Associated conditions

Coeliac disease is an autoimmune disease that appears in people who have the genes that predispose them to develop it.

For this reason, coeliac disease is more common among people with other autoimmune diseases, such as Type 1 diabetes and autoimmune thyroid disease. 

Lactose intolerance isn't an autoimmune disease, but can be associated with coeliac disease.

Lactose is a sugar found in mammalian milk (human, cows, sheep and goats), but not in soya or rice milk.

Symptoms of lactose intolerance are similar to that of coeliac disease and include nausea, bloating, abdominal pain and diarrhoea.

Why is lactose intolerance associated with coeliac disease?
 
The enzyme (lactase) that the body makes to break down lactose is found in the lining of the gut.  When people are first diagnosed with coeliac disease the lining of the gut is damaged by eating gluten. This can mean that the body doesn't make enough lactase, or the enzyme that is made doesn't work properly. 

Once established on a gluten-free diet the gut is able to heal and lactose digestion returns to normal.

Lactose intolerance is therefore usually temporary. Following a gluten-free diet means that most people with coeliac disease do not develop lactose intolerance.

If you think you may have a problem with lactose, it's important to discuss this with your dietitian, because cutting out lactose containing foods from your diet will greatly reduce your calcium intake. 

Following a diet suitable for a lactose intolerance is not the same as following a totally lactose-free diet. Tolerance to lactose varies between people, so you will need to have specific advice and monitoring from a dietitian.  Your dietitian will also be able to ensure your diet contains enough calcium from other sources.

Coeliac UK leaflets on lactose intolerance and diabetes are available to download on the Members area of our website. To sign up as a Member of Coeliac UK join here. If you're not a Member you can subscribe to have access to our resources.