Allergies have become a matter of great concern, and according to the WHO, allergies have become the top six diseases in the world, with 20% of the world’s population suffering from allergies. Many babies have mild to moderate allergies, with dermatitis appearing on the face or body. Parents often don’t care and think it doesn’t matter, a little eczema in their child is not a problem. Other parents do not know that their children are allergic and think that it is only caused by heat. Only when they see their children scratching their bodies or even scratching their skin, do they understand that their children are “itchy”! In fact, children’s allergies are much more than just itchy. The “little” allergy is one of the most common chronic diseases. It starts in infancy and can last a lifetime. It’s incredible to say that it adds to the burden of disease on society, but it can certainly affect an individual’s quality of life, and even their lives. Although medicine and technology are quite advanced, the pathogenesis of allergies is not yet fully understood. Many allergies such as asthma and allergic rhinitis can be controlled and may not be cured, but they can be prevented. What foods are likely to cause allergies? Foods that tend to cause allergies include milk, eggs, peanuts, nuts, fish, soybeans, wheat, etc., which account for about 95% or more of food allergies. More foreigners are allergic to wheat and nuts, while fewer domestic people are allergic to wheat and nuts. There are also people who are allergic to cucumber, lettuce, eggplant, etc., but they belong to a very small minority. The most common food antigens that infants are exposed to and allergic to are cow’s milk, from which most ordinary milk powder is derived. Since goat milk and cow milk have cross-protein antigens, children who are allergic to cow milk are likely to be allergic to goat milk as well. Severe allergies may lead to malnutrition, significant wasting, and delayed or lagging growth in babies. Generally, parents can easily notice eczema on a child’s face, but some allergic children tend to affect the intestinal tract, leading to congestion of the intestinal mucosa, etc., resulting in diarrhea or constipation, which affects the absorption of nutrients. Allergic diseases may run in families Allergies may also be passed on to the next generation. Some studies suggest that if one parent is allergic, the chances of the child suffering from allergies are 20-40%; if both parents have allergies, the chances of the child suffering from allergies are 40-60%; if both mom and dad have the same kind of allergy manifestations such as asthma, the chances of the child suffering from allergies will further increase and can reach 50-80%. Therefore, if the parents themselves are allergic and the child already has allergies, it is likely to be genetically related, and if there is no baby yet, beware that the baby may develop allergies. Environmental factors affecting allergies There are many environmental factors that cause allergies, such as second-hand smoke, indoor insect mites, pets, drug use (e.g. antibiotics, certain hormones), premature exposure to protein foods, etc. Some foreign studies have shown that cesarean delivery increases the risk of allergies in babies at high risk for allergies by up to three times. Why does cesarean delivery increase the risk of allergic diseases in babies? It may be due to the fact that cesarean delivery is not exposed to maternal flora as direct delivery, the use of antibiotics after cesarean delivery, the baby’s possible exposure to pathogenic bacteria in the hospital yard, and the delayed breastfeeding due to cesarean delivery. These factors may lead to delayed colonization of healthy intestinal flora in cesarean-born babies, which only approaches the level of naturally delivered babies after 180 days. How to prevent baby allergy 1. Breastfeeding is the best allergy prevention measure (1) Hypoallergenicity of breastfeeding The proteins derived from breastfeeding are homogeneous proteins, and the infant’s immune system is not easily sensitized. Breast milk contains protein fragments (peptides) that are hypoallergenic, but can gently stimulate the infant’s immune system, induce immune tolerance and reduce the occurrence of allergies. (2) Flora in breast milk Breast milk contains normal flora that colonizes the baby’s intestine and can perform immunomodulatory functions. (3) Cytokines unique to breast milk Breast milk contains a large number of cytokines, such as TGF-β, CD14, IL-6, IFN-γ, which can regulate immunity and thus reduce the risk of allergy in babies. (4) Immune substances in breast milk Contains IgA, a secreted immunoglobulin, which binds to macromolecules and attaches to the surface of the intestinal mucosa, preventing them from passing through the intestinal mucosa. The amazing thing about humans – probiotics in the mother’s body run into the fetus or baby: the flora of the mother’s intestine is able to reach the baby’s intestine through certain pathways (e.g. immune cells engulfing bacteria, after a brief period of bacteremia) via the placenta and amniotic fluid. Breast milk is not sterile, but contains a certain amount of probiotics that are passed to the baby through the milk, which is the magic of human beings. 2, probiotics to prevent allergies in babies A large number of studies have revealed that some probiotics have the effect of preventing allergies. They can adjust the composition of the intestinal flora, so as to play the function of regulating immunity, so that immunity maintains a certain balance, thus achieving the role of allergy prevention. However, not all probiotics have such an effect, nor can yogurt or drinks containing probiotics in general achieve the effect of treating or preventing allergies. Only a specific probiotic preparation can have this effect, such as Lactobacillus rhamnosus, which can be used to treat and prevent allergies in infants and children. Some studies have shown that probiotics, whether given in postnatal breast milk itself or fed directly to infants, are effective in preventing the early onset of allergic disease in children at high risk of allergy, especially atopic dermatitis, and that this preventive effect can continue until the child is 4 years old. Of course, more research is needed to determine whether it is worth recommending probiotic supplementation for prevention. Research is research, and there are no authorities that recommend probiotic supplementation for allergy prevention.