Increasing numbers of adolescents in the U.S. are gathering around hookahs — water pipes used to smoke flavored tobacco called shisha. The Monitoring the Future 2015 survey of 44,892 students found that past-year hookah use among 12th graders was approximately 20 percent. This makes it the third most common drug used, right behind alcohol and marijuana!

Smaller studies have found that 22 to 40 percent of college students had used hookahs within the past year.

The "anatomy and physiology" of hookahs: Although hookahs vary in size, shape and style, they all basically work the same way.  The shisha —  in flavors including apple, mint, cherry, chocolate, coconut, licorice, cappuccino and margarita — is placed in a small bowl at the top of the hookah. The bowl is covered with perforated tin foil or a metal screen. Hot charcoal is placed on top and heats the tobacco without burning it (electronic hookahs don't require charcoal to heat the tobacco).  With each of the user's inhalations through a hose, the vapor is pulled down to the water base.

Hookah smoking is typically done in groups, making it a social form of tobacco. Today, hookah cafés, bars and lounges are gaining in popularity around the world. Sometimes the legal smoking age is not enforced.

Is hookah use safe? People may think that hookah use is less harmful than smoking cigarettes.  They're wrong. Evidence shows that hookah smoking using charcoal-heated tobacco carries even more health risks than smoking cigarettes. Sometimes more is not better.

  • More exposure to toxic chemicals. Hookah smoke contains multiple toxic chemicals that come from both the heated tobacco and the charcoal. Hookah water does not filter these out. These toxins can cause:

  • More puffs…more harm: During a typical one-hour hookah session, a hookah smoker inhales about 200 puffs, compared with 20 puffs that the average smoker takes per cigarette. In other words, a 60-minute hookah session is equivalent to smoking 10 cigarettes.

  • More carbon monoxide (CO) exposure: Another "perk" of hookah smoking. Hookah cafés patrons are exposed to dangerous amounts of carbon monoxide (CO).  CO reduces the amount of oxygen that can be transported to the body's organs, including the brain. As hookah use has become more common, there are now case reports in the medical literature of hookah smokers needing treatment in hospital emergency rooms for "hookah sickness." Symptoms of CO poisoning include confusion and loss of consciousness.

  • More second-hand (hookah) smoke: Studies have found significant levels of toxic chemicals in the air of hookah cafés in the unhealthy to hazardous range according to Environmental Protection Agency standards.

  • More than hookah vapor may be shared: When people share a mouthpiece they have an increased risk of infections including hepatitis, herpes and tuberculosis.

Can people get hooked on hookahs? Yes, and there are no ifs, ands or "butts" about it. Hookah smokers (especially frequent users) — like cigarette smokers — can find it difficult to quit and can display withdrawal symptoms, as with drug addiction, when they don't smoke.

My advice: If parents have talked with their children and if teachers have told their kids about how smoking cigarettes is bad for them … kudos for that!  Now they have something else to talk about.

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