In an experiment, allergy sufferers were given increasing amounts of peanut flour to eat until they had an allergic reaction, which was treated quickly.
This was repeated when they were exercising and when they were deprived of sleep.
The findings of the study, funded by the Food Standards Agency (FSA) and carried out at Addenbrooke's Hospital, Cambridge, have been described as "hugely significant" given that one in every 50 children has a potentially-fatal peanut allergy, The Daily Mail reported.
The FSA has been trying to improve allergen labelling following the death of Natasha Ednan-Laperouse, 15, after she ate a Pret a Manger baguette.
Just last week, there were demands for better information from the family of Owen Carey, who died after celebrating his 18th birthday at burger chain Byron where he was served chicken marinated in buttermilk – despite telling staff he had a dairy allergy.
The FSA said allergies remain an under-researched subject and the findings of the study will pave the way for a greater understanding of the factors that can lead to reactions and better labelling.
Lead investigator at Addenbrooke's, Dr Shelley Dua, said: "Precautionary allergen labels on food such as the commonly used 'May contain traces of..." are currently quite vague and not very helpful.
"This is partly because until now we simply haven't known enough about the amount of allergen which causes a reaction and how day to day factors like tiredness and exercise affect allergic reactions."