Scientists hope to apply the success they have had with cashews to other tree nuts and peanuts. Getty

Allergy-free nuts are just a few years away, say US scientists.

The team of scientists revealed today that they are close to developing a cashew nut that can be eaten by nut allergy sufferers, after discovering how to modify the dangerous proteins which trigger deadly reactions.

Proteins in nuts can cause allergic responses ranging from mild itching in the mouth or skin, to life-threatening anaphylaxis, which swells the throat making it difficult to breathe.

The reactions occur when a sufferer's antibodies latch on to the proteins from the nuts.

Researchers in the US say they have worked out how to change the shape of the protein so the immune system doesn't notice them. This means allergy-free nuts could be on UK supermarket shelves in a couple of years.

The main issue with implicating this discovery, says agricultural research expert Dr Chris Mattison who is leading the research, is whether science is more effective in countering allergies by "changing the food" or by "treating the person".

"The only widely accepted practice for preventing an allergic reaction to nuts is strict avoidance: stay away from the food," Mattison said. "Clinical trials to test immunotherapy are underway, but we're approaching it from an agricultural perspective, rather than medical."

Mattison and his team plan to conduct experiments on other nuts to see if they can replicate the success seen with the cashew.

"One of our goals is to apply our knowledge from the cashew experiments to other tree nuts and to peanuts," he said.

The study was presented at the National Meeting of the American Chemical Society in San Francisco on Monday.