Hookahs or hubbly bubbleus has become very popular among young people with little consideration for it's adverse health effects.
While it pales against the risk of smoking, scientist Chris Smith says you can catch infections from sharing a pipe.
Smoking is always bad. It is the worst thing you can do for your health. Smoking causes cancer but also causes heart disease and strokes. It takes a good ten years of your life.— Chris Smith, Naked Scientist
The second point, there are infections that can be spread by saliva. The common ones are things like Hepatitis B and more mundane things like Herpes Simplex virus that causes cold sores and the common cold. All these things go in saliva.— Chris Smith, Naked Scientist
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