news for parents who have struggled to get their kids to take
their fingers out of their mouths: nail biting and
thumb-sucking might have health benefits.
habits, scientists found in a recent study, were linked to
less risk of allergies to a host of things — including dust
mites, animals, and common molds.
findings support what’s known as the "hygiene
hypothesis," or the idea that a too-clean environment is
to blame for the rise of children’s allergies. According to
the hypothesis, children who are exposed to some germs early
in life develop immune systems that can tolerate contact with
research has shown that children who own pets, attend day
care, live on a farm or have many siblings tend to be less
prone to allergies. One study found that babies whose mothers
cleaned their pacifiers by sucking the object clean were less
at risk for asthma.
nail biting and thumb-sucking study, about 1,000 children from
New Zealand participated and were assessed periodically,
starting at age 3.
skin-prick test was used to see if there was an allergic
reaction to common allergens. The nail biters and
thumb-suckers were significantly less likely to test positive
for many allergies when they were 13 and 32 years old. But
their oral habits didn’t have any bearing on their risk of
having asthma or hay fever, the New Zealand researchers noted.
course, there are other concerns around nail-biting and
thumb-sucking, among them: gum injury and social stigma.
Acknowledging these concerns, the authors said that they are
not making any recommendations.
we do not suggest that children should be encouraged to take
up these oral habits," they wrote, "the findings
suggest that thumb-sucking and nail-biting reduce the risk for
developing sensitization to common (allergens)."
findings appear in a recent issue of the journal Pediatrics.