Marks & Spencer is to support Coeliac UK in helping to raise awareness of the chronic intestinal disease.

Its three-year sponsorship includes financial support and the use of M&S stores for Coeliac UK’s national leafleting day on Saturday 14 May.

The charity said the deal would help drive its Coeliac UK awareness campaign, ‘Is it coeliac disease?’. The aim is to find the estimated half a million people in the UK who are undiagnosed with the autoimmune disease caused by a reaction to gluten, a protein found in wheat, barley and rye. There is no cure and no medication, the only treatment being a strict gluten-free diet for life.

One in 100 people in the UK has coeliac disease, which causes damage to the lining of the intestine and prevents the body from absorbing important nutrients, with the prevalence rising to one in 10 for close family members. However, statistics show that only 24% of those with the condition have been diagnosed, leaving up to half a million people undiagnosed.

Coeliac UK’s online assessment, www.isitcoeliacdisease.org.uk, advises people whether they should be screened. More than 30,000 people have already taken the questionnaire, with around 10% of those recommended to seek advice being positively diagnosed.

“We are thrilled to have Marks & Spencer on board and their support will be invaluable in helping us reach out to the hundreds of thousands of people still to be diagnosed,” said Sarah Sleet, the charity’s chief executive.

Claire Hughes, head of nutrition for M&S, said it was important the public was made more aware of the symptoms of coeliac disease so more people could get a diagnosis and support.

“Our product teams work hard to ensure that we have a wide range of gluten-free foods with the same great taste and flavour you would expect from M&S.”

For a full diagnosis, a person has to have consumed gluten every day for six weeks.