Health Benefits of Thumb-Sucking and Nail-Biting

A scientific study conducted not while ago suggests that kids who regularly bite their nails or suck thumbs are more resistant to allergies. The scientists behind this study claim that the reason is simple – those who are exposed to a small number of germs, are able to make their immune system stronger (hygiene hypothesis).

For this purpose, they have tested more than one thousand people in New Zealand and checked their health condition from time to time. The participants were between 5 and 32 years old. The final results were clear – nail-biting as well as thumb-sucking was able to keep the participants safe from many types of allergies.

However, this practice didn’t have any effects on the possibility to develop hay-fever or asthma. They have checked the participants for their habits at age 5, 7, 9 and 11 and they were tested for different types of allergies at 13 and 32.

It turned out that about 35% of the children were biting their nails or sucking their thumbs frequently and these kids had drastically lower chances of experiencing allergies when they turned 13.

The chances of these kids to experience allergies related to dogs and cats or dust mite were about 35% lower compared to kids who were not biting their nails or sucking their thumbs.

The team of scientists from the University of Otago in Dunedin, New Zealand, has confirmed that this protection doesn’t go away even in late adulthood.

According to one of the team members, Professor Malcolm Sears, who actually works at the McMaster University in Canada, scientists are not supporting and encouraging these habits, but the fact is that they bring some benefits too.

In addition, some experts point out that there were other similar studies in different countries that have confirmed that the environment and gut microbiota are interconnected and that they are forming the chances of developing food allergies.

Having older siblings, pet dogs and cats and living in the countryside are strong environmental influences that can contribute to the emergence of allergies and that’s why these people should be careful.