Lesser-known food allergens are actually behind many serious reactions

Around one in seven cases of life-threatening allergic reactions seem to be caused by foods not typically labelled as potential allergens on a product’s packaging, prompting researchers to argue policies around this need to change.

Food allergies are becoming more common, but many official allergen lists have not been updated in years. For instance, the European Union’s mandatory labelling of foods list states the presence of 14 food allergens, like peanuts and soya, must be made clear on products, but is based on data from 2011.

To understand the lesser-known triggers, Dominique Sabouraud-Leclerc at Centre Hospitalier Universitaire de Reims in France and her colleagues analysed 2999 cases of food-induced anaphylaxis – a life-threatening reaction – voluntarily reported by doctors to the Allergy-Vigilance Network, which collects data from French-speaking countries, between 2002 and 2023.

They were specifically looking for emerging food allergens, which they defined as any foods that were not on the European mandatory labelling list, but which were individually responsible for at least 1 per cent of cases.

The team found goat milk, sheep milk and buckwheat triggered 2.8 and 2.4 per cent of cases, respectively. These were followed by peas and lentils, alpha-gal – a sugar that can trigger an allergy to red meat and other mammalian products – pine nuts and kiwi, which each set off between 1 and 2 per cent of incidences. Apples and beehive products like edible pollen, honey and royal jelly caused 1 per cent of cases.

Overall, emerging food allergies were responsible for 413 – roughly 14 per cent – of the reported cases.

In terms of reaction severity, goat and sheep cheese provoked particularly dangerous reactions, especially in young boys, causing two deaths. Recurrent reactions and hidden exposure – like in a sauce or as a thickener – were most common with goat or sheep milks and cheeses, followed by peas and lentils, buckwheat and pine nuts.

Off the back of this, the team has suggested these four food types be added to the list of mandatory warning labels in Europe, which states the presence of these ingredients must be emphasised, for instance, by being written in bold on the packaging.

“Our main goal is to protect allergic consumers and ensure they have access to clear information,” says Sabouraud-Leclerc. “This is all part of good patient care: diagnosis, education, emergency kits and knowing how to read labels.”

While the data came mainly from France, Belgium and Luxembourg, the results would probably be applicable to other countries, with some differences in prevalence depending on local cuisine, says Sabouraud-Leclerc. “If we manage to update the EU list, that might inspire other countries to follow, kind of like a snowball effect,” she says.