A Press Association report this morning reported what many parents might have suspected for some time. It seems that that old answer to everything from behaviour to obesity - the food allergy is being wrongly diagnosed a lot of the time.

The Press Association report said that hospital admissions for food allergies among children rose by 500% in the past 20 years but many youngsters are being wrongly diagnosed with the condition due to unreliable testing kits available on the Internet, the UK NHS watchdog had said.

Between 6 and 8% of children under three in Europe and North America now have food allergies - a dramatic increase since 1990.

Reactions to food can be severe and are recognised as a major paediatric problem in the UK and other Western countries.

In a bid to help GPs spot the signs and symptoms, the National Institute for Health and Clinical Excellence (Nice) issued its first guidelines on food allergies in children.

The draft guidance also warns against allergy tests sold over the Internet and offered by alternative practitioners. These tests which include hair analysis and kinesiology can wrongly diagnose food allergies, leading to children being put on restrictive diets lacking in nutrients, it says.

The guidance tells GPs when to consider the possibility of a food allergy and when to carry out further testing.

For example, if a child suffers from skin conditions like eczema or itchy rashes, sneezing or shortness of breath, gastro-intestinal problems such as vomiting, difficulty swallowing or constipation, or anaphylaxis (a severe, hyper-sensitive reaction).

Methods of diagnosis include removing the suspect food from the diet for a period of time and then reintroducing it, skin prick tests and blood tests to detect antibodies.

Among the most common foods causing allergic reactions are cow's milk, fish, shellfish, eggs, peanuts, sesame, soy, wheat and kiwi fruit.

Dr Judith Richardson, associate director of Nice's Centre for Clinical Practice, said: "Many of the symptoms are common to other conditions, so it's not always easy to identify and diagnose food allergy correctly. This will be the first evidence-based guideline on how health professionals and others who work with young children should diagnose and assess food allergies in children