The finding that there is a strong association between water-pipe (shisha) smoking and cancers of the head and neck, oesophagus and lungs, as revealed in a comprehensive study by researchers at Weill Cornell Medicine-Qatar (WCM-Q), should be an eye-opener.
While the risks of smoking cigarettes are well known, those of shisha smoking remain poorly understood and hence the significance of the study which strikes at the very roots of a popular misconception that the widely accepted practice is safe. 
Entitled “Cancer risk in water-pipe smokers: a meta-analysis” and published in the International Journal of Public Health, the study was led by WCM-Q’s Dr Ravinder Mamtani and Dr Sohaila Cheema. A sophisticated meta-analysis technique was used to review 28 published scientific studies and examined the relationship between shisha smoking and various forms of cancer, including cancer of the head and neck, oesophagus, stomach, lung and bladder.
Dr Mamtani, associate dean for Global and Public Health at WCM-Q, said the need for such a study had become urgent in recent years owing to the surge in popularity of shisha, especially among young people and women. 
Shisha smoking is significantly different because the smoker generally inhales far more smoke, smokes for longer, and there are different concentrations of toxins than in cigarette smoke, he explained.
Dr Cheema, director of Global and Public Health at WCM-Q, pointed out that shisha smoking is a very social act in the Middle East. 
A shisha smoking session can expose the user to up to 50 litres of smoke over a 45-minute use period, compared to around one litre of smoke that is consumed by someone smoking a cigarette over about five minutes. 
Shisha smokers are exposed to tar, addictive nicotine, carbon monoxide, and other harmful substances at similar levels and sometimes greater levels than cigarette smokers. 
According to Dr Cheema, WCM-Q’s analysis of the existing studies points to a clear association between shisha smoking and several forms of cancer and people need to be aware of this so that they can make informed choices about whether they smoke or not. 
As Dr Mamtani pointed out, governments around the world have taken steps to reduce cigarette smoking in their populations through measures such as public health campaigns, tax policy, creating smoke-free areas and passing laws about what can be displayed on packaging. Until now, shisha smoking has managed to escape many of these measures. 
Unpublished WCM-Q data indicates that among adolescents in Qatar aged 15-18 years, 13% had tried cigarettes and 22% shisha. Among college students in Qatar, 27% said they were regular or social cigarette smokers, and 32% regular or social shisha smokers. 
As Dr Mamtani urged, it is time for more studies about shisha smoking, more public awareness of its risks and exploration of opportunities for public policy on this issue to protect public health.