Vaping and Children: What the Evidence Reveals About E-Cigarette Health Risks

Electronic cigarettes, or vapes, were introduced in the 2000s as a tool to help people quit smoking—a dangerous habit that kills half of all lifetime users.¹ Public-health messaging has supported the view that e-cigarettes are 95% safer than traditional cigarettes (go.nature.com/4ixya3r). Manufacturers and some physicians have also highlighted the advantages of electronic nicotine-delivery systems for people who already depend on nicotine.

However, the safety of e-cigarettes is not well established, and even the evidence behind the 95% claim is difficult to pinpoint. Health concerns related to vaping began to emerge more than a decade ago. As e-cigarette use has become more widespread, evidence of potentially harmful effects has continued to grow.

In particular, e-cigarettes have become an attractive gateway to nicotine addiction for non-smokers, including children.

A systematic review published in August, of which we are co-authors, identified a range of health effects associated with vaping among children and young people.² The range of possible harmful effects is wider than expected and is becoming increasingly evident among the children we see in hospitals.

Here, we outline the health risks of vaping among children and young people and explain why governments may need to take legislative action to ensure that existing laws are effectively enforced.

How e-cigarettes deliver nicotine

By design, e-cigarettes efficiently release nicotine at levels comparable to or higher than those delivered by typical cigarettes.³ This efficiency may help explain why e-cigarettes are effective quitting aids for some smokers. Meta-analyses have found them to be more effective than some other nicotine-replacement therapies as a means of quitting smoking.⁴ However, e-cigarettes are not without risks.

Nicotine is highly addictive. Decades of research in smokers have shown that it can negatively affect brain development in fetuses and adolescents.⁵⁶ Even intermittent exposure at low levels can quickly cause symptoms of nicotine dependence.⁷ These effects are particularly noticeable during adolescence, when some young users report cravings and withdrawal symptoms after occasional exposure.⁸

E-cigarettes can contain harmful substances, including heavy metals such as lead, toxic carbonyls, nanoparticles and unregulated substances such as synthetic cannabinoids.⁹ Although the long-term health consequences are not yet fully known, these substances are associated with pro-inflammatory, immunosuppressive, carcinogenic and addictive effects.

Why nicotine salts may increase vaping appeal

Since e-cigarettes were developed, their use has continued to increase, coinciding with the renewed use of nicotine salts. In the 1970s, manufacturers improved processing techniques to remove protons and organic acids from naturally occurring nicotine salts. The resulting unbound, or freebase, nicotine has no electrical charge and is attracted to fat. These chemical properties allow faster absorption and transfer to the brain, creating a more intense sensory experience, or nicotine “hit.”¹⁰

In 2017, e-cigarette manufacturers began using salt-based nicotine because it tasted smoother and sweeter. Adding these salts to vape liquids improved the sensory experience, particularly for people who had never smoked and were not accustomed to inhaling freebase nicotine.¹¹

Research has shown that some nicotine-salt products can produce higher and faster peaks in blood nicotine levels.¹² Vape manufacturers have also made these products appealing to younger users through sweet and fruity flavors and colorful packaging.

Health risks of e-cigarettes in children and young people

Early research into the potential risks of e-cigarettes across age groups focused on acute effects, including an immediate decline in lung function and the development of respiratory symptoms.¹³ These effects may represent only part of the overall harm associated with vaping at a young age. Our systematic review identified a concerning range of potential health risks.

Respiratory, oral and eye symptoms

As respiratory pediatricians, we were not surprised to find that vaping during childhood was consistently associated with coughing, chest discomfort, wheezing and wet cough. The studies we reviewed also reported increases in oral and dental problems, including gum inflammation, ulcers and dry mouth.

Eye symptoms—including itching, redness, dryness, blurred vision and pain—may result from the direct effects of inhaling hot gases and chemicals. An increase in allergic diseases, including atopic dermatitis and allergic rhinitis, has also been reported.

Mental health and nicotine dependence

Nicotine is a powerful stimulant of the central nervous system, so we expected vaping to affect more than the respiratory system. However, we were surprised by the extent to which vaping among young people was associated with poorer mental health.

Depression, panic disorder, anhedonia and suicidal ideation are all reported more commonly among people who vape. Young e-cigarette users are almost twice as likely as non-users to report suicidal thoughts, plans or attempts.

Pregnancy and infant health

We were also concerned that vaping might negatively affect the fetus. Our study found that infants born to mothers who smoked e-cigarettes had higher rates of preterm birth, low birth weight for gestational age, abnormal reflexes and motor immaturity.

Vaping and later cigarette smoking

One of the most worrying findings was strong evidence that vaping predicts and increases the likelihood of subsequent traditional smoking among children and young people who have never smoked. E-cigarette users were typically two to 12 times more likely to start smoking later than non-users.

This return to dangerous practices is especially concerning because children born after the turn of the millennium had begun to make healthier choices. In 2018, the UK media dubbed 16- to 24-year-olds the “Enlightened Generation” as alcohol consumption, drug use, teenage pregnancy, criminal activity and smoking decreased dramatically.

Balancing smoking cessation benefits with risks to youth

Although e-cigarettes can be useful as an adjunct to smoking-cessation programmes for adults, their unsubstantiated and simplistic promotion as a safe alternative to cigarettes has unintended consequences for non-smoking children and young people.

The rise of e-cigarette use among children and young people is a global phenomenon spanning continents and markedly different cultures.¹⁴ The duration of vaping varies by country.