Last reviewed 19 February 2021

Which is the allergen responsible for the most fatal reactions: cow’s milk or peanuts? And is there a gender split when it comes to fatal allergic reactions?

Seeking answers to these and similar questions, and recognising that the correct interpretation of data is crucial to giving an accurate picture, the Food Standards Agency (FSA) has been exploring the national data on anaphylaxis with a view to seeing how this can improve its work on food allergy.

It funded a study conducted by scientists from Imperial College London which has identified trends in food-induced anaphylaxis admissions and related fatalities from 1998 to 2018 in the UK.

Published in the British Medical Journal (BMJ) the report on the study’s findings can be found at https://www.bmj.com/content/372/bmj.n251.

One significant finding was that, despite headlines giving the impression that food-related anaphylaxis fatalities are on the rise in recent years, the study found the opposite to be true.

Deaths from food-induced anaphylaxis are in fact rare, it points out.

Although hospital admissions for food-induced anaphylaxis increased 6% per year, or three-fold from 1998 to 2018, the case fatality rate (fatalities as a percentage of hospital admissions) for food-anaphylaxis more than halved, from 0.7% to 0.3% during this period.

With the greatest fatality rates seen in teenagers, it is estimated that there are fewer than 10 fatalities a year due to food-induced anaphylaxis in the UK.

As to the question raised above about allergens, a total of 66 deaths were reported in children in the period under review with 14% of these caused by peanuts, 9% by tree nuts but more than a quarter — 26% — by cow’s milk.

“An increased awareness amongst food businesses and the general public regarding food allergy-related to peanut and tree nuts, rather than to cow’s milk, could be a factor here,” the FSA speculates.

Alternatively, it could be that there is an increased chance of exposure to cow’s milk that could cause severe allergic reactions, given its wide presence in the western diet.

Research into the data split question has revealed that, while there was a male predominance in food-related anaphylaxis admissions prior to puberty, this was reversed from age of 15 onwards.

“Most scientific research suggests that females in adolescence and adulthood have a higher anaphylaxis hospital admission rate than males,” the FSA said. “The reasons for this trend are still not clear, but it is probably linked to a combination of genetic, hormonal and environmental factors.”

Details of its research programmes can be found on the FSA website.