For many parents, the only help available has been from the Anaphylaxis Campaign, which has spent six years working to raise awareness of potentially lethal food allergies. It now has 5,600 members – most of them parents of children with serious allergies.

Chairman David Reading helped to launch the campaign in 1994, following the loss of his 17-year-old daughter Sarah who died after eating a lemon meringue pie in a restaurant.

He said: "She knew she was allergic to peanuts, but we didn't know it could be fatal. A lot has changed since then, but people are still dying unnecessarily."

Despite extensive research, specialists are still unsure about the causes of such severe allergic reactions. Dr Ewan believes nut allergy stems from the general increase in allergic disease, coupled with a change in infant diets, with peanut butter becoming more popular in recent years.

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