Peanut allergies can cause breathing problems
A group of children with peanut allergies have had their condition effectively cured, doctors believe.
A team from Cambridge's Addenbrooke's Hospital exposed four children to peanuts over a six-month period, gradually building up their tolerance.
By the end the children were eating the equivalent of five peanuts a day.
It is the first time a food allergy has been desensitised in such a way, although a longer-term follow up is now needed to confirm the findings.
Peanut allergies affect one in 50 young people in the UK and commonly cause breathing problems.
But at their most serious, they can lead to a potentially life-threatening anaphylactic shock.
The Cambridge team started the children on tiny 5mg daily doses of peanut flour before they trained their bodies up to cope regularly with 800mg - the equivalent to five whole peanuts.
Kate Frost, the mother of a nine-year-old who was one of the four participants, said: "It's very hard to describe how much of a difference it's made - not just in Michael's life, but for all of us.
"A peanut allergy affects the whole family. You can't go out to a restaurant. If your child goes to a birthday party, he takes a packed lunch."
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The concept of desensitising people to allergies has been successfully done with bee and wasp stings and pollen allergies, but this is the first time it has been achieved with a food-related allergy.
A few trials were done in the 1990s using peanut injections, but these were not successful.
'Quality of life'
Dr Andy Clark, who led the research published in the journal Allergy, said: "Every time people with a peanut allergy want something, they're frightened that it might kill them.
"Our motivation was to find a treatment that would change that and give them the confidence to eat what they like. It's all about quality of life.
"It's not a permanent cure, but as long as they go on taking a daily dose they should maintain their tolerance."
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The team have now expanded the study to include another 18 children and say there is no reason why the technique would not work for adults.
John Collard, the clinical director of Allergy UK, said it was "an important step forward".
"This could make a real difference, but at this stage it is too early to tell whether it will work for everyone. We need to see it used on more people and over a long period of time."