Nail-biting is a bad habit, but unlike scratching genitals (another bad habit that most men practiced), biting nails and fingers can be dangerous to health.
Besides you will annoy all around, nail biting entering the body and a pile of dirt. Because nail biting is an unconscious act, we will certainly not make sure that our hands are clean or dirty, and you put them in your mouth and when they are full of bacteria, among which are found some hazardous to health.
Maybe you already caused stomach pain, nausea or diarrhea by nail biting, but you did not even know what the cause was.
Under the nail can also be found salmonella, and E. coli, which you will enter into the body that way.
In addition, viral warts on fingers can be transferred to the area of the face, a constant nail biting can do damage to the teeth and gums.
Look how dirty nails look under a microscope, and once again consider whether you can keep your nails: