Anti-tobacco group the Truth Initiative claims vaping contributes to depression in teenagers. Its argument is based on a shallow reading of the evidence.
As a new parent, I've rapidly discovered what a dangerous place the world is for children. It's an overwhelming realization at times. Given all the real threats my wife and I have to guard against, I can't understand why anyone would invent health scares that needlessly worry America's moms and dads, yet this seems to be the tobacco control movement's specialty. Earlier this week, for example, the Truth Initiative (TI) launched a campaign highlighting the alleged mental health risks associated with teen vaping as part of their broader effort to restrict access to electronic cigarettes (also called "e-cigarettes" or "vapes.")
“Two health crises among youth — a mental health crisis and a vaping epidemic — pose increasing threats to a generation of young people,” the Truth Initiative wrote in a report accompanying its new marketing campaign. “While it is well known that nicotine harms developing brains … lesser known are the worrying connections between nicotine and mental health.”
Activist-group rhetoric aside, no evidence implicates vaping in teenage depression. There is an established link between the disease and nicotine consumption, though it's a complicated relationship that doesn't lend itself to political causes.
A causal relationship?
Our first clue that the Truth Initiative is wandering away from the data comes from—the Truth Initiative. The executive summary of its new report included this important qualifier:
Though it is unknown whether a causal relationship between nicotine and mental health conditions exists, there are troubling links between vaping nicotine and worsening symptoms of depression and anxiety, as well as higher odds of having a depression diagnosis among those who use nicotine [my emphasis].
This statement tells us right off the bat that the nicotine-mental health connection is messy. There could be many other factors that influence the association in various ways. After surveying the evidence, it's my contention that TI's analysis is backwards: the stimulant doesn't cause or amplify feelings of depression; people suffering from the condition seek relief in nicotine consumption. According to a 2017 review of almost 300 studies:
... [A]dverse internal states are the primary drivers of smoking behavior in depressed individuals. Accordingly, experimental treatment approaches which seek to modify reactivity to external smoking cues (e.g., via cognitive bias modification) are unlikely to be effective in depressed smokers [my emphasis].
Rather, treatments should identify the adverse motivational states that are the primary drivers of smoking in each individual and personalize treatment to target those states. Further, effective intervention strategies should address smokers’ beliefs about the high reward value of smoking in these motivational states.
This is a significant challenge to TI's thesis. Their activism is built on the assumption that removing “external smoking cues,” restricting e-cigarette marketing to adults for example, is the best way to discourage vaping, which is clearly not the case for depressed patients. That said, it is always unethical to market nicotine products to children, and ACSH opposes minors having access to any nicotine-containing products.
Why are depression and smoking linked?
“Why?” is a difficult question to answer in this case, but one possibility that adds some clarity is that nicotine has a well-documented antidepressant effect. Because it stimulates dopamine release, depressed patients often resort to smoking (or vaping) to mitigate the “adverse effects of stressful stimuli.” Depressed smokers have reported mood improvements that depression-free smokers don't experience after finishing a cigarette.
Several studies have also produced the same antidepressant effect in rodents, while other experiments have shown that nicotine can enhance the beneficial effects of some antidepressant drugs. The Truth Initiative seems to be aware that mental illness often leads to nicotine use as patients seek symptom relief, pointing out that its “surveys reveal that many young people cite feelings of stress, anxiety, or depression as reasons they start and continue vaping.”
TI tried to argue around this by pointing to nicotine-withdrawal symptoms, which can mirror the effects of depression. "The common misconception that nicotine relieves stress, anxiety, and depression, may be rooted in the cycle of nicotine withdrawal," the group's report states. But that's a different phenomenon than causing or amplifying a patient's depression.
Crucially, there is some evidence that vaping actually reduces nicotine dependence by minimizing the peaks and troughs in blood nicotine smokers experience. If that's the case, vaping may help mitigate the withdrawal symptoms commonly associated with smoking cessation.
Of course, if vaping contributes to depression, then so do any smoking-cessation treatments that contain nicotine, which would include FDA-approved patches and gums endorsed by anti-tobacco groups. More importantly, the majority of teenagers do not vape. The few who do are already smokers in most cases. It follows, then, that regulations restricting adult access to vapor products will not help reduce nicotine use among teens.
A complicated disease, oversimplified
Chronic nicotine consumption may alter brain receptors that can lead to depression, but that's not terribly useful as an argument against vaping. We still need to know why now-depressed individuals seek out vaping in the first place. Do they have a genetic predisposition for nicotine dependence and depression? Did they develop a habit of smoking when drinking socially, which led to nicotine addiction? These are just some of the possibilities researchers are investigating.
The bigger issue is that depression, like many other diseases, probably has multiple causes that can augment each other. “Your genetic makeup influences how sensitive you are to stressful life events,” Harvard Medical School notes. “When genetics, biology, and stressful life situations come together, depression can result.” How these various factors contribute to the disease varies from one patient to the next, and there's still a lot we don't know.
What we do know is that, while researchers are investigating the depressive effects of childhood sexual abuse and the loss of a parent early in life, the Truth Initiative is running slickly produced videos referring to vapes as “depression sticks” and staging videos where a fake vaping company executive tries to “honestly” market his product to convenience stores. “Nicotine can amplify depression and anxiety,” he tells the cashier, “so I'm trying to sell some depression!”
Is that the work of a group truly concerned about mental illness? Color me skeptical.