The Center for Tobacco Control Research and Education at UCSF is Not Sure Smoking is Any More Hazardous than Vaping

I recently read an article written by the director of the Center for Tobacco Control Research and Education at UCSF. What struck me most was the article's answer to the question "Is vaping safer than smoking?" The answer given was: "We don't know for sure."

OK, I realize that many years ago there was not a lot of research on the health effects of vaping and it had only been around for a short period of time, so perhaps we didn't know for sure that vaping was any safer than smoking. That was in 2008 - a full 16 years ago. Before criticizing the article, I thought I should check the date. Perhaps this was an old article that simply was not taken down from the web site and there was no reason to make a big deal out of this.

The Rest of the Story

It turns out that the article was published on December 18, 2024 -- three days ago!

So you're telling me that in late 2024, the tobacco control center at UCSF is still not sure that smoking is any more hazardous than vaping? 

Even the tobacco industry doesn't claim that smoking is no more hazardous than vaping. In fact, unlike UCSF's tobacco control center, the tobacco industry readily admits that smoking is far more hazardous to your health than vaping. 

There are numerous clinical studies demonstrating that vaping is much safer than smoking, both in terms of respiratory health and cancer risk. We know, for example, that switching from smoking to vaping results in a reduction in respiratory symptoms as well as measurable improvements in lung function. We also know that people who vape rather than smoke have substantially lower levels of carcinogen biomarkers. 

So in 2024, to claim that we don't know if smoking is any more hazardous than vaping is not only absurdly wrong, it is also terribly irresponsible. If a doctor were to tell her patient that there's really no difference between vaping and smoking as we're not sure that smoking is actually any more hazardous than vaping, that would represent medical malpractice in my opinion. Even Dr. Stanton Glantz - the prestigious founder of the tobacco control center at UCSF - has no hesitation in acknowledging that smoking is more hazardous than just vaping (not counting dual use here). I'm not going to go into the voluminous data demonstrating that vaping is much safer than smoking, as I actually did that about 15 years ago. And the evidence has only become stronger and stronger since then.

In my view, then, making a public claim in 2024 that smoking may be no more hazardous than vaping represents what I guess we should call public health malpractice.

There's More to the Story

If that were the only false claim made in the article, it would be enough. But it doesn't end there.

The article goes on to claim that: "popular vapes can easily have the nicotine content of three cartons or 600 cigarettes."

So let's examine this claim:

The highest concentration of nicotine in any e-liquid that I'm aware of that is typically used is 50 mg/mL. Typically, a cartridge contains 0.5mL or 1.0mL. To be conservative, let's use 1.0mL. Thus, the highest nicotine content in a vape cartridge is 50mg. 

OK, what about a cigarette? The average nicotine content of a cigarette is 12-15mg. Again being conservative, let's go with 12mg.

So a single vape cartridge has 50mg of nicotine and a single cigarette has 12mg of nicotine. This means that a vape cartridge has the nicotine content of about 4 cigarettes.

So the claim that a vape cart has the same nicotine content as 600 cigarettes is off by a factor of 150!

Now, let's give the writer of this article the benefit of the doubt and assume they meant to be comparing the nicotine yield of a vape cartridge with the nicotine yield of cigarettes. This is quite a benefit since the statement clearly says "nicotine content".

Nevertheless, the highest average measured yield of a Juul-like (pod-like) vape device, standardized across multiple studies, is 2.83mg per 15 puffs. Let's assume you can get 150 puffs out of a 1mL cartridge. So the nicotine yield of a vape cartridge, conservatively, is 28mg. A cigarette delivers approximately 1mg of nicotine. So even if we make the comparison based on nicotine yield, a single vape delivers the equivalent amount of nicotine as 28 cigarettes. Not 600. The estimate in this article is only off by a factor of 21!     

Finally, let's just make the assumption that the full 50mg of nicotine in a 50mg/mL cartridge is delivered. The nicotine delivery of a cigarette is approximately 1mg. So at the very highest, a vape cartridge could deliver the nicotine equivalent of 50 cigarettes. The claim of 600 cigarettes is still off by an order of magnitude!

There's Even More to the Story

If only it ended there. The article goes on to claim that: "Teens who vape are 3 to 5 times more likely to start smoking cigarettes than their peers."

I have already explained why this is not true. Briefly, in 2011, smoking prevalence among high school students was 15.7%, while the prevalence of vaping was just 1.4%. By 2022, the prevalence of vaping among high school students had skyrocketed up to 14.1%, yet smoking among high school students dropped to just 2.0%. And by 2024, smoking prevalence among high school students was only 1.7%.

These data definitively refute the contention that e-cigarettes are a gateway to smoking among youth and are completely inconsistent with the claim that e-cigarette use leads to a 3-5-fold increase in youth smoking initiation rates.

The reason why all of these false claims are important is because they could well deter many smokers from trying to quit smoking using e-cigarettes and therefore, block a major pathway by which millions of smokers have successfully quit smoking completely. The author of the article herself has published data showing that perceptions of the harms of e-cigarettes are related to decreased success in smoking cessation. 

I'm not concerned about the false claims in this article merely because they are providing misinformation. I'm concerned because they may actually cause population health harm by deterring smoking cessation. After all, if we don't know that smoking is any more hazardous than vaping, then what is the rationale for switching from smoking to vaping? There is abundant evidence that the mistaken belief that smoking may be as harmful as vaping is a strong deterrent to smoking cessation on a population level. Why is this something the tobacco control center at UCSF would want to contribute to?