The greatest threat to the health of the vocal folds is smoking.
Vocal abuse and its consequence of vocal nodules can be a major problem for young singers. If they have not learned proper techniques, they will often require more intensity to sing than is typically necessary and healthy for the folds. Tragically the drive to keep performing eventually ends in the inability to keep singing at all.
The greatest single threat to the vocal folds, however, is smoking! The caustic nature of cigarette smoke with it cyanide, and many other poisonous gases acts to suppress the immune system.
This in general creates more frequent sicknesses and slower healing processes, and eventually a very high risk for cancer of the larynx. What may be worse to some people, of course, is that smoking causes deep creases in our favorite passport--the face.
The good news about laryngeal cancer is that it is easily detected. The pitch of the voice typically drops noticeably which eventually catches the patient‰s and the doctor‰s attention.
NOTES: See some of the benefits of smoking.