Health

Thumb-Sucking And Nail-Biting May Lead To Fewer Allergies Later In Life

Good news for all of those parents worried about their thumb-sucking, nail-biting children: There may be a bright side. These rather gross habits may actually benefit your child.

A new study published in the journal Pediatrics indicates these habits—while stress-inducing for parents—may lead to fewer allergies later in life.

The study looked at the nail-biting and thumb-sucking habits of children at ages 5, 7, 9 and 11 years old. These same participants were tested for allergic reaction to common allergies including dust mites, dogs, cats and common molds at age 13 and then again at age 32. Thirty-one percent of the participants were labeled “frequent” nail biters or thumb suckers (or both) at one or more of those ages.

Those who frequently sucked a thumb or bit their nails were significantly less likely to have positive allergic skin tests at 13 and again at 32. Children with both habits were even less likely to test positive for allergies.

The study originated from questions surrounding the hygiene hypothesis, which suggests a link between allergy-related or “atopic” diseases, such as asthma or dermatitis, and a lack of exposure to various microbes early in life.

Robert J. Hancox, one of the authors of the study, told The New York Times, “The hygiene hypothesis is interesting because it suggests that lifestyle factors may be responsible for the rise in allergic diseases in recent decades. Obviously hygiene has very many benefits, but perhaps this is a downside. The hygiene hypothesis is still unproven and controversial, but this is another piece of evidence that it could be true.”

Some exposure to germs, the theory suggests, may help a child’s immune system to fight disease. So does this mean we should encourage our children to suck their thumbs well past the socially accepted age? Not necessarily.

The American Dental Association warns against thumb-sucking once permanent teeth erupt because it can cause problems with teeth alignment and proper mouth growth. The important thing is to talk to your child’s pediatrician or dentist about how best to work with your child.

Photo by various brennemans