One in 20 people in Britain have a confirmed food allergy, research shows

One in 20 adults in Britain have a confirmed food allergy and almost a third have food insensitivities, the first study of its kind has found.

The Food Standards Agency (FSA) report found that 2.4 million adults (6%) had a clinically confirmed food allergy, with the most common allergy being to peanuts and tree nuts such as hazelnuts, walnuts and almonds. Many people also had allergies to fresh fruit, including apples. Milk and fish allergies were less common.

The FSA said the research showed that the rise of plant-based allergies was important to consider due to the increase in alternative diets.

About 30% of the thousands of respondents had symptoms of food sensitivity, where they experienced an unpleasant reaction after consuming a certain food. There are different types of hypersensitivity, including allergy, intolerance and celiac disease.

Previous figures suggest that around 1% to 2% of British adults have a food allergy. However, these figures come from FSA-funded studies in which individuals self-reported without clinical assessment.

A previous study conducted thirty years ago focused only on food intolerance and for several reasons, including the different methods used, the results were not comparable.

Professor Robin May, the FSA’s chief scientific adviser, said the latest report had made an important contribution identify how food allergies developed between childhood and adulthood, and provide insight into “links between certain foods and the persistence of allergies into adulthood.”

The report found that food allergies in children persisted into early adulthood and increased thereafter. About half of food allergies developed later in life, it turned out.

May said the research also showed “the rise of plant allergies affecting more and more people into adulthood”. This was important to consider as the food system had transitioned to plant-based diets and alternative proteins, he added.

The study found that foods such as peanuts are most likely to cause an allergic reaction. Many people had allergies to fresh fruit, including peaches and kiwis. These have been associated with allergies to birch pollen, also known as pollen-food allergy syndrome or oral allergy syndrome. Allergies to foods such as milk, fish, shrimp and mussels were less common.

May said: “The FSA remains committed to ensuring consumers have clear and accurate allergen labeling, supporting people in Britain living with food allergies. This report will help guide our future work on allergens to ensure everyone can enjoy food that is safe.”

During the first phase of the study, titled Patterns and Prevalence of Adult Food Allergy (PAFA), people were invited to complete a questionnaire and report all types of reactions they had ever experienced after eating. Some reported that their food sensitivities had been diagnosed by a doctor in the past, while others reported that they had never spoken to a doctor or physician about their symptoms.

When this was investigated further through a clinical assessment, it was estimated that approximately 6% of the adult population in Great Britain had a clinically confirmed food allergy.