Breast milk and colostrum are the first feeding sources for a child, providing nutrients, growth factors and immunological components, which are crucial for the newborn's correct development and health. Length of exclusive breastfeeding and time of solid foods introduction is a key factor that may influence allergy development. There is an emerging evidence of a relationship between breastfeeding, milk composition and lower risk of chronic diseases, such as diabetes, obesity, hypertension and allergies. This review examines current evidence regarding humoral and cellular characteristics of breast-milk, and potential role of environment, maternal diet and breastfeeding on the allergy development in children.