Tobacco and Marijuana
This information was prepared by the National Cannabis Prevention and Information Centre in Australia, and used with permission. Some information may not be accurate for U.S. readers.
There are many studies that report on the harmful health effects of smoking tobacco, such as cancer, respiratory disease (bronchitis, emphysema and asthma) and heart disease. While there have been few studies conducted on the effects of marijuana smoke, there is growing evidence that there are similar major health concerns for those who smoke marijuana.
Tobacco and marijuana smoke both contain harmful chemicals which are absorbed when inhaled. This exposes the smoker’s lungs to greater risks of developing major respiratory diseases and/ or cancer. The cannabis plant does not contain nicotine, however if cigarettes are combined with marijuana ("mulling') then nicotine will be absorbed along with the marijuana smoke.(1)
What are the links between smoking tobacco and marijuana?
International reports have found specific links between smoking both tobacco and marijuana, such as:
- Many people who try marijuana have previously smoked tobacco.
- Many current marijuana smokers are also current cigarette smokers.
- Early onset of tobacco use may act as a "gateway" to future marijuana use.
- Nicotine dependence can develop if tobacco is used in combination with marijuana.
- Smoking both marijuana and tobacco increases health risks rather than smoking each alone.
Are there any differences in smoking marijuana versus tobacco?
Tobacco is usually smoked in commercially made or sometimes ‘roll your own’ cigarettes, while marijuana is smoked in a variety of ways, such as:
- A pipe with/without tobacco;
- A joint "roll your own" cigarette with a long cardboard tip, with/without tobacco;
- A bong (water pipe) or bucket bong with/without tobacco.
The most harmful way of smoking marijuana is through a bong. Inhaling smoke through water makes it cooler, which makes it easier for the smoker to inhale a greater volume of smoke more deeply into the lungs. This increases the surface area for tar and other carcinogens to affect the respiratory system.
Mixing tobacco with marijuana is polydrug use. Nicotine is an addictive drug and the combination of these two substances increases exposure to tar and other carcinogens, causing greater risks to the lungs, respiratory organs as well as the cardiovascular system.
Marijuana smokers are also at risk of developing nicotine dependence if they mix tobacco with their marijuana.
Compared to tobacco cigarette smokers, people who smoke marijuana typically:
- Inhale more smoke (two-thirds larger puff volume);
- Inhale the smoke deeper into the lungs (one-third greater depth of inhalation);
- Hold the smoke in the lungs for longer time periods (up to four times longer).
This results in the lungs being exposed to:
- Greater amounts of carbon monoxide and other smoke irritants;
- Greater retention of tar in the respiratory tract.
Both carbon monoxide and tar increase the risks of a range of health problems including respiratory tract infections, bronchitis and lung cancer.
(1) Bélanger RE, Akre C, Kuntsche E, Gmel G, Suris JC. Adding tobacco to cannabis--its frequency and likely implications. Nicotine Tob Res 2011;13(8):746-50. doi: 10.1093/ntr/ntr043.
This information adapted with permission from the National Cannabis Prevention and Information Centre in Australia.