Coeliac disease is also called gluten intolerance or gluten sensitivity. It's an auto-immune disease, which means the body's immune system attacks itself. The type of reaction it causes is different to a food allergy - it doesn't cause anaphylaxis. Many people with coeliac disease don't realise they have it.
When people with coeliac disease eat foods containing gluten, it damages the lining of the small intestine, which stops the body from absorbing nutrients. This can lead to diarrhoea, weight loss and eventually malnutrition.
Foods to avoid
Gluten is a protein found in wheat and also in a number of other cereals including rye and barley. So, if you have coeliac disease you need to avoid foods made from these cereals, including most types of bread, pasta, pizza, pastry, biscuits and cakes.
Wheat ingredients are used in many foods, such as some sausages and burgers, and many sauces. Foods in batter or breadcrumbs aren't suitable for people with coeliac disease either. If you have coeliac disease, always check the ingredients on the foods you buy. You also need to avoid some alcoholic drinks made from barley, such as beer and lager.
Since November 2005, food labelling rules require pre-packed food sold in the UK, and the rest of the European Union, to show clearly on the label if it contains cereals containing gluten, including wheat, rye, barley and oats (or if one of its ingredients contains these).
There are lots of foods that naturally don't contain gluten. Rice, potatoes and corn are all gluten free and are good sources of starchy carbohydrate. Fruit, vegetables and unprocessed meat and fish don't contain gluten either. People with coeliac disease can also buy special products designed for them.
From January 2009 the rules about the labelling of foods specially prepared for people with gluten intolerance are changing. The phrases 'gluten free' and 'very low gluten' will only be able to be used on certain foods and will have a specific meaning. 'Gluten free' will be allowed on foods that contain less than 20 parts per million gluten and most people with coeliac disease will be able to eat all of these foods. A second category of products labelled as 'very low gluten' will include only those products which are manufactured using a special type of starch that has been treated to take out almost all of the gluten and will generally have a higher level of gluten in them (up to 100 parts per million). Not everyone will be able to eat these foods, so it's important to speak to a doctor or dietician before introducing them into your diet for the first time.
Some people with coelaic disease find they cannot eat oats. Oats contain a protein that is similar to gluten, but not exactly the same. It's also possible for small amounts of other cereals, such as wheat, to get into oat products when the crop is growing, or being harvested or transported. However, research has shown that some people with coeliac disease can't tolerate oats or oat products. At the moment, medical experts don't have enough evidence to decide whether all people with coeliac disease should avoid oats. The new rules allow products containing oats to be labelled 'gluten free' only if the level of gluten in the oats is less than 20ppm.
If you have coeliac disease you will probably be advised to avoid oats, as well as wheat, rye and barley, especially when you are first diagnosed. You should discuss whether to start eating oats again with your health professional because oats may not be suitable for some people with coeliac disease.
It's important to understand that products labelled 'wheat free' aren't the same as those labelled 'gluten free' or 'very low gluten'.
Wheat-free products may contain other cereals, such as rye or barley, so these won't be suitable for someone with coeliac disease, unless they are labelled 'gluten free' or 'very low gluten'.
'Gluten free' products and 'very low gluten' products may still contain other proteins found in wheat (albumins, globulins and starch granule proteins). So these might not be suitable for people who are intolerant or allergic to wheat.
Coeliac UK, a charity to support people with gluten intolerance, works with manufacturers to produce a regularly updated list of foods that don't contain gluten.
Causes of coeliac disease
We don't fully understand why some people have this condition, but it does often seem to run in families. Coeliac disease is often diagnosed after weaning, when cereals are introduced into the diet, but it can also be diagnosed at a later age, with many people not being diagnosed until later in life.
Some research suggests that waiting until a baby is about six months old before starting to give them foods containing wheat, such as bread, wheat flour, breakfast cereals and rusks, makes it less likely that they will develop coeliac disease. (Current advice is not to give your baby any solid foods until six months, unless your GP or health visitor advises you to.)
People with certain medical conditions might be more likely to develop coeliac disease, for example those who have Type 1 diabetes, thyroid problems, ulcerative colitis and certain neurological disorders, such as epilepsy.
There are blood tests that can help find out if someone has coeliac disease, but the only way to be certain is to do a biopsy, where a little piece of the small intestine is removed and examined under a microscope.
Until recently, coeliac disease was thought to affect about one in 1,500 people in the UK. However, evidence published in February 2004 suggests that about 1 in 100 have the condition. This figure is based on blood tests in children and hasn't been confirmed by biopsies. So coeliac disease might not be as common as the research suggests. However, many people with coeliac disease don't realise they have the condition and itís estimated that only 1 in 8 people have been diagnosed.
There is no cure for coeliac disease. The only way to avoid the symptoms is not to eat foods and drinks containing gluten. If people with coeliac disease don't control their condition, it can lead to anaemia, bone disease and, on rare occasions, certain forms of cancer. It can also cause growth problems in children.