Patrick Guilfoile: One bad habit that may be good for baby
Babies seem to have an uncanny knack of putting disgusting things in their mouths, whether a “gift” left behind by an animal, used chewing gum or a previously used facial tissue. Some parents may be setting an example for their babies by “cleaning” their child’s pacifier in their mouths.
Yet, in spite of the fact that the mouth is one of the most bacterially contaminated regions of the body, these parents may be doing the right thing.
Newly reported research suggests babies whose parents “clean” their pacifier by putting it in their mouths are less likely to develop allergies and rashes. Researchers studied 184 full-term babies born in one hospital in Gothenberg, a city located on the west coast of Sweden, near Denmark. In 80 percent of the families, at least one parent had allergies. The investigators interviewed parents when their babies were six-months-old. Among the questions asked was whether they ever cleaned the baby’s pacifier by sucking on it. (In this study, about half of the parents reported that they at least occasionally cleaned their baby’s pacifier in their mouths.)
At 18 and 36 months, the researchers interviewed the parents again, and took blood from the toddlers to find out whether some characteristic features of allergies were present. In addition, scientists took saliva samples from some of the infants, and analyzed the saliva to determine what microbes were present. A pediatrician also examined the children for signs of asthma, rash (eczema), and allergies.
The investigators found that, in families where the parents cleaned the baby’s pacifier in their mouths, the children had a significantly reduced risk of allergy and rash. Scientists also provided evidence that the microbial flora in the mouth differs in children whose parents didn’t suck on pacifiers to clean them, as compared to parents who did suck on the pacifiers. These differences in oral microbes could be responsible for the differences in the degree to which the babies develop allergic reactions.
This study provides more evidence for something called the “hygiene hypothesis,” an idea proposed by David Strachan in 1989, which states that allergies and related conditions might be the result of limited exposure to microbes in our environment. The hypothesis asserts that this lack of exposure to microbes causes our immune system to run amok, leading to allergies and other autoimmune conditions.
So, when it comes to pacifiers, it seems that we might not be doing our children any favors if we try to keep them as germ-free as possible. It might end up that a little dirt and saliva-swapping is just what the doctor ordered.
More information is available in the article “Pacifier Cleaning Practices and Risk of Allergy Development.” by Bill Hesselmar, Fei Sjöberg, Robert Saalman, Nils Åberg, Ingegerd Adlerberth and Agnes E. Wold in Pediatrics; originally published online May 6, 2013
— PATRICK GUILFOILE has a Ph.D. in bacteriology and is the associate vice president at Bemidji State University.