9 Bad Habits That Science Says Are Good For You
9. Biting Your Nails
If you're a nail biter, you'll probably have been told that it's dirty and a disgusting way to introduce bacteria into your system.
Incidentally, it is for this exact reason that nail biting might actually be good for you.
A study in Pediatrics found that kids who bit their nails or sucked their thumbs were less likely to develop asthma and allergies and had generally stronger immune systems. It could be that the constant stream of bacteria being introduced into the body was giving the immune system plenty of exercise as it had to ward of the onslaught of infection.
This said, it is by no means advisable to take up the habit, there are plenty of downsides, but if it's a habit you already have then you can take some comfort from your mad powerful immune system.