5. Running a risk 跑步或运动时，鞋子不舒适，会对脚部造成伤害
Yes, exercise is good for you; but repetitive actions can hurt your feet, especially if you're not wearing the best footwear. Dancing – particularly in ballet toe shoes (See: Black Swan) is particularly hazardous for your feet, so dance with care.

Running, too, which causes the foot to be repeatedly pushed into the heel and toe, can cause bleeding under the nail. If that happens, the toe won't grow back normally – ever.

This is a common problem podiatrists see around marathons, says Dr. Yourner. If this (or any of the above foot problems) does happen, she urges, see a podiatrist as soon as possible. "Don't let your injury get to the point where the nail falls off," she warns.