Symptoms of coeliac disease can range from mild to severe. They often come and go.
If your condition is mild, you might not notice any symptoms. The condition is often only found when you're having tests for another condition.
Treatment is recommended even when there are no symptoms, or mild symptoms. This is because complications can still occur.
Common symptoms
Diarrhoea is the most common symptom of coeliac disease. It happens when the body isn't able to fully absorb nutrients. The medical name for this is malabsorption.
Malabsorption can also lead to poo containing abnormally high levels of fat. This can make them foul smelling, greasy and frothy. They may also be difficult to flush down the toilet.
Other common stomach-related symptoms include:
- abdominal pain
- bloating and farting
- indigestion
- constipation
- vomiting (usually only affects children)
More general symptoms may include:
- unexpected weight loss
- an itchy rash
- difficulty getting pregnant
- tingling and numbness in your hands and feet
- disorders that affect coordination, balance and speech (ataxia)
- swelling of the hands, feet, arms and legs caused by a build-up of fluid (oedema)
- extreme tiredness
Extreme tiredness may be a sign of iron deficiency anaemia. It could also be a sign of vitamin B12 folate deficiency anaemia.
Malnutrition
If coeliac disease isn't treated, your food may not get digested in the normal way. This can cause you to become malnourished. This can lead to tiredness and a lack of energy.
Malnutrition in children can mean they don't grow at the expected height and weight. It can also cause delayed puberty.
Skin rash (dermatitis herpetiformis)
You may develop a skin rash. This happens when your body has an autoimmune response to gluten. The medical name for the rash is dermatitis herpetiformis.
The rash is itchy and has blisters that burst when scratched. It usually occurs on your elbows, knees and bum. But it can appear anywhere on your body.
Around 1 in 5 people with coeliac disease also develop this rash.
The exact cause of it isn't known. But it's also associated with gluten. Like coeliac disease, it should clear up after switching to a gluten-free diet.
Complications of coeliac disease
If you have coeliac disease, it's very important that you don't eat any gluten. Eating gluten can cause several complications.
It's a common mistake to think that eating a little gluten won't harm you. Eating even tiny amounts can trigger symptoms of coeliac disease. This can increase your risk of developing complications.
Complications include:
- malabsorption
- malnutrition
- lactose intolerance
- pregnancy-related complications
Malabsorption
Malabsorption is where your body doesn't fully absorb nutrients. This can lead to a lack of certain vitamins and minerals in your body.
It can cause conditions such as:
- iron deficiency anaemia
- vitamin B12 and folate deficiency anaemia
- osteoporosis – a condition where your bones become weak
Malnutrition
Coeliac disease causes your digestive system to work less well. Severe cases can sometimes lead to malnutrition. This is a critical lack of nutrients in your body. It can mean your body can't function normally or recover from wounds and infections.
If you have severe malnutrition, you may become fatigued, dizzy and confused. Your muscles may begin to waste away. You may find it difficult to keep warm. In children, malnutrition can cause stunted growth and delayed development.
Treatment usually involves increasing the calories in your diet and taking supplements.
Lactose intolerance
If you have coeliac disease, you're more likely to also develop lactose intolerance. This is where your body can't digest the milk sugar (lactose) in dairy products.
Lactose intolerance causes symptoms such as:
- bloating
- diarrhoea
- stomach pain
Unlike gluten in coeliac disease, lactose doesn't damage your body. But you may get some gut-related symptoms when you eat foods containing lactose. This is because you can't digest it properly.
You should not eat or drink dairy products that contain lactose. Dairy products are an important source of calcium. You'll need to compensate for not eating them by taking calcium supplements.
Cancer
Cancer is a very rare but serious complication of coeliac disease.
Someone with coeliac disease has a slightly increased risk of developing certain cancers. Recent research shows that this increased risk is less than was thought.
Cancers associated with coeliac disease are:
- small bowel cancer
- small bowel lymphoma
- Hodgkin lymphoma
Most people with coeliac disease won't develop any of these.
If you've been on a gluten-free diet for 3 to 5 years, your risk is the same as that of the general population.
Coeliac disease in pregnancy
Poorly controlled coeliac disease in pregnancy increases the risk of developing pregnancy-related complications. For example, giving birth to a baby with a low birth weight.
Read more about diagnosing coeliac disease
Content supplied by the NHS and adapted for Ireland by the HSE