Do you bite your nails? Why?

I used to bite my nails a lot when I was growing up, and I never could figure out why -- until I reached my senior year of high school. My nails started growing and I wasn't biting them at all, and the only change in my life was that I wasn't in math class! I couldn't believe it. In college I started biting my nails again during my calculus classes, and after I had completed those I was once again a non-nailbiter. I have noticed now that I do it mostly when I'm concentrating really hard or a little more stressed and consumed by what I'm doing. I still blame a lot of it on math, though.

I bite my nails if im scared or im nervous over something. Or my hubby is questioning me and i feel scared to answer. Sometimes if i cant look to him straight into his eyes i bite my nails..to relax myself.

When I was in School, I used to bite my nails when I was tensed up. Now I have given up that habit and I peel off the dry skin on my lips when I am in deep thinking.