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Vaping and Smoking Myths with Dr Judith Prochaska

07/07/21 Judith J. Prochaska, PhD, MPH, Stanford Prevention Research Center, Stanford University;

Season 3 | Episode 5


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>> News: Researchers are working hard to determine the cause of more than 500 cases of lung illness affecting e-cigarette users, 8 of those people have died. But even before this outbreak, e-cigarettes had divided the medical community. The American Lung Association says bluntly, “E-cigarettes are not safe.” But the American Cancer Society on the other hand says they are quote “significantly less harmful for adults than smoking regular cigarettes.” Another complication, the latest figures show nearly 5 million children use e-cigarettes.

>> Joe McIntyre: Hello! And welcome to another season of the Merck Manuals Medical Myths Podcast. I’m your host, Joe McIntyre and with me today, I have Doctor Judith Prochaska. Doctor Prochaska is a professor in the Department of Medicine at Stanford University, with the Standford Prevention Research Center and a member of the Standford Cancer Institute. Doctor Prochaska is a licensed clinical psychologist as well with a focus in addiction medicine. Doctor Prochaska, thank you for being here.

>> Dr. Prochaska: Thank you for having me, Joe.

>> Joe McIntyre: So, we have Doctor Prochaska on to talk about a topic that has been discussed widely in the news and also at schools, quite frankly across the U.S. This topic of vaping and specifically childhood vaping vs smoking and how those two topics differ and how in many instances, they’re similar. So, Doctor Prochaska I’m going to start with a seemingly easy question, but I’m sure that has a complicated answer. Is vaping just as bad for your health as smoking is? Is it healthier, or is it worse?

>> Dr. Prochaska: Few things in this world are as harmful as a combustible cigarette, that you’re lighting and burning and then inhaling the smoke so it should be that vaping is less harmful than a cigarette for the individual. Some caveats are that e-cigarettes are not well regulated so they come in very different shapes and forms. And they also haven’t been on the market for very long so we don’t have a solid understanding of their long-term effects. But when studies are done and look at the chemicals that are in the urine of individuals who vape vs smoke, those harmful factors that we see tend to be at lower levels among those who vape vs smoke.

>> Joe McIntyre: Now we all know that vaping and smoking are different. They physically look different when you’re smoking them. What is the chemical difference between vaping and smoking?

>>Dr. Prochaska: Because again you’re not burning, you don’t have carbon monoxide. So that's a key difference between the smoke versus the aerosol that you breath in. However, both can have volatile organic compounds, which we call VOC’s which contain cancer causing chemicals, heavy metals. And both have nicotine so that’s the addictive constituent in tobacco be it delivered from cigarette or from an e-cigarette.

>> Joe McIntyre: Now a myth that we see quite a lot online, and asked every so often on the Merck Manuals is this idea that vaping actually makes the smoker consume more nicotine than verses a typical cigarette. Is that true?

>>Dr. Prochaska: It all depends on how much you use it. So, e-cigarettes come in very different shapes and sizes and very different nicotine levels or different nicotine strengths. One that has been very popular in the marketplace including among youth is Juul. And a 5% Juul pod, which may sound like it’s not very high, is actually equal to a pack of cigarettes. And then again, it’s just a matter of how much you’re using it. For a young person to smoke a cigarette, parents are likely going to notice it, smell it. It is harsher to inhale, so it could be easier to secretly use the Juul Pod in that regard, get more nicotine than you might from a cigarette.

>> Joe McIntyre: So, it’s not necessarily apples to apples that one cigarette equals one puff or one whatever of a Juul. But it really depends on how much of that Juul or that vaping liquid that you consume.

>>Dr. Prochaska: Right and one pod would be equal to about 20 cigarettes. But it might look deceivingly less because it’s a smaller package to carry about so it’s a substantial high level of nicotine that you’re getting from the Juul. It can also be deceiving because again it’s a smoother way to inhale it. It’s often flavored. It used to be mango, cool cucumber, menthol mint. So, it can seem less harsh, easier to take more in then say from a cigarette.

>> Joe McIntyre: Now you just mentioned those flavorings whether it be mango or cucumber or caramel or whatever it may be. Do those flavorings actually add more harmful chemicals to vape pens then a cigarette would have? Or are those flavors more natural and are really not harming you all that much?

>>Dr. Prochaska: So, they’re not natural. They’re chemicals. And some of those chemicals have been shown to be cytotoxic, so harmful to cells in the lung tissue. An example would be diacetyl, which is the chemical that is used to create creamy flavors in e-cigarette devices. That was shown to create something called popcorn lung, which individuals who worked in the popcorn manufacturing plants were showing lung damage from inhaling that chemical. That is something that is unique to e-cigarettes than say cigarettes. However, cigarettes also have harmful additives that are added to them. Sugars, when they’re burned create aldehydes which are cancer causing. So, both being harmful.

>> Joe McIntyre: One question that we see asked quite often, is this idea that people who use vaping actually get more addicted to nicotine than those who smoke traditional cigarettes. Is that true or is that just a myth?

>>Dr. Prochaska: I would say we don’t quite know yet. You can’t randomize novices to e-cigs versus cigs, that would be unethical to initiate use of an addictive substance that can cause harm. So, we don’t have the kind of data you might like in terms of the randomized design and seeing over time who uses it more compulsively, has a difficult time quitting and so forth. What we are seeing is an uptake in e-cigarettes among young people to a far greater extent than they are using combustible cigarettes and that’s been the concern. And when you started off asking which is more harmful e-cigarettes versus cigarettes, at the individual level, if you take a chronic smoker and switch them completely to e-cigarettes that should be a good outcome, less harmful. But at a population level, there is the concern that e-cigs could be more harmful because we had seen such steady declines in smoking in young people and this is being reversed in terms of greater nicotine exposure because of e-cigarettes. So, the population level, we’re seeing greater nicotine exposure in young people than we would have seen otherwise.

>> Joe McIntyre: Now we mention young people here, and this could potentially be a scare tactic that parents use so correct me if I’m wrong. Is vaping more harmful to teens that it is to older adults?

>>Dr. Prochaska: I fully endorse that, yes. So, the developing brain, your brain continues to develop into the mid- 20's, in particular their frontal lobe region, which is where the decision-making capabilities and impulse control and kind of reward centers. So, you want to protect the brain until it’s fully developed because it’s still forming and prioritizing pathways. And when you introduce an addictive substance like nicotine or say cocaine or heroin all of those drugs operate on the same brain regions. And what happens is you see the kids find these drugs far more rewarding than natural rewards. So, if you put these kids in a brain scanner and you show them pictures of rewarding, tasty food versus say a cigarette, those who have smoked, their brains light up more for the cigarette visuals than for the food. The concern then is you start to prioritize these drugs over other things that would be rewarding in the environment.

>> Joe McIntyre: Now something that was introduced to cigarettes many years ago, I know this from watching way too many episodes of Mad Men, but this thought that filters when they were introduced to cigarettes, made them “safer” or protected the smoker from inhaling as many harmful chemicals. Do these filters do anything at all?

>>Dr. Prochaska: Filters were a technique to encourage consumers that this was a safer way to smoke. They come out, marketed to a greater extent in the 50’s where there's the cancer scare. There’s actually a quote in the tobacco industry documents that the illusion of filtration is just as important or even more important than whether it were to actually filter anything out. If filters were truly effective, you wouldn’t be able to bring any smoke in. And then furthermore, with filters, it’s been shown that you can breathe in smaller particles and you may be inhaling more deeply so those smaller particles are getting deeper into the lung tissue and causes cancers that are more difficult to find. So, filters do not provide any kind of health protection and if anything, more harm because people did not quit smoking and they continued to smoke and they may have gotten these different kinds of lung cancers.

>> Joe McIntyre: In many cases it’s the illusion of a safer alternative or a safer cigarette that may cause people to smoke even more thinking that they are ingesting fewer harmful chemicals when in fact they quite possibly be ingesting more.

>>Dr. Prochaska: Yes, that’s right.

>> Joe McIntyre: What are the risks of vaping things other than nicotine? I know some of these vape pens allow the smoker to ingest other things such as marijuana or otherwise. What are the risks associated with that versus nicotine?

>>Dr. Prochaska: Right. So, you have the potential harm of the substance that you are vaping. So, whatever that drug may be. The other more specific thing is that there are different cutting agents used for certain substances. For example, in cannabis, because it is lipid soluble it needs a fat to enter the bloodstream and the lung tissue whereas nicotine is water soluble it goes directly in. And one of the cutting agents that was being used was vitamin E and while it’s fine to ingest a pill, vitamin E as a supplement, it is not good to heat that up and create an aerosol and put it on your lung tissue. So, there were problems with lipoid pneumonia and people being put on lung machines and even deaths. This was termed as EVALI; E-cigarette vaping associated lung injury. So that was quite serious. That was about a year ago and those cases have gone down but is still very much advised that people be aware of what they’re vaping and to avoid in particular vitamin E.

>>Joe McIntyre: Did you know you can use to find in-depth content about hundreds of medical topics including those that may be difficult to spell? Simply browse by using the letter spine search function on our website. It’s the best, first place to go for easy-to-understand medical content.

>>Joe McIntyre: Now you had mentioned a little while ago that vaping would potentially be less harmful for a long-term smoker than smoking traditional cigarettes. As someone who’s an addiction expert, would you, I don’t know if the word is recommend, but would you say that vaping is an effective smoking cessation tool?

>>Dr. Prochaska: We don’t know. The jury’s still out. The way e-cigarettes came to the market in the U.S., there was some litigation against it to try and stop it because nicotine’s a drug and ultimately the courts allowed e-cigarettes to stay in the marketplace because they were deemed a tobacco product. It was stated further that to stay on the market they couldn’t make therapeutic claims, that is that they would help people quit, that it would be a treatment. If they were to make therapeutic claims, they’d need to have approval from the Food and Drug Administration as a therapeutic device. No e-cigarette company is the U.S. to date has been approved for that. You need randomized control trial data and that evidence in the U.S. has not been developed. Further as a researcher my hands are tied. I can’t conduct an RCT of e-cigarettes, randomized control trial because the companies would need to gain approval to do those kinds of studies. That said, there’s observational data. There are some people who quit with e-cigarettes. And there is a randomized control trial done in Britan recently that showed that e-cigarettes outperformed other forms of nicotine replacement therapy. The one caveat there is that at one year, among those who quit with e-cigarettes, 80% of them were still using those e-cigarettes. So, it might be that people are essentially transferring their addiction from cigarettes to e-cigarettes.

>>Joe McIntyre: So Dr Prochaska, why do people start smoking? And are there ways to prevent people from smoking before it happens. Either yourself individually or preventing others from smoking?

>>Dr. Prochaska: So why do people start smoking? Often, it is something you’re doing experimentally, maybe socially, you think it looks cool, someone you look up to, be it a role model, actor, actress, social media influencer. So, it looks like something fun and exciting and interesting to try. Which starts as experimenting, if you continue it, it does start to change your brain. What we see is these receptors in your brain Acetylcholine receptors, they upregulate. And they’re also called nicotinic receptors because nicotine binds to them. So, you get more of them in your brain that helps to unlock the neurochemical dopamine which is the feel-good hormone, which creates a surge, feeling of pleasure and so that feels great! Your brain lights up. The problem is that nicotine doesn’t last very long in the brain the half-life is about 2 hours, it goes away and your brain gets hungry for the nicotine. And so, what felt good, now feels badly and you become hungry, craving for that drug. So, what starts as experimenting becomes more of a behavior that you’re compelled to do. What started as a positive reward becomes more of a negative reinforcement where you’re using the drug so you don’t feel badly.

To prevent someone from smoking at the population level the efforts that have been done is to prevent the uptake among young people. As we discussed, the brain is developing so you want to put off any drug exposure until into the twenties and so now at the federal level, retailers cannot sell cigarettes to people under 21. And so that’s one effort. You can raise the price of cigarettes so that young people are priced out of it. You can regulate the advertising of cigarettes. So, it’s been off T.V. and radio since the early 70’s, whereas e-cigarettes are allowed to be on T.V. and radio so that’s something that could be curtailed in the U.S. Putting controls on social media and advertising and paying of influencers to promote product. Keeping cigarettes and e-cigarettes out of movies, out of video games. Keeping them out of the home. Another way to reduce the likelihood of people taking up cigarettes or e-cigarettes would be regulatory action to reduce the nicotine content, the actual nicotine that is in the rod of the cigarette or the level of nicotine that is provided in the e-liquid in e-cigarettes. And that is an effort that the Food and Drug Administration is reviewing.

>>Joe McIntyre: Now you mentioned advertising towards children and younger adults when it comes to vaping and e-cigarettes. And that’s obviously been curtailed a bit. But how do parents at the individual level, how should they talk to their children about what the dangers of e-cigarettes and vaping are. I think most of us have had conversations with our folks about the dangers of cigarettes and the dangers of alcohol, but vaping is a relatively new phenomenon for younger people. So how should parents approach that subject with their children?

>>Dr. Prochaska: I would encourage to approach it like you approach any other topic where you want to open dialogue. Open ended questions. Ask what your child understands about nicotine and e-cigarettes, anything they’ve learned in school. You can ask if their friends, if they’ve seen other kids using these products because that could be an indirect, effective way to get a sense of the extent to which your own child might be exposed to or using the drug. Get a sense of what they’ve heard about it and I would just be open and honest in terms of talking with them about potential harms and perceived benefits. I would not take a heavy hand on it. I would not be extreme in my approach to it. But rather would talk about, yes it might seem exciting and it might seem neat to blow these clouds of vaper. You may see popular kids using it, but what are the other potential consequences. It can be costly; it can be potentially harmful to your lung tissue to repetitively expose it to chemicals. And then also that you can get addicted to it. And so rather than being a behavior that you choose to do, it becomes a behavior that you feel forced to do. That you can’t concentrate unless you can get that next hit of nicotine. So just weighting the pros and cons of any behavior and any choice you might make.

>>Joe McIntyre: Now let’s say someone we know, or even ourselves personally has built up an addiction to e-cigarettes or to traditional cigarettes or nicotine in general, is there an effective way for this person to quit smoking? I know there’s been tons of remedies that I’m sure people have seen from gum to patches to going cold turkey. Is there an effective way to stop?

>>Dr. Prochaska: Yes, so there are effective treatments for quitting smoking. I can go over those. For e-cigarettes there’s not much out there in terms of research and treatment given that most clinicians are relying on what’s been shown to be helpful for quitting smoking and seeing if that works for quitting vaping. Proven for quitting smoking in adults, a combination of cessation medications with behavioral support. The medications include nicotine replacement therapies like gum, lozenges, patch, inhalers and nasal spray. There’s also a mouth spray that’s available outside the U.S. and likely to come to the market. There's medication, pills that you take to help with withdraw and block the reenforcing value of smoking if you do have a lapse. The behavioral counseling can be motivational. Most people want to quit smoking, 70%, and yet most fail. Only about 7 to 8 percent are successful in a given attempt. So, maintaining that motivation can be challenging. And also, behavioral strategies, essentially reengineering your environment, learning new coping strategies for dealing with stress and withdraw. No other drug is dosed as frequently as nicotine is with a cigarette or also now with vaping. So, that constant hit to the brain of nicotine, that reward, so many activities become conditioned to the drug nicotine. So, you get up in the morning, you take a hit. You drink your coffee; you take a hit. You’re driving the car you take a hit. And so, it’s deconditioning those behaviors so you’re not reaching for that cigarette or that e-cigarette and that’s the behavioral aspect of treatment.

>>Joe McIntyre: Now as we wrap up this episode, I want you to tell me if you can where individuals can go if they’re looking for information about how to stop smoking, how to quit, or how to talk to their children, or how to learn more about the dangers of e-cigarettes and vaping. Where should people go?

>>Dr. Prochaska: Online. Highly recommend the National Cancer Institute That’s a website. That's a texting program. It's apps. They have a quit line as well. They’ve got tailored content for teens, for women, for older adults, for veterans, in Spanish language. So, it’s a really excellent evidence-based resource for quitting smoking or helping people who you know to get treatment. The quit line, also highly recommend, that’s 1-800-QUIT-NOW. That’s a national number that when you call, you’re directed via your area code to your state resources. They provide counseling by trained coaches. They provide local referrals. Some countries provide free cessation medications. So that’s a great resource as well.

>>Joe McIntyre: And of course, Doctor Prochaska, as an author of the Merck Manuals, you recently released an editorial about just this topic, the dangers of smoking versus vaping which is available on and for those outside the U.S. and Canada.

Well Doctor Prochaska, thank you so much for joining us on this episode. I think it was really enlightening to hear, not just the dangers of smoking versus vaping, but how to quit and how to prevent people from starting these habits before they even begin. So, as a sign off, as we say at the Merck Manuals “Medical Knowledge is Power, Pass it On.” Thank you so much!

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Loss of Smell
Anosmia is the total loss of smell. Most people with anosmia can taste sweet, sour, salty, and bitter substances but cannot distinguish among specific flavors. This is because the sense of smell makes it possible to distinguish among flavors, not taste receptors as many people erroneously believe. Which of the following is NOT a common cause of anosmia?