the gut, causing a range of potential symptoms and damage to the lining of the intestine that can lead to severe health complications. Coeliac disease affects around one person in 100. An even greater number of people have non-coeliac gluten sensitivity (NCGS), an intolerance to gluten that causes painful and debilitating symptoms but does not lead to the same kind of intestinal damage.  

Other people point to some evidence that gluten is related to various other illnesses and conditions, ranging from irritable bowel syndrome (IBS) and other digestive disorders to a series of autoimmune diseases and even autism in children. Some of these connections seem to be backed by science, while others remain controversial or, at least, yet to be proven.      

There is no clear medical advice at present for the general population to avoid gluten. However, as is explained later in this article, studies are ongoing about gluten’s possible role in contributing to several autoimmune diseases and other conditions that may have their origin in our digestive system and reactions to certain foods.  

What happens when you cut out gluten? It is not clear that cutting out gluten will make any difference to most people. For others who have certain conditions such as coeliac disease, going gluten free is a medical necessity. But there are theories that connect gluten with other conditions, not all connected to the digestive system, driving more people to attempt to avoid gluten in their diet.  

Coeliac disease 

Coeliac disease is triggered by the presence of gluten in the diet. Following a strict gluten free diet is the only treatment for coeliac disease, and, in the vast majority of cases, is extremely effective in eliminating symptoms and allowing the damage caused to the intestine before diagnosis to heal. The gluten free diet is also the only effective treatment for NCGS.  

IBS 

Studies have shown that around one third of people who suffer from IBS have seen improvements in their condition when switching to a gluten free diet. More research is needed, however, to determine which of those individuals are benefiting from avoiding gluten or from the effects of eating fewer carbohydrates and especially FODMAP short chain carbohydrates as a spin-off from changing diet and avoiding some grains and starches.  

Inflammation and leaky gut problems 

The intestinal lining is a tight barrier that controls what gets absorbed into our bloodstream. An unhealthy gut lining, such as is the case with a person with untreated coeliac disease, may have cracks or holes, allowing partially digested food, toxins and bugs to penetrate the tissues outside the lining and triggering inflammation and potential health problems within the gut and beyond. In some people, it appears that gluten causes the gut lining cells to release zonulin, a protein that can push apart the tight connections between the tissues, opening larger cracks.   

This increased intestinal permeability, sometimes known as ‘leaky gut’ is known to play a role in gastrointestinal conditions such as coeliac disease, Crohn’s disease and IBS. Some research also suggests that leaky gut may be associated with other autoimmune diseases (type 1 diabetes, lupus and multiple sclerosis), chronic fatigue syndrome, arthritis, fibromyalgia, allergies, asthma, acne, obesity and even mental illness. But more research is needed to establish a clear cause-effect mechanism. 

If you decide to go gluten free even though this is not a treatment you have been told to follow for a specific health reason, it can become harder to eat a fully balanced diet. Gluten itself is not essential for a healthy diet, but it is a part of many widely available foodstuffs. For example, fortified breads and cereals are a major source of B vitamins for many people, while gluten free flours tend not to be fortified. Vitamin B9, commonly known as folic acid, is important for everyone, especially women who are pregnant or about to conceive. Many doctors recommend that people on a gluten free diet also take multivitamin/multimineral supplements. 

For many people, whole wheat is a major source of dietary fibre, essential for properly functioning bowels. In developed countries, the average diet is lacking in fibre, so anyone avoiding many of the most common cereals will have to make a serious effort to make up for this by eating a large amount of other grains, beans, vegetables and fruit. A gluten free diet can be a healthy and balanced one, but it tends to require more work in terms of sourcing and preparing your food.