• There may be some good news for nail-biting adults! (Getty Images)Source: Getty Images
Gross, but true - a new study links childhood thumb-sucking and nail-biting to fewer allergies in adulthood.
By
Jody Phan

13 Jul 2016 - 1:40 PM  UPDATED 13 Jul 2016 - 3:22 PM

It’s the good news nail-biters have been waiting for. According to a new study published in Pediatrics journal, those “bad habits” over the years may have played a role in the prevention of allergies.

The study was based on the hygiene hypothesis, which states that early exposure to bacteria and germs prepares the immune system for bigger fights against more serious infections and diseases later in life.

Researchers from New Zealand and Canada followed a group of about 1,037 people from birth until age 32 and assessed their thumb-sucking and nail-biting habits at ages five, seven, nine and 11, and tested them for allergies at age 13 and 32.

Children who had at least one of the habits were 40% less likely to develop allergies as adults.

About half of the people who didn’t suck their thumbs or bite their nails in childhood tested for allergies at age 32.

Children who had at least one of the habits were 40 per cent less likely to develop allergies as adults, and children who did both showed the lowest rate of reaction to allergens.

Although adults who sucked their thumbs or bit their nails as kids were less likely to be sensitive to allergens, the study did not find any links between the habits and lowered risk of asthma or hay fever.

That being said, researchers aren’t exactly recommending parents to coach their children to bite their nails or suck their thumbs for the sake of lowering their risk of allergy.

Although adults who sucked their thumbs or bit their nails as kids were less likely to be sensitive to allergens, the study did not find any links between the habits and lowered risk of asthma or hay fever.

“Many parents discourage these habits, and we do not have enough evidence to (advise they) change this,” said Dr. Robert Hancox, the study’s lead author and professor at the University of Otago in New Zealand.

“We certainly don’t recommend encouraging nail-biting or thumb-sucking, but perhaps if a child has one of these habits and (it) is difficult (for them) to stop, there is some consolation in the knowledge that it might reduce their risk of allergies.”

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