Mom’s Saliva May Boost Infants’ Immune Systems

By Kim Smiley

A recent study found that “cleaning” a baby’s pacifier by sucking on it may actually have some lasting health benefits.  Researchers determined that babies given pacifiers exposed to their parents’ saliva developed fewer allergies.  It’s still not clear whether the benefits come from the actual oral cleaning of the pacifier or if this was just a marker of parents who had a more laid back approach to cleanliness, but scientists are finding increasing evidence that some exposure to more microbes early in life results in fewer allergies.

A Cause Map, a visual format for performing a root cause analysis, can be used to illustrate this issue.  A Cause Map intuitively shows the causes that contributed to an issue as well as the cause-and-effect relationships between them.  In this example, researchers found that infants whose parents cleaned their pacifiers by sucking on them, rather than by boiling or rinsing with tap water, had lower rates of eczema, fewer signs of asthma and smaller amounts of a type of white blood cell that rises in response to allergies.  The key seems to be that saliva contains traces of the parents’ gut microflora.  The infant’s immune system is stimulated by this exposure to their parents’ microflora and this seems to help prevent allergies, which are caused by the immune system responding to harmless inhaled or ingested proteins.  The study also found that children who are delivered vaginally develop fewer allergies than those who are born via cesarean, which limits exposure to bacteria during birth.

These findings are important because the percentage of the population in industrialized nations suffering from allergies has risen rapidly in the 20th century.  Currently, about a third of the children in affluent countries are affected by allergies.  Studies, such as this one, are being done to try and determine what is causing the increase in allergies but the causes are not definitively known yet.  Circumstantial evidence seems to point to lack of exposure to microbes in early childhood as a risk factor.  This study was relatively small and more research on a larger scale will need to be done, but it is beginning to seem that children who get a little dirty and put a few questionable things in their mouths actually benefit from the exposure.

So if you had a mom who cleaned stuff (and you…) with her spit, you have one more reason to thank her this Mother’s Day.  Or if you were that type of mom you have one less reason to feel guilty.

Check out our previous blog – Amish have few allergies