By Gail D’Souza
The year is 2060. Scientists are recruiting former e-cigarette smokers to a study to examine the long-term effects of electronic cigarette (e-cigarette) smoking. You think to yourself, “Well, I smoked back in 2020, so how could that affect me 40 years later?” Regardless, you sign up for the study, and the researchers inform you that new evidence supports various long-term harmful effects of e-cigarettes. You think to yourself, “I wish someone informed me about this years ago.”
Cigarette smoking has been a public health concern for decades and continues to be a topic of interest due to its harmful effects.1 Although cigarette smoking has declined from 20.9% in 2005 to 14.0% in 2019, more than 16 million Americans live with a smoking-related disease.1 To put this into perspective, cigarette smoking causes more than 480,000 deaths in the United States annually and is the leading cause of preventable death.2 While most individuals are aware of the harmful effects of cigarette smoking, there is very little known about the health effects from the use of e-cigarettes (also called “vaping”).2
So, what are those funky devices that allow people to smoke at any time without using a lighter? E-cigarettes, also known as e-cigs, vapes, vape pens, JUULs, or electronic nicotine delivery systems (ENDS), are battery-operated devices that, unlike a traditional cigarette, burn a liquid within the device to produce an aerosol inhaled by the user.1 The liquid may contain nicotine, flavorings, or other additives that have become increasingly popular in youth and adults since 2003.3 In 2018, over 8 million adults and 3.6 million US middle and high school students were e-cigarette users.1 This constitutes about 4.9% of middle school students and 20.8% of high school students in the US.1 Reasons for high e-cigarette usage in youth include the sleek designs, fun flavors, ability to hide them easily, and ability to smoke anywhere with the click of a button. E-cigarettes vary in design with some looking similar to cigarettes and pipes, to others resembling USB flash drives, pens, or other ordinary items that youth perceive as cool.4 In the past decade, tobacco companies have developed several e-cigarette products (Figure 1) and marketed e-cigarettes as a safer alternative to smoking. Although e-cigarettes do not contain the 7000+ harmful chemicals that traditional cigarettes do, we do not fully understand the harmful effects of e-cigarettes.1,5
Scientists are consistently exploring the effects of vaping, and here is what we know so far. Although vaping is less harmful than smoking traditional cigarettes due to the inhalation of fewer toxic chemicals, vaping is still not 100% safe.6 In August 2019, an increase in emergency department visits was recorded due to “e-cig, vaping, or product use-associated lung injury (EVALI)”.7 EVALI was strongly linked to vitamin E acetate, an additive found in some tetrahydrocannabinol-containing e-cigarettes, black market obtained vaping products, or modified e-liquids. Vitamin E, frequently found in foods and skin care products, does not cause harm when ingested or applied topically, but research suggests that it may interfere with normal lung function when inhaled.7 Vitamin E acetate may interact with phospholipids and surfactants of the epithelial lining fluid, causing an inflammatory response.8 The epithelial lining fluid protects the airway mucosa from irritants and pathogens by forming a barrier against the external environment. Thus, interaction with this fluid may lead to decreased lung function which is also seen in cigarette smokers.8,9
Smoking and vaping cause similar health complications, such as an increased risk of myocardial infarction, chronic obstructive pulmonary disease, stroke, and other respiratory diseases.10 This is due to the presence of particulate matter (PM) generated from e-cigarettes as well as nicotine (which is a highly addictive compound).10,11 Although PM in e-cigarettes are present in varying amounts, the contents may be similar to cigarettes like carbon monoxide, acetaldehyde, hydrogen cyanide, acrolein, and carbonyl compounds.11,12 These PM consist of varying sizes, including ultrafine particles which can deposit deep in the lungs and are associated with respiratory diseases, epigenetic modifications like alterations in expression of noncoding RNAs, and dysregulation in gene expression (Figure 2).12 Nicotine, on the other hand, releases rewarding neurotransmitters in the brain like dopamine, making users feel more alert immediately but overtime changing brain chemistry causing users to crave it more.12,13 Additionally, the US Surgeon General confirmed in his annual report that nicotine exposure during adolescence can uniquely harm the adolescent brain and have effects on brain development.13
Despite the numerous harmful effects of vaping, scientists have also found some advantages of vaping when used by current cigarette smokers for smoking cessation.14 Some cigarette smokers feel that e-cigarettes have the potential to benefit them if used as an alternative to smoking traditional cigarettes.14 A randomized controlled trial conducted in 2019 found that smokers were more likely to abstain from cigarette smoking when randomized to e-cigarettes containing nicotine (18%) vs. patients who used nicotine replacement therapies (NRT) (9.9%). This may be due to the e-cigarette group (80%) continuing to use their assigned product as opposed to the participants using NRT (9%) for one year.15 E-cigarettes have not yet been approved by the FDA for smoking cessation due to conflicting results from clinical and observational studies. Thus, clinicians generally prescribe traditional nicotine replacement therapies before exploring e-cigarettes as a method for smoking cessation.1,3,4.
Scientists are still learning about the long-term effects of e-cigarettes and have found that they are not safe for youth, young adults, pregnant adults, or adults who do not currently use tobacco products.1, To break this into simpler terms, although e-cigarettes have the potential to benefit some individuals (who use e-cigarettes as a smoking cessation tool), vaping tends to be harmful due to their effects on lung function, risk of heart disease, and development of brain and respiratory diseases, especially for youth and young adults. It has taken scientists over 50 years to analyze and research the harmful effects of smoking, so we are still at the beginning of understanding the harmful effects of e-cigarettes. Future research must be directed towards understanding the long-term health effects of vaping, so we can prevent potential health issues. The bottom line is, if you have never smoked tobacco products or e-cigarettes before, it is probably wise not to start vaping.1 If you ever see yourself signing up for an e-cigarette study in 2060, I do hope this article comes to mind!
- Drummond MB, Upson D. Electronic cigarettes. Potential harms and benefits. Ann Am Thorac Soc. 2014;11(2):236-242. doi:10.1513/AnnalsATS.201311-391FR
- Fadus MC, Smith TT, Squeglia LM. The rise of e-cigarettes, pod mod devices, and JUUL among youth: factors influencing use, health implications, and downstream effects. Drug and alcohol dependence. 2019 Aug 1; 201:85-93.
- 5 Vaping Facts You Need to Know [Internet]. 2021 [cited 15 March 2021]. Available from: https://www.hopkinsmedicine.org/health/wellness-and-prevention/5-truths-you-need-to-know-about-vaping
- Centers for Disease Control and Prevention. 2021 [cited 14 March 2021]. Available from: https://www.cdc.gov/tobacco/basic_information/e-cigarettes/severe-lung-disease.html
- Chand HS, Muthumalage T, Maziak W, Rahman I. Pulmonary toxicity and the pathophysiology of electronic cigarette, or vaping product, use associated lung injury. Frontiers in pharmacology. 2020 Jan 14; 10:1619.
- Epithelial Lining Fluid – an overview | ScienceDirect Topics [Internet]. Sciencedirect.com. 2021 [cited 17 March 2021]. Available from: https://www.sciencedirect.com/topics/medicine-and-dentistry/epithelial-lining-fluid
- Glantz SA. The evidence of electronic cigarette risks is catching up with public perception. JAMA network open. 2019 Mar 1;2(3): e191032-.
- Blount BC, Karwowski MP, Shields PG, Morel-Espinosa M, Valentin-Blasini L, Gardner M, Braselton M, Brosius CR, Caron KT, Chambers D, Corstvet J. Vitamin E acetate in bronchoalveolar-lavage fluid associated with EVALI. New England Journal of Medicine. 2020 Feb 20;382(8):697-705.
- Traboulsi H, Cherian M, Abou Rjeili M, Preteroti M, Bourbeau J, Smith BM, Eidelman DH, Baglole CJ. Inhalation toxicology of vaping products and implications for pulmonary health. International Journal of Molecular Sciences. 2020 Jan;21(10):3495.
- US Department of Health and Human Services. E-cigarette use among youth and young adults: a report of the Surgeon General pdf icon[PDF–8.47 MB]. Atlanta, GA: US Department of Health and Human Services, CDC; 2016.
- Fu R, O’Connor S, Diemert L, Pelletier H, Eissenberg T, Cohen J, Schwartz R. Real-world vaping experiences and smoking cessation among cigarette smoking adults. Addictive Behaviors. 2021 May 1; 116:106814
- Hajek P, Phillips-Waller A, Przulj D, Pesola F, Myers Smith K, Bisal N, Li J, Parrott S, Sasieni P, Dawkins L, Ross L. A randomized trial of e-cigarettes versus nicotine-replacement therapy. New England Journal of Medicine. 2019 Feb 14;380(7):629-37.