A Review on the Dynamic Changes and Influencing Factors of Immunoglobulin Contents in Human Milk

Human milk provides adequate nutrition for infants’ early development and is rich in immunologically active substances, protecting infants against diseases before their own immune systems mature. Secretory immunoglobulin A (sIgA), IgM, and IgG, the major immunologically active substances in human milk, have been most extensively studied. The concentration and composition of Igs in human milk change with the lactation period, which is influenced not only by lactation stages (colostrum, transitional and mature milk) but also by the lactating mother’s living environment, dietary nutrition, gestational age, and other factors. This paper systematically reviews the concentrations and influencing factors of Igs in human milk from different countries and regions, with the aim of providing references for the in-depth research and application development of active components in human milk.