A study of 500 children found that food sensitivities became more common and changed type between their first and fifth birthdays, highlighting the limits of relying on a single early allergy test.
A new study suggests that food allergy risk in young children is not static, but shifts markedly between the ages of one and five. Researchers found that both the number of children showing sensitivity to foods and the specific allergens involved changed over that period, underscoring the need for ongoing monitoring rather than treating an early test result as definitive.
According to the report in the journal Allergy, about 25% of children in the study had sensitivity to at least one food by their first birthday. By age five, that figure had risen to 40%. The research team analysed blood samples from 500 mother-child pairs taking part in a long-term Canadian study, testing for 300 allergen extracts and components at ages one and five.
The pattern of allergens also shifted with age. Egg and peanut were among the main concerns in infancy, but by age five children were showing more sensitivity to tree nuts including cashew, hazelnut, walnut and pistachio. Sensitisation to environmental allergens such as cats, dogs, dust mites and grass pollen also became more common as children got older.
Thomas Eiwegger, head of paediatric and adolescent medicine at University Hospital St. Pölten in Austria and the study’s senior author, said in a news release that a positive allergy test in a very young child should not be treated as the final word. He said doctors need to know whether a sensitivity persists, fades or appears later, because that information can affect how risks and treatment options are discussed with families.
The study also found that allergy patterns can go the other way. Roughly one in four children lost sensitisation to peanut, tree nut and sesame components as they aged, suggesting that some early reactions may not last. That matters for treatment planning, the researchers said, because the approach may differ depending on whether a child’s sensitivity is newly detected, persistent or disappearing.
The findings fit with earlier research showing that food allergy profiles can evolve throughout childhood and adolescence. Studies published previously have found that milk and egg allergies tend to be more common in younger children, while peanut and tree nut allergies become more prominent later in childhood. Taken together, the evidence points to a condition that can change substantially as children grow, rather than following a single fixed path.
Disclaimer: This content is for informational purposes only and is not intended to be a substitute for professional medical judgment, advice, diagnosis, or treatment.
