McMaster University Feb 9 2026 A new study from McMaster University involving 2.8 million children around the world has revealed the most important early-life factors that influence whether a child becomes allergic to food. The study, one of the largest of its kind to examine food allergies, furthers our understanding of how allergies develop, concluding that a combination of genetic, environmental, microbial and social factors influence allergies, rather than a single cause. To come to their