Based on evidence that chemicals often found in e-cigarette aerosol produce endothelial dysfunction and decreased arterial compliance, Dr. Aruni Bhatnagar of the University of Louisville has concluded that e-cigarettes are no safer than real cigarettes, and Dr. Stan Glantz has argued that vaping is up to half as dangerous as smoking. Both of these anti-vaping researchers reasoned that since the dose-response relationship between smoking and cardiovascular disease is non-linear and risk saturates at rather low levels of exposure, and since e-cigarettes contain chemicals that can cause acute cardiovascular injury, vaping is therefore not much safer than (Glantz) or no safer than (Bhatnagar) smoking.
Bhatnagar concludes that: "The dose-response relationship between smoking and cardiovascular
mortality is non-linear, suggesting that reduction in HPHC
concentrations in e-cigarette aerosols may not result in proportional
harm reduction and decreased HPHC exposure may be offset by increased
use by individuals who believe that e-cigarettes are safer than
conventional cigarettes. Thus, taken together, current evidence does not
entirely support the notion that e-cigarettes are reduced harm products... ."
Glantz concludes that: "Given the evidence that effects on the cardiovascular system and lungs
account for more than half the smoking-induced deaths and that at least
some of the short-term effects of e-cigarette use on these systems are
comparable to cigarettes, agencies concerned about public health should
consider them at least 1/3 as bad as cigarettes and maybe as high as half as bad (or higher)."
The Rest of the Story
A study published in the Journal of the American College of Cardiology
found that the hyperglycemic state associated with eating Corn Flakes
results in measurable decrements in endothelial dysfunction, as assessed
by endothelium-dependent flow-mediated dilation, among obese and
overweight non-diabetic adults (see: Lavi T, et al. The acute effect of
various glycemic index dietary carbohydrates on endothelial function in
nondiabetic overweight and obese subjects. Journal of the American College of Cardiology 2009; 53:2283-2287).
The
study found that: "Baseline FMD [flow-mediated dilation], not significantly different in the 3
carbohydrate-based meals, was reduced 2 h post-prandially in all groups,
showing statistical significance in only high-glycemic index meals:
glucose (15 ± 9% vs. 10 ± 8%, p < 0.01), cornflakes (13 ± 7% vs. 9 ±
7%, p < 0.01)."
Cigarette smoking has been shown to have similar effects on the endothelium.
So based on the above reasoning:
Given the evidence that effects on the cardiovascular system and lungs
account for more than half the smoking-induced deaths and that at least
some of the short-term effects of Corn Flakes ingestion on these systems are
comparable to cigarettes, agencies concerned about public health should
consider them at least 1/3 as bad as cigarettes and maybe as high as half as bad (or higher).
Using this reasoning, the cigarette companies would be justified in taking out advertisements that say: "Smoking is only twice as bad as eating Corn Flakes."
Bhatnagar and Glantz are making wild extrapolations that are simply not justified based on the nature of the existing data. And Bhatnagar's paper admits as such:
"CVD [cardiovascular disease] is a result of pathological changes in several processes (blood pressure regulation, cholesterol metabolism, insulin signaling, and endothelial function), and, therefore, the cardiovascular effects of inhaled toxins cannot be adequately simulated by simple in vitro assays but must be studied in animal models and humans... . Unfortunately, such data are not available for e-cigarettes... ."
So if the data needed to understand the effects of e-cigarettes on cardiovascular risk are not available, how are these researchers able to quantify the cardiovascular risk associated with vaping and to conclude that vaping is half as harmful or equally harmful to smoking?
The answer appears to be that they have drawn a pre-determined conclusion and are simply manipulating the existing data to support these conclusions.
If a cigarette company were to take out an ad saying: "Cigarette smoking is only half as bad as vaping," it would be attacked for making fraudulent statements and undermining the public's appreciation of the severe hazards of smoking. But the truth is that Altria could take out an ad today which truthfully informed smokers that: "Tobacco researchers have concluded that smoking is no more hazardous than, or only twice as hazardous as vaping. So if you're thinking of quitting smoking using e-cigarettes to improve your health, don't bother."
Sadly, this is precisely the message that these anti-vaping researchers are sending to smokers throughout the world. Don't quit because your Marlboros, Camels, and Newports are little worse than using tobacco-free e-cigarettes. And if you already have quit by switching to vaping, you might as well go back to smoking. These are dangerous statements that clearly undermine the public's appreciation of the hazards of smoking and which do actual public health damage by deterring many smokers from quitting and encouraging many ex-smokers to return to smoking.
I'm surprised that Altria doesn't take out ads saying: "Marlboro: 100 times the pleasure of an e-cigarette, but with only half the risk." Or that Reynolds American doesn't take out an ad saying: "Camel cigarettes: The same level of safety that you expect with a tobacco-free e-cigarette, but 100 times the pleasure."
Meanwhile, while anti-vaping researchers like Glantz and Bhatnagar are busy making wild extrapolations, some researchers are actually conducting clinical studies that measure the demonstrated effects of smoking compared to vaping in humans. And these studies are showing that vaping dramatically reduces health risks. Multiple studies, for example, have documented that asthmatic smokers who switch to vaping experience an improvement in their respiratory symptoms as well as in their lung function, as measured by spirometry.
And just today, a new study published in the journal Toxicology Mechanisms and Methods reports that smokers who quit by switching to electronic cigarettes experience a reduction in exposure to harmful and potentially harmful constituents which is equivalent to that experienced by smokers who quit completely (without the use of e-cigarettes).
Specifically, exposure to chemicals such as tobacco-specific nitrosamines and volatile organic compounds including acrolein, benzene, and acrylonitrile was reduced by the same amount among smokers who quit using e-cigarettes and those who quit without e-cigarettes. Furthermore, blood levels of carboxyhemoglobin were reduced by the identical amount in smokers who quit using vs. not using e-cigarettes.
The study was funded by Fontem Ventures, which is a subsidiary of Imperial Brands (a tobacco company which is also marketing e-cigarettes). While this needs to be considered in evaluating the validity of the findings, I do not see any scientific issues in the methodology or reporting of the results that lead me to question the validity of the basic finding that biomarkers of exposure to the above chemicals decreased by the same amount in smokers who switched to vaping as in smokers who quit completely without the aid of e-cigarettes.
That Glantz and Bhatnagar do not even mention these studies demonstrates an apparent bias. Strangely, there are extrapolating from data that does not directly measure e-cigarette risks among humans and ignoring data that directly measures the effects of e-cigarettes in the clinical setting.
To be clear, I am not arguing that vaping is risk-free or that exposure to chemicals such as formaldehyde and acrolein is not a problem. In fact, I have advocated directly addressing these risks by forcing the FDA to set standards for these chemicals, either directly or by regulating maximum coil temperatures or voltage/resistance combinations. This is an approach that, ironically, anti-tobacco groups have not supported. Instead, they want to virtually wipe out the vaping industry, which would likely cause tens of thousands of ex-smokers to return to cigarette smoking.
It should also be noted that both Glantz and Bhatnagar are claiming that vaping causes chronic obstructive lung disease. This claim is based solely on evidence of acute irritation of the airways associated with vaping. But it ignores research showing that vaping has no effect on clinical lung function, as measured by spirometry (which is in sharp contrast with cigarette smoking). It also ignores research showing that smokers who switch to vaping experience dramatic improvement in their lung function. To be clear to readers, there simply is not any existing evidence that vaping causes chronic obstructive lung disease. But this is precisely the assumption that goes into Dr. Glantz's estimate that vaping is half as harmful as smoking.
The information that we tell the public regarding the relative safety of smoking vs. vaping is critical and it truly has life or death implications. The public is relying on this information to make important decisions such as whether to try to quit smoking with e-cigarettes or to stay on tobacco cigarettes, or whether to continue vaping or to return to smoking. The statements of anti-vaping researchers like Glantz and Bhatnagar are instructing smokers not to try to quit smoking with e-cigarettes and are undoubtedly causing many former smokers to return to smoking.
The tragedy, and the rest of the story, is that these recommendations are based on extremely weak science, involve wild and unsupportable extrapolations, ignore actual clinical studies of the effects of vaping vs. smoking, and show evidence of severe bias.
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