First, as a disclaimer, I would like to state that ANY kind of smoke inhalation is damaging to the lungs because of direct irritation from the smoke. E-cigarettes are also problematic in that they contain nicotine, the addictive substance in cigarettes, and there are concerns that never-smokers are using them under the assumption that they are “safe” and being exposed to toxins in e-cigarettes.
So, what are the contents of an e-cigarette?
There is a large market in the US ($2 billion/year industry). Between 20-50% of current smokers report having tried e-cigarettes at some point–that’s 6% of the total US population.
There are many reasons why someone might try an e-cigarette. It can prevent nicotine withdrawal symptoms, alleviate the psychosocial anxiety of being the only person in a group to not smoke, and sneak around non-smoking regulations. (Sometimes–there are still heated debates about whether or not vaping should be included under non-smoking laws.) Furthermore, advertising has convinced over 75% of current smokers that e-cigarettes are safer than real cigarettes. The vapors of the “e-juice” also come in flavors ranging from chocolate to fruity. Yum–maybe?
Aside: many major US tobacco companies are investing in or buying up e-cigarette makers and supporting pro-vaping ad campaigns and lobbying. Does anyone see a conflict of interest here?
Part of the problem with assessing the health risks of e-cigarettes is that there are so many different kinds! There are now four generations of e-cigarettes, each fancier and sleeker than the last. Also, they’re just too new for us to know if there are long-term health effects–the longest study was 24 months of follow up.
Regardless, we do know that some of the ingredients are definitely cytotoxic and carcinogenic. Cinnamaldehyde (found in cinnamon-flavored e-juice), as well as diethylene glycol, found in antifreeze, as well as formaldehyde, have been found in FDA testing.
Events reported to the FDA have ranged from minor–mouth dryness, irritability, nausea–to major–tachycardia and seizure, pneumonitis, and burns from exploding cigarettes and nicotine poisoning especially among children.
Are e-cigarettes useful for smoking cessation? Fun fact: they are not FDA approved for this indication! This Mayo Clinic review reports that there have only been two large studies with e-cigarettes showing that there was not an impressive difference between e-cigarettes and nicotine patches/other traditional methods, and that differences had vanished by 6-12 months. They specifically say, “For the practicing clinician, the American Heart Association suggests that clinicians should not recommend e-cigarettes as primary cessation aids, and if a patient is using e-cigarettes, he/she should be advised to consider a quit date for using them and not plan to use them indefinitely.”
In this expansive review from the Journal of American Medicine, the variability in evidence shows that most likely, e-cigarettes do NOT promote smoking cessation and may in fact promote continued intermittent tobacco use. While “real-world” surveys show dramatic results, studies have shown that smokers who use e-cigarettes are more likely to continue smoking compared to nonusers, are more nicotine dependent, and was negatively associated with the desire to quit.
The Mayo clinic review concludes:
1. They are not demonstrably superior to FDA-approved medications for smoking cessation.
2. They may not be effective for smoking cessation and dual use (ie, using e-cigarettes and continuing to smoke) will prolong exposure to tobacco.
3. They are not FDA-approved for the treatment of tobacco dependence.
4. Short-term safety data suggest they may cause airway reactivity.
5. The long-term health risk of exposure to e-cigarette constituent chemicals is unknown.
6. No regulatory oversight, such as requirements for good manufacturing practices, is currently in place for e-cigarette devices or e-juice.
The bottom line is that right now, it looks like e-cigarettes may help cut down on the amount of tobacco cigarettes that are smoked. But this is NOT a clinically significant metric because we know that there is a non-linear relationship between # of cigarettes smoked and health risk, and that NO safe tobacco smoking level is safe.
If you’re interested in the evidence, see this review of the safety profile of e-cigarettes. Hopefully, there will be more evidence that comes along.