Nail biters, thumb suckers may be less prone to allergies

By Laura Mize • Published: October 18th, 2016
Category: Health in a Heartbeat

Is your child a champion nail biter? Or maybe a thumb-sucker way past the toddler years. If so, you’ve probably had more than enough parental angst over these undesirable habits.

A new study suggests these bothersome behaviors may actually have some benefit.

Children in New Zealand who were nail biters or thumb-suckers at age 5 or older were about one-third less likely to have allergies than children who didn’t suck their thumbs or bite their fingernails. The findings were published in the journal Pediatrics.

Now comes the ironic part. Researchers suggest that the association between nail biting or thumb sucking and fewer allergies involves an increased exposure of the children to germs and dirt. It’s increasingly recognized that being too hygienic and clean, or too shielded from microbes, may be bad for the immune system.

Our immune systems need germ exposure, especially early on in life, to learn how to respond properly to foreign substances later in life. With too little germ and dirt contact, our immune systems can become sensitive and overreact to plants, food, pet dander and other things. This is one way allergies develop.

Thumb suckers and nail biters come into contact with plenty of germs. And perhaps because of it, their immune systems tend to avoid overreactions such as those that produce allergies.

However, the New Zealand researchers did also point out the risks associated with these two habits.  Excessive thumb sucking can cause teeth to grow in incorrectly. And nail biting can lead to infected skin around the nails.

But sometimes there’s a limit to what a parent can do. So, while you are trying to help your little one grow out of these habits, maybe it will help to also remember some of the potential benefits.