Scientists now believe that maternal exposure to pathogens prior to pregnancy can influence infant health and permanently alter offspring immunity by programming their immune system.
[Editor's Note: Welcome to #itsscience, where we break down the science behind the hard stuff that keeps you up at night—and the beautiful moments that leave you breathless.
As Motherly's Contributing Editor, Anne-Marie Gambelin is a Founding Team member, working on special projects, writing science features and Motherly essays. She launches our new column to provide evidence-based explanations that give you the why behind the mysteries of motherhood.]
The advantages of breastfeeding have been well-documented throughout the years—mamas know that breast milk can transfer antibodies to their baby, providing protection against infection, and that drinking mama's milk is one of the best ways to prevent illness in the first two years of life.
We've believed that this protection ended when breastfeeding ended. But new research has shown that the transfer of immunity might extend beyond the duration of breastfeeding, possibly even for life.
An international team of scientists, led by researchers at the University of Cape Town, found that infant mice that were breastfed by a mother with a worm infection before getting pregnant acquired lifelong protection against the disease. Historically, it's been thought that immunity was transferred by a mother's antibodies, but this research demonstrates that immunity could be passed on to infants by the transfer of immune cells through breast milk, completely independent of antibodies.
So what does this mean?
Unlike antibodies, which are made of proteins and used by the immune system to neutralize bacteria and viruses, immune cells patrol for problems by circulating in the bloodstream. They also divide and so remain ever-present—meaning they can remain in baby's body for years to come.
Scientists now think that maternal exposure to pathogens prior to pregnancy can influence infant health and permanently alter offspring immunity by programming their immune system. In the future, this could lead to the design of new vaccines that will be able to be given to a mother to transfer long-term immunity to her children through breast milk.
Bottom line: Breast milk is magical in even more ways than we know.