This is the first time, to our knowledge, that a potential trigger for peanut allergy has been directly shown”
Prof Quentin SattentauUniversity of Oxford
Fatal reactions
Mice were exposed to peanut proteins through the skin or the stomach.
Animals given the dry roasted samples had a much stronger immune response - the body's way of fighting things that appear foreign to it - than mice given the raw versions.
In humans, immune responses vary. Some can be mild, causing rashes for example, but others can be extremely dangerous, leading to swelling of the mouth and breathing difficulties.
Scientists say it is likely to be the high temperatures used to roast nuts that are responsible for the chemical changes that, in turn, prompt the allergic reactions.
Prof Quentin Sattentau, who led the research, said: "This is the first time, to our knowledge, that a potential trigger for peanut allergy has been directly shown."
And researchers believe the findings may explain the lower allergy rates in East Asian populations where boiled, raw or fried nuts are a more common part of the diet than roasted ones.
But they warn that much more work is needed before doctors make any specific dietary recommendations.