Actually the hookah by its self is fine, as long as you put noting in it. The pipe in which you place shisha tobacco in order to smoke it is called a hookah.
Smoking shisha tobacco is no different from other tobaccos. It can cause damage to the lungs, heart, bones and other body parts just the same as cigarette tobacco will.
And just like tobacco, shisha contains tar, nicotine and carcinogens. The carcinogens of course are the chemicals which is one of the main causes of cancer.
Anyone who smokes it can develop both lung and mouth cancer from using shisha. It is also responsible for the damage for the dangers of second hand smoke. The only real difference is that people who use a hookah with shisha tobacco tend to not use quite as much as those who smoke pipes or cigarettes.
So draw your own conclusion from the above info.