About six per cent of children aged three and under have a food allergy. At this age, signs your baby might have an allergy can include skin reactions and respiratory or intestinal symptoms like hives, itching, coughing, vomiting, diarrhoea and blood in the stool. It’s possible for babies to have allergic reactions to foods before they’ve eaten them, as they can develop allergies to the foods their mother eats through her breast milk – most commonly milk and dairy products, peanuts and shellfish. Once babies start on solids they can develop allergies to other foods. Introducing new foods one at a time will make it easier to work out which food is responsible for a reaction if an allergy does develop.