Recently, the Center for Maternal and Child Health of the Chinese Center for Disease Control and Prevention (CDC) released the research results of the “Epidemiological Survey of Allergy in Infants and Young Children in Urban Areas”. Allergic diseases have been listed by the World Health Organization as one of the most serious public health problems in the 21st century. Why do allergies occur in infants and young children? What are the relevant factors? First, the baby’s own immature development The baby’s intestinal development is immature, the intestinal flora is not balanced, and the baby’s intestinal tract still has gaps, which are easily exploited by allergens and enter the bloodstream from the intestinal gaps, causing allergies. The immature development of the immune system of newborn babies, the external environment will produce an incorrect immune response, is also a key factor in the occurrence of allergic diseases. Second, genetic factors Allergies have a strong heredity, if both parents have no history of allergies, the baby’s risk of allergies is 15%, if one parent has a history of allergies, the baby’s risk of allergies increases by 20-40%, if both parents have a history of allergies, the baby’s risk of allergies is as high as 60%-80%. Cesarean section Cesarean section is a sterile birthing process that is not conducive to the activation and maturation of the baby’s immune system. A large number of clinical studies have shown that for cesarean section babies without a family history of allergy, their risk of allergy increases by 23%, while for cesarean section babies with a family history of allergy, their risk of allergy is three times higher. Other environmental factors There are many different environmental factors that can cause allergies. Mothers-to-be exposed to second-hand smoke during pregnancy, taking allergy-causing drugs, contacting pollen, eating allergy-prone foods, etc. may induce postnatal allergies in babies. Allergies can also be triggered by feeding babies with regular formula too early after birth, adding allergy-prone foods too early, inhaling second-hand smoke, and being exposed to allergy-causing substances such as dust mites in the environment. It is worth mentioning that excessive use of detergents (leave-on hand cleaners, wet wipes, etc.) makes babies lack exposure to microorganisms at an early age, which is not conducive to inducing the development of their own immune system. Moreover, disinfectants, if ingested into the stomach, will also kill the flora in the intestinal tract, causing babies to develop illnesses they should not have such as allergies and anaphylactic disorders. Take action and start our defense against allergies!