Coeliac disease and diabetes

Coeliac disease is a lifelong condition where your immune system reacts to gluten, a protein found in wheat, rye and barley.

This immune reaction damages the lining of your gut, making it hard to absorb nutrients from food properly. Coeliac disease is more common in people with type 1 diabetes because both are autoimmune conditions. Up to 10% of people with coeliac disease also have type 1 diabetes.

If you have type 2 diabetes you’re not at increased risk of coeliac disease as type 2 diabetes isn’t an autoimmune condition.

However, there are many people who have coeliac disease, but don’t know it. Here, we answer all your questions about the symptoms, treatment and management of coeliac disease and diabetes.

What are the symptoms?

They range from mild to severe and include:

• diarrhoea
• bloating
• nausea
• mouth ulcers
• tummy aches
• unexpected weight loss (but not in all cases)
• hair loss
• anaemia

Treatment of coeliac disease

Coeliac disease is not the same as having a food allergy or being sensitive to particular foods. The only treatment, once you have been diagnosed, is to cut gluten out of your diet completely for the rest of your life.

Coeliac disease and type 1 diabetes

As well as the symptoms mentioned above, recurrent hypos can also be a sign of coeliac disease in people with type 1 diabetes because their body is not able to use the carbohydrate for energy.

If you have coeliac disease and type 1 diabetes, you need to be referred to a dietitian by your GP or your gastroenterologist for individual advice on how to manage your diet.

Does a gluten-free diet affect diabetes?

If you have diabetes and are diagnosed with coeliac disease, your blood (sugar) glucose levels may change after you start the gluten-free diet. This can happen because taking gluten out of your diet allows the lining of your gut to heal so absorption of nutrients, including carbohydrate, will improve.

You may need to keep a closer eye on your blood glucose levels and it’s important to liaise with your diabetes healthcare team as your diabetes medication requirements may change.

Choosing gluten-free foods

New UK food labelling laws make it easier to choose gluten-free foods. By law, manufacturers must list the ingredients containing gluten in bold. These include wheat (including spelt, Kamut and seitan), triticale, barley and oats.

Common foods to avoid if you have coeliac disease include:

• wheat
• barley (including products that contain malted barley, such as malted drinks, beers, ales, lagers and stouts)
• bulgar wheat
• couscous
• durum wheat
• einkorn
• emmer (also known as faro)
• khorasan wheat (commercially known as Kamut)
• pearl barley
• rye
• seitan
• semolina
• spelt
• triticale

Eating oats with coeliac disease

Some people with coeliac disease are also sensitive to oats. This is because oats contain avenin, a protein that’s similar to gluten. However, most people with coeliac disease tolerate oats. However when you're first diagnosed with the condition, your doctor will advise you to avoid oats for the first six months to allow your symptoms to improve.

If your food becomes contaminated with gluten

Even tiny amounts of gluten may cause people with coeliac disease to have symptoms in the short term and gut damage in the longer term. For this reason, it’s important that people with coeliac disease make sure that any gluten-free food they are preparing or eating doesn’t become contaminated with gluten.

Although oats are safe to eat for most people with coeliac disease, it’s important that they aren’t produced in the same factory as wheat, barley and rye, as they can become contaminated with gluten by these grains. Only oats which are uncontaminated can be eaten by people with coeliac disease, who tolerate oats.

However, there are a small number of people with coeliac disease who may still be sensitive to gluten-free, uncontaminated oat products.

Following a gluten-free diet

There are three types of foods to look out for when planning a gluten-free diet:

• Naturally gluten-free foods
• Foods prepared with gluten-free substitutes
• Processed foods labelled as having no gluten included. 

Naturally gluten-free foods

These include vegetables, fruit, meat, fish, cheese, milk, eggs, potatoes, quinoa cassava, rice, and buckwheat and pulses (peas, beans and lentils).

Processed food

It’s really important to check that processed foods are gluten-free as it may not be obvious they contain gluten. For example, flours used in a product made from pulses, such as gram and urad flour, may be contaminated if they’re produced in the same factory as wheat, barley and rye even though they’re naturally gluten free.

Gluten-free substitutes

Most supermarkets and health food shops now stock gluten-free ranges, including gluten-free bread made from rice or potato starch flour. Gluten-free ranges are sometimes stocked on ‘free from’ aisles or stocked alongside foods containing gluten so be very clear what you are buying.

Don’t forget to look online, too. It can help you to save time and see the ranges available in store and by mail order.

Getting gluten-free food on prescription

Your GP can prescribe gluten-free foods. The list of foods available on an NHS prescription includes gluten-free bread, flour and pasta. Cakes and luxury-style biscuits are not included.

Try as many different brands and types as possible to find the ones that work best for you.

Cooking gluten-free foods

Cooking from scratch is a good way of making sure that a meal is completely gluten free. Enjoy Food has over 100 gluten-free recipes in its recipe finder for you to choose from.

When you’re cooking at home, it’s also important not to undo the benefit of following a gluten-free diet by letting what you’re preparing become contaminated with foods to avoid if you have coeliac disease.

Coeliac UK, a charity that gives help and advice to people living with coeliac disease, suggests these simple steps to help you keep the gluten-free food you’re preparing safe from contamination:

• wipe down all kitchen surfaces
• clean all pots and pans with washing-up liquid and water or use the dishwasher (very few washing-up liquids contain gluten, but if they do, standard rinsing will remove any traces)
• you don’t need to use separate cloths or sponges
• you may want to get separate bread boards to keep gluten-free and gluten-containing breads separate
• use a separate toaster or toaster bags
• use clean oil or a separate fryer for frying gluten-free foods
• use different knives and spoons to prevent breadcrumbs from getting into butter, jam and other condiments.

Where can I get help with a gluten-free diet?

Many manufacturers now produce packs for people newly diagnosed with coeliac disease to help them learn what gluten-free food ranges are available. Coeliac UK can also provide a list of manufacturers and their contact details.

For the most up-to-date product information Coeliac UK’s Food and Drink Directory or their smartphone app, Gluten Free on the Move, can help you manage a gluten-free diet.