This Gross Childhood Habit May Have An Unexpected Benefit

Photographed by Tom Corbett.
You were always scolded for biting your nails as a kid, but little did your parents know that this (admittedly pretty gross) habit could benefit you in the long run. A new study published in the journal Pediatrics suggests that people who bit their nails and sucked their thumbs as children may have fewer allergies as adults. Related: 10 Terrifying Reasons To Stop Nail Biting — For Good! Researchers studied a pool of 1,037 children in New Zealand, tracking their nail-biting and thumb-sucking habits from the age of 5 to 11. Once the children reached their teen years, the researchers began testing them for common allergies, including dust mites, grass, cats, and dogs. The study continued into the participants' 30s. In the end, the researchers found that the people who sucked their thumbs or bit their nails with greater frequency were much less likely to have allergies as teens or adults. In fact, only 31% of those who had both habits tested positive for allergies. "Our findings are consistent with the hygiene theory that early exposure to dirt or germs reduces the risk of developing allergies," lead researcher Malcolm Sears, PhD, said in a press release. In other words, the kids who put their (bacteria-ridden) hands in their mouths more often grew accustomed to common types of germs before they develop sensitivities or allergies to them.
Related: 10 Easy Ways To Boost Your Immunity Although this is an upside to the kinds of habits that children often end up adopting no matter what, Michael Shapiro, MD, medical director and founder of Vanguard Dermatology, tells Shape that the risks of nail-biting still outweigh the benefits. "Bacteria often gets stuck under the nails, and can then be transferred to the mouth, causing infections of the gums and throat," he says.
Click through to Shape for more info on staying healthy, long-term. (Shape) Related: How To Fight Cold & Flu Germs (The *Right* Way)

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