If you’ve ever attended a tense sports game or been nervous about giving a presentation at work, chances are you’ll almost certainly have tried biting your fingernails. It’s a habit that is observed in people of all ages and to help shed some light on the reasons why people take comfort in chomping away on their nails, The Focus spoke with Silja Litvin, a psychologist and founder of the mental health platform PsycApps. The psychological reasons why people bite their nailsEven though research has shown that thousands of bacteria live under our fingernails, millions of people from around the wor…