The Bad Part!

Now we come to the bad side of Hookah-smoking,
the HEALTH EFFECTS!
All studies of Hookah effects don't match each other.Some say its good while some say its bad.
In my view it depends upon the smoker and the amount of smoking.
Occasional smoking hasn't caused any bad-effects to someone I know.
Although any type of smoking is always in some proportion harmful.
It also depends upon the Set-up of the hookah.There are many major mistakes that newbies make like-Using barbecue coals for hookah which can even cause death.
Here are some studies on the effects of hookah that I found on the net:

Each hookah session typically lasts more than 40 minutes, and consists of 50 to 200 inhalations that each range from 0.15 to 0.50 liters of smoke.^[27][28] In an hour-long smoking session of hookah, users consume about 100 to 200 times the smoke of a single cigarette^[27]; in a 45-minute smoking session a typical smoker would inhale 1.7 times the nicotine ^[29] of a single cigarette. The water used to filter the smoke does not remove all the harmful chemicals.^[29]

A study on hookah smoking and cancer in Pakistan was published in 2008.^[26] Its objective was "to find serum CEA levels in ever/exclusive hookah smokers, i.e. those who smoked only hookah (no cigarettes, bidis, etc.), prepared between 1 and 4 times a day with a quantity of up to 120 g (the average bowl holds 30g) of a tobacco-molasses mixture each (i.e. the tobacco weight equivalent of up to 60 cigarettes of 1 g each) and consumed in 1 to 8 sessions". Carcinoembryonic antigen (CEA) is a marker found in several forms of cancer. Levels in exclusive hookah smokers were lower compared to cigarette smokers although the difference was not statistically significant between a hookah smoker and a non-smoker. Also the study concluded that heavy hookah smoking (2–4 daily preparations; 3–8 sessions a day; 2 to 6 hours) substantially raises CEA levels.

One Should take these studies in view before trying on Hookah