Effect of maternal nutritional status on immunological substances in human colostrum and milk.

Substances in colostrum and breast milk confer significant disease resistance to the breast-fed infant. The influence of maternal nutritional status on both immunological and nonimmunological milk factors was studied in a group of 23 Colombian women during the first 2 months of lactation. Maternal malnutrition was characterized by significantly lower weight/height ratio, creatinine/height index, total serum proteins, serum albumin, and serum IgG and IgA. The colostrum of malnourished mothers contained only one-third the normal concentration of immunoglobulin G and less than half the normal level of albumin. Significant reductions in colostrum levels of IgA and the fourth component of complement (C4) were also observed in the malnourished group. No differences were observed in colostral concentrations of lysozyme, C3 complement, or IgM. Titers of antibody in milk directed against respiratory syncytial virus were not influenced by maternal nutritional status. The differences noted above tended to disappear in mature milk, concomitant with improvement in the nutritional status of malnourished mothers during the first several weeks postpartum. We conclude that the protective qualities of colostrum and milk may be significantly influenced by maternal nutritional status.