Water pipe smoking, also called hookah, shisha, or narghile, delivers many of the same toxicants found in cigarette smoke and adds a few of its own. A single hookah session typically lasts 30 to 60 minutes or longer, during which a smoker may inhale far more smoke volume than they would from a cigarette. Despite widespread belief that the water in the device filters out harmful substances, research consistently shows it does not, and the practice carries real risks for the lungs, heart, gums, and developing fetuses. The story is more nuanced than “hookah equals cigarettes,” though, because the charcoal, the flavorings, and the social setting all create a distinct risk profile worth understanding on its own terms.
The Water Filtration Myth
The single most persistent misconception about water pipe smoking is that the water acts as a filter, scrubbing out nicotine, tar, and cancer-causing chemicals before they reach your lungs. Surveys consistently find that a majority of hookah users believe the practice is less harmful than cigarettes, and the water-filtration idea is the main reason why.1PubMed Central. Perceptions of hookah smoking harmfulness: predictors and characteristics among current hookah users One study of college students found that roughly 27% believed hookah did not even contain tobacco, and 38% thought it was nicotine-free.2PubMed Central. College students’ perceptions and knowledge of hookah use
In reality, the water cools the smoke but does not meaningfully filter nicotine, tar, or carcinogens. And that cooling effect is part of the problem: because the smoke feels less harsh, smokers tend to inhale more deeply and hold the smoke longer, driving particles further into the lungs.3PubMed Central. Waterpipe smoking: not necessarily less hazardous than cigarette smoking The sensation of smoothness is not a sign that something dangerous has been removed. It is a sign that you are able to pull in a much larger volume of smoke per breath than you would tolerate from a cigarette.
Where the Toxicants Actually Come From
Hookah smoke is not just heated tobacco. It is a mixture of combustion products from two sources: the flavored tobacco (called mu’assel or shisha) and the charcoal briquette placed on top to provide heat. Research measuring the chemical output of a typical hookah session found that roughly 90% of the carbon monoxide and 75 to 92% of the cancer-linked polycyclic aromatic hydrocarbons (PAHs) in the smoke came from the charcoal, not the tobacco.4PubMed. Charcoal emissions as a source of CO and carcinogenic PAH in mainstream narghile waterpipe smoke More than 95% of benzo(a)pyrene, one of the most potent carcinogens in tobacco smoke, was attributable to the charcoal alone.
The charcoal itself also varies. Testing of different charcoal products sold in stores and cafés found that the amount of PAH residue in raw charcoal varied by a factor of six from the cleanest to the dirtiest product, and those residues accounted for more than half of the total PAHs in the combined mainstream and sidestream smoke.5PubMed Central. Carcinogenic PAH in waterpipe charcoal products This means that two hookah sessions using the same tobacco but different charcoal brands can deliver substantially different carcinogen loads. It also means that eliminating charcoal, for instance by using an electric heater, would cut the single largest source of carbon monoxide and PAHs from the smoke.6PubMed. Comparison of CO, PAH, Nicotine, and Aldehyde Emissions in Waterpipe Tobacco Smoke Generated Using Electrical and Charcoal Heating Methods
On top of the charcoal contribution, a systematic review cataloged hookah smoke as containing at least seven known carcinogens, 39 central nervous system depressants, and 31 respiratory irritants.7PubMed. Epidemiology and Adverse Consequences of Hookah/Waterpipe Use: A Systematic Review So even without the charcoal, the tobacco portion of the smoke is far from clean.
What Flavorings and “Herbal” Products Add
Flavored tobacco is central to hookah’s appeal, and hookah lounges market the variety of flavor options as a primary draw for customers.8PubMed Central. How Do Waterpipe Smoking Establishments Attract Smokers? Implications for Policy But the flavoring compounds themselves are not inert once heated. Laboratory testing of common flavorants like cinnamaldehyde and menthol showed that at higher temperatures, they break down into formaldehyde, acetaldehyde, and benzene, all recognized harmful or potentially harmful constituents of tobacco smoke.9PubMed Central. Composition of aerosols from thermal degradation of flavors used in ENDS and tobacco products Superheating flavored hookah tobacco at high temperatures released 81 new volatile compounds not present in the unheated product, most originating from coal tar degradation rather than the flavor itself.10Scientific Reports. The characterization of flavored hookahs aroma profile and in response to heating as analyzed via headspace solid-phase microextraction (SPME) and chemometrics
Some smokers assume that “herbal” or tobacco-free hookah products are a safe alternative. Testing of these products tells a different story. One analysis found that the toxic byproducts produced by the combustion of herbal shisha were equivalent to or greater than those from tobacco shisha. The herbal products also showed considerable variation in heavy metals like lead, chromium, nickel, and arsenic.11Tobacco Control. ‘Herbal’ but potentially hazardous: an analysis of the constituents and smoke emissions of tobacco-free waterpipe products and the air quality in the cafés where they are served The charcoal still burns, the smoke still forms, and much of what makes hookah smoke harmful has nothing to do with whether tobacco is in the bowl.
Nicotine Exposure and Addiction Potential
Hookah delivers meaningful amounts of nicotine, enough to sustain dependence in regular users. After a social hookah session, urinary cotinine (a breakdown product of nicotine that researchers use to gauge exposure) increased about 8.5 times among hookah smokers. Occasional smokers showed the steepest spike, with cotinine levels jumping about 31 times above their baseline.12PubMed Central. Levels of Urine Cotinine from Hookah Smoking and Exposure to Hookah Tobacco Secondhand Smoke in Hookah Lounges and Homes That last figure is striking because it suggests that people who smoke hookah infrequently are not getting “less nicotine” in a meaningful sense; their bodies just have less tolerance for it.
National data from the United States tell a similar story. Among past-30-day hookah users in the PATH study, urinary cotinine levels were about 10.6 times those of people who had never used any tobacco product. The same hookah users also showed elevated biomarkers for a tobacco-specific carcinogen (NNAL, a metabolite linked to lung cancer risk), PAHs, and several volatile organic compounds including acrylonitrile and acrolein.13International Journal of Environmental Research and Public Health. Biomarkers of exposure among USA adult hookah users: Results from Wave 1 of the Population Assessment of Tobacco and Health (PATH) Study (2013-2014) The biomarker picture makes clear that hookah is not a low-exposure activity, even for people who only smoke a few times a month.
Carbon Monoxide Poisoning as an Acute Risk
One danger that is almost unique to hookah among tobacco products is acute carbon monoxide poisoning. Because the charcoal generates large amounts of CO and a typical session lasts well over half an hour, blood levels of carboxyhemoglobin (the form of hemoglobin bound to CO instead of oxygen) can climb high enough to cause poisoning symptoms during or shortly after a session. In a case series, symptomatic patients who had been smoking hookah showed carboxyhemoglobin levels ranging from about 20% to 30%, well into the danger zone for headaches, dizziness, nausea, and impaired judgment.14PubMed Central. Carbon monoxide poisoning following use of a water pipe/hookah For context, non-smokers typically have carboxyhemoglobin levels below 3%.
Emergency physicians have flagged that CO poisoning should be considered in any patient arriving with vague symptoms after hookah use. And smoking outdoors does not eliminate the risk; at least one documented case of CO toxicity occurred in a non-enclosed environment.15PubMed Central. Tobacco hookah smoking-induced carbon monoxide poisoning: A case report of non-ambient exposure The combination of high CO output from charcoal and prolonged inhalation makes this a real and underappreciated emergency risk.
Heart and Blood Vessel Effects
The cardiovascular evidence is building, and the picture is not reassuring. In a community-based study, exclusive water pipe smokers showed higher arterial stiffness and wave reflection compared to non-smokers, with the increase tracking in a dose-dependent way: more hookah use meant stiffer arteries.16PubMed. The association of waterpipe smoking with arterial stiffness and wave reflection in a community-based sample Arterial stiffness is a well-established predictor of heart attack and stroke, so these findings are clinically relevant even though they are based on a measured marker rather than a tally of cardiac events.
Even a single session appears to matter. A study in young adults aged 18 to 34 found that one hookah session increased aortic stiffness by a magnitude comparable to what has been reported for a single cigarette. The authors noted that this directly challenges the marketing message that hookah is a safer alternative.17PubMed. Acute Effect of Hookah Smoking on Arterial Stiffness and Wave Reflections in Adults Aged 18 to 34 Years of Age The acute cardiovascular hit, in other words, is not discounted by the fact that hookah is used intermittently by most of its users.
Lungs and Cancer
Chronic obstructive pulmonary disease (COPD), the umbrella term for emphysema and chronic bronchitis, is a confirmed risk for hookah smokers. In one study of hookah users, about 10% met diagnostic criteria for COPD, with rates climbing among those who smoked three or more hookahs per day and those who had been smoking for many years.18PubMed Central. The prevalence of chronic obstructive pulmonary disease in hookah smokers Duration of smoking and daily frequency were independent predictors of the disease, meaning that long-term, heavy hookah use damages the airways in much the way cigarettes do.
On the cancer front, a systematic review concluded that there is sufficient evidence to link water pipe smoking with cancer, with the strongest association for lung cancer.19PubMed Central. Assessing the Effect of Waterpipe Smoking on Cancer Outcome – a Systematic Review of Current Evidence A case-control study in Kashmir found that hookah smoking nearly doubled the odds of esophageal squamous cell carcinoma, with the association holding across different measures of intensity, duration, and cumulative use.20PubMed Central. Hookah smoking, nass chewing, and oesophageal squamous cell carcinoma in Kashmir, India The esophagus finding makes anatomical sense: hookah smoke passes directly through the mouth and throat, bathing those tissues in carcinogens.
Damage to Gums and Teeth
Periodontal disease, meaning gum disease that can eventually cause tooth loss, appears to be at least as common in hookah smokers as in cigarette smokers. In a Saudi population study, the prevalence of periodontal disease was 30% among water pipe smokers, compared to 24% in cigarette smokers and 8% in non-smokers. The relative risk of periodontal disease was about five times higher for water pipe smokers than for non-smokers, and about four times higher for cigarette smokers, suggesting that hookah may actually be somewhat worse for gum health than cigarettes.21PubMed. Tobacco smoking and periodontal health in a Saudi Arabian population
A study among dental students in Sarajevo confirmed that hookah users showed worse periodontal health than non-smokers, even when those users maintained good oral hygiene. The researchers emphasized that hookah should not be considered a healthier alternative for the mouth any more than for the rest of the body.22PubMed Central. The Effects of Smoking “The Hookah” on the Oral Health of Fourth, Fifth and Sixth-year Students of the Faculty of Dentistry in Sarajevo
Pregnancy and Newborn Health
Water pipe smoking during pregnancy is associated with lower birth weight, and the effect may be as large as or larger than the effect of cigarettes. One retrospective study found that babies born to waterpipe-only smokers weighed an average of about 0.47 kg less than those born to non-smokers. Cigarette-only smokers’ babies averaged about 0.23 kg less. Dual users fared worst, at roughly 0.59 kg below non-smokers. Similar patterns appeared for newborn length and head circumference, with hookah-exposed babies showing reductions in both.23PubMed. Anthropometric measurements of newborns of women who smoke waterpipe during pregnancy: a comparative retrospective design
A study of pregnant women in Cairo confirmed higher exhaled CO levels in smokers and found that smokers had greater odds of premature birth and low birth weight babies compared to non-smokers, with dual cigarette-hookah smokers at the highest risk.24PubMed Central. Exclusive and Dual Cigarette and Hookah Smoking Is Associated with Adverse Perinatal Outcomes among Pregnant Women in Cairo, Egypt The persistent idea that hookah is “mild enough” for pregnancy is flatly contradicted by the data.
Secondhand Smoke in Hookah Lounges
If you do not smoke hookah yourself but spend time in a hookah bar, you are still being exposed. Air quality measurements in hookah lounges have found particulate matter concentrations ranging from “unhealthy” to “hazardous” by EPA standards, posing risks not only to patrons but especially to employees who breathe that air for entire shifts.25PubMed Central. Measuring Indoor Air Quality of Hookah Lounges In New York City hookah bars, average fine particulate matter was extremely high, and airborne nicotine was detected in every bar tested.26PubMed Central. Air Quality in New York City Hookah Bars
For employees, the situation is particularly concerning. Measurements of air quality during hookah bar work shifts found high levels of fine particulates and black carbon, with CO levels peaking above 20 ppm in at least one venue.27PubMed. Secondhand hookah smoke: an occupational hazard for hookah bar employees Non-smokers who attended a hookah social event had their cotinine levels increase about 2.5 times just from being in the room, confirming that secondhand hookah smoke delivers measurable nicotine exposure even to bystanders.28PubMed Central. Levels of Urine Cotinine from Hookah Smoking and Exposure to Hookah Tobacco Secondhand Smoke in Hookah Lounges and Homes
Sharing the Mouthpiece and Infectious Disease
Hookah is inherently social, and sharing the pipe is part of the ritual in many cultures. That shared mouthpiece creates a transmission route for respiratory and oral infections. Case reports and microbiological studies have identified bacteria, fungi, and viruses on hookah components, including organisms associated with tuberculosis, staph infections, and oral herpes.29International Journal of Medical Science and Dental Health. Isolation and Diagnosis or Identified Microorganisms for Hookah in Najaf Province Water pipe smoking has been specifically flagged as a risk factor for transmitting tuberculosis, with documented cases involving shared pipes.30PubMed Central. Water-pipe Smoking as a Risk Factor for Transmitting Mycobacterium tuberculosis
Disposable plastic mouthpieces are widely offered in hookah lounges and are sometimes assumed to solve this problem. They reduce direct lip-to-lip contact with the shared hose, but the water basin, the hose interior, and the pipe body remain shared, so the protection is incomplete. In communities where tuberculosis or other respiratory infections are endemic, hookah sharing adds a meaningful public health concern on top of the chemical risks.31PubMed Central. Prevalence, knowledge and practices of shisha smoking among youth in Kampala City, Uganda
Poly-Tobacco Use and the Gateway Question
Hookah rarely exists in a vacuum. Among young adult non-daily smokers, about a third reported hookah use in the past two weeks, and more than a third of those who used hookah or e-cigarettes reported using both products.32PubMed Central. Expectancies for and Use of E-Cigarettes and Hookah among Young Adult Non-Daily Smokers In a study of university students who smoked water pipe across Egypt, Jordan, and Palestine, about 45% also used at least one other tobacco product, most commonly cigarettes.33PubMed. Poly-Tobacco Use among Young Adult Waterpipe Smokers: Insights from University Students in Three Eastern Mediterranean Countries Adolescents in Kuwait showed similar layering of products, with nearly 13% reporting concurrent use of e-cigarettes, conventional cigarettes, and hookah.34Tobacco Induced Diseases. Patterns of electronic cigarette, conventional cigarette, and hookah use and related passive exposure among adolescents in Kuwait: A cross-sectional study
This overlap complicates efforts to study hookah’s health effects in isolation, because many real-world hookah smokers are simultaneously exposed to other tobacco products. It also means that assessing someone’s total nicotine and carcinogen load requires asking about all the products they use, not just one.
Quitting Hookah
The evidence base for hookah-specific cessation programs is thin compared to the mountain of research behind cigarette cessation, but the few trials that exist are encouraging. A Cochrane review found that behavioral interventions, both brief and intensive, increased waterpipe smoking abstinence compared to control groups. One trial showed that behavioral counseling roughly doubled quit rates at six months, and adding bupropion (a medication commonly used for cigarette cessation) raised the effect slightly further.35Cochrane Database of Systematic Reviews. Interventions for waterpipe smoking cessation
A pilot randomized trial found that even a brief behavioral intervention produced prolonged abstinence in about 30% of participants at three months, rising to about 44% with a more intensive version.36PubMed Central. Behavioral cessation treatment of waterpipe smoking: The first pilot randomized controlled trial That said, the effect sizes for hookah cessation interventions appear smaller than those for the same interventions applied to cigarette smokers.37Nicotine & Tobacco Research. Effect of Cessation Interventions on Hookah Smoking: Post-Hoc Analysis of a Cluster-Randomized Controlled Trial Why this gap exists is not entirely clear, but it could reflect the social nature of hookah use: quitting a solitary habit is one thing, while quitting a group activity tied to cafés, friends, and cultural tradition is another.
Regulation and the Industry Landscape
Hookah tobacco occupies a regulatory gray zone in many countries. In the United States, proposed policy interventions include equalizing tobacco tax rates across product types (hookah tobacco is often taxed at a lower rate than cigarettes), requiring accurate warning labels on hookah products, extending the ban on characterizing flavors to hookah tobacco, and removing clean-indoor-air exemptions that some jurisdictions grant to hookah lounges.38PubMed Central. Opportunities for policy interventions to reduce youth hookah smoking in the United States Researchers have also called for health warnings to be placed not only on tobacco packs but also on the hookah apparatus itself and inside hookah-serving premises, since many smokers never handle the tobacco packaging.39PubMed Central. Impact of Waterpipe Tobacco Pack Health Warnings on Waterpipe Smoking Attitudes: A Qualitative Analysis among Regular Users in London
The industry itself is global and growing. Tobacco is produced largely in countries like Egypt and India, while hookah devices are often manufactured in China due to lower production costs, with a small segment of high-end glass pipes made in Eastern Europe. Industry insiders have noted that the European market may be approaching saturation, and manufacturers are now targeting previously unexplored regions like New Zealand, Russia, and Mexico, with new pricing strategies aimed at younger adults with less disposable income.40PubMed Central. Features of the waterpipe tobacco industry: A qualitative study of the third International Hookah Fair That trajectory, expanding into new youth markets with lower-cost products, mirrors the playbook of the cigarette industry decades earlier and gives public health researchers legitimate cause for concern.