To diagnose and confirm the allergy exists, a child often needs to eat a peanut to set off the reaction to see how serious and life threatening it is.

Called a food challenge, it can cause the child to go into severe anaphylactic shock, have trouble breathing and start to break out in hives.

But staff specialist for paediatric allergy and immunology  Rani Bhatia and her research team at have found a way to make the experience much less stressful.

“It is a breathing test to measure the chemical in the breath which is nitric oxide,” she said.

“If there is a lot of the chemical it is bad and you can use it to predict how severe the allergic reaction will be.”

Dr Bhatia said it was hoped that this would reduce food challenges by 70per cent.

She said the breathing test combined with a blood test, would mean improved accuracy in the diagnosis. 

“There is also a blood test that can measure the specific biomarkers,” she said.

“The blood test has been around for a while now – the novel thing we are doing is measuring the breath.”

Dr Bhatia said  this new discovery and further research could one day lead to a cure.

“Food allergy is increasing – there’s been a fourfold increase,” she said.

“Our major problem is eggs but most children will outgrow it – only 30per cent of children with peanut allergies will outgrow it.”

Nicolas Maas, 14, is severely allergic to peanuts. Using the breathing machine yesterday he said it was a much nicer experience than going through a food challenge.

Nicolas  ate less than a teaspoon of peanut butter two years ago in  a  hospital test and he described the experience as “horrible”.

“I felt like I was going to die, my throat felt like it was closing up and I couldn’t breathe – it was the most terrifying thing I have ever experienced,” he said. 

“I’d never want to do that again – this is much nicer.”