6.JUN.2019 7 MIN READ | 7 MIN READ

Dr Gwee Kok Ann, gastroenterologist at Gleneagles Hospital, dispels 5 common myths about gluten sensitivity.

You may have seen articles about anti-gluten diets such as ‘Whole-30’ circulating around the Internet, claiming to make you feel significantly healthier. Books such as Wheat Belly by Dr William Davis also entice people with their “lose weight fast” taglines. They make bold claims, but how true are they?

For someone who suffers from irritable bowel syndrome (IBS) or is sensitive to gluten (a protein found in wheat, rye, and barley), embarking on irregular diets can cause many problems. Some symptoms of IBS include abdominal cramps, irregular bowel habits, and change in the form of your stool which could range from loose and watery to hard and dry. About 12% of Singaporeans have IBS. Of these, only a small percentage are expected to have celiac disease, the most severe form of gluten intolerance.

Just like the sheer number of pseudo-diets out there, misconceptions about celiac disease, gluten intolerance, and wheat allergies are aplenty. Here are the 5 most common myths about gluten intolerance – debunked.

Myth #1: Celiac disease, gluten sensitivity, and wheat allergy are the same things

Although all 3 conditions involve an intolerance of wheat proteins, they are different conditions.

Celiac disease is an autoimmune disorder where ingestion of gluten causes damage to the intestinal lining, generating an immune response that could cause inflammatory reactions in many parts of the body. It is usually genetically inherited and has over 200 symptoms ranging from anaemia, stunted growth and infertility, to even developing other disorders such as multiple sclerosis and epilepsy.

Celiac disease
Gluten sensitivity
is a digestive disorder where a person reacts aversely to gluten, usually with symptoms of the gastrointestinal tract such as diarrhoea, bloating or gas. Most people who have this experience mild symptoms and disturbances. However, in some, this reaction can lead to impaired absorption of important nutrients such as vitamin B12, which in turn may explain the fatigue that these patients report. This condition is currently labelled as non-celiac gluten sensitivity (NCGS). NCGS can be more difficult to diagnose than celiac disease as the changes in blood tests and intestinal biopsies are more subtle and difficult to detect. Thus, it often requires more detailed and careful testing with highly sensitive tests.

It is important to make a firm diagnosis of NCGS as many patients who appear to have symptoms to gluten, may actually have wheat intolerance or other forms of food intolerance. It is important to understand that the term wheat, or other food, intolerance simply means that a person develops certain symptoms which they suspect to be triggered by that food.

In the large majority of food intolerance it is to the poorly digested, and easily fermentable, constituents of these foods. In general, with these foods, the majority of people (regardless of whether they complain or not) will develop symptoms of bloating and gas if a large quantity is consumed. This type of food intolerance can usually be predicted, and diagnosed by experienced physicians, without the need for any testing.

On the other hand, it is important to make a proper diagnosis of wheat allergy, which is an immune reaction to proteins found in wheat, and can be life-threatening. Simply put, it is a food allergy. People with wheat allergies should avoid consuming all wheat products. Symptoms of a wheat allergy include difficulty breathing, rashes, or swelling.

Do you suspect you have one of these conditions? Visit a doctor to get a proper diagnosis and diet recommendations.

Myth #2: Cutting out gluten-based foods is a healthier option, even if I don’t have gluten sensitivity

If you haven’t shown any symptoms, have no family history, and more importantly, no official diagnosis of gluten sensitivity, it would be a shame to deprive yourself of your favourite sandwich or pasta! Remember, wheat and barley provide their own nutritional values such as protein and fibre, and only pose a danger to people whose bodies have an aversion to them. Many times when a person feels discomfort after eating certain foods, it is intolerance, not an allergy. Food intolerance is generally harmless, and can be managed by just reducing the total amount eaten at one time, and taking them in small quantities.

Myth #3: I should start my child on a gluten-free diet from a young age

Gluten sensitivity and children
A common question from parents is: “Since children can develop symptoms of gluten sensitivity, should I start my child on a gluten-free diet from a young age?”

When you restrict your child’s diet, they may lack crucial nutrients such as vitamin B, antioxidants, and iron. On top of that, you’d also be depriving them of calories, which are essential for your child’s growth and development. As such, do not self-diagnose as you might cause them to suffer from nutrient deficiency and make it challenging for them to find food that they can eat when they grow up, amongst other health issues.

However, for children who may be genetically predisposed, or could be exhibiting signs of reacting to gluten, going on gluten-free diet may be necessary. It is important to consult a paediatrician who has expertise and interest in gluten sensitivity. In children who are truly reacting aversely to gluten, this could contribute to impaired growth. Unfortunately, there is still a thinking that this is a condition of European people, although there is very little evidence to say that it does not affect Asian children.

Myth #4: I have to swear off all wheat products if I’m sensitive to gluten

All grains (except rice) contain protein that is theoretically gluten, but people with celiac disease and most gluten allergies only react to gluten found in wheat, barley, and rye. Foods such as oats contain low levels of gluten, if any at all. However, oats have high levels of sugar known as fructans, which causes bloating, gas, and sometimes diarrhoea.

Most people with celiac disease can tolerate gluten-free oats. However, problems might occur if oats are produced in the same place as wheat, barley, and rye, as the oats can be contaminated by these grains. The safest grain for people with celiac disease is rice.

People who truly have NCGS or wheat intolerance could benefit from avoiding wheat for a while. Subsequently when they have lost their symptoms, it is possible to try reintroducing small quantities – ideally this should be done under supervision by a trained dietitian or doctor.

Myth #5: Gluten can cause IBS and gastric pain

Gluten cause IBS and gastric pain
Consuming gluten may result in IBS if you are gluten-sensitive. Since both IBS and gastric will cause pain in the upper abdomen, gluten-sensitive individuals may mistake IBS for gastric pain. Many people have it ingrained in their minds that a stomach ache is a definite symptom of gastric and sometimes self-medicate for it. This will cause problems if the issue is something more serious.

In addition, many patients are over-diagnosed with acid reflux and are prescribed proton-pump inhibitor (PPI) drugs such as omeprazole. These drugs may produce profound reduction of stomach acid, and prolonged acid suppression could paradoxically give rise to more IBS type symptoms as a result of small intestinal bacterial overgrowth.

So, should you get tested for gluten sensitivity?

If you have IBS, it’s good to keep a diary that tracks your daily consumption. Pay close attention to your gluten intake. However, you should also consider other foods that are high in fermentable sugars (known as FODMAPs) (eg. oats, fruits, many vegetables, dairy products) which are common causes of bloating and gas. If your diet is mostly made up of rice and fish or meats, it may not be worth testing. However, if you suspect that you are gluten intolerant, visit a doctor to be properly evaluated. It would be a shame to deprive yourself of foods based on unconfirmed suspicions.

Whether it be lifestyle trends circling the web, or hearsay from friends and family, it’s important to educate yourself on issues involving your health. Self-diagnosing is never a good idea, and it’s best to receive proper consultation from your doctor.


Article contributed by Dr Gwee Kok Ann, gastroenterologist at Gleneagles Hospital


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Gwee Kok Ann
Gleneagles Hospital

Dr Gwee Kok Ann is a gastroenterologist practising at Gleneagles Hospital, Singapore.