How Dangerous Is Vaping?

E-cigarettes are loaded with potentially harmful chemicals—and the jury is out on whether they’ll help you quit smoking.

Medically reviewed in October 2021

Updated on October 15, 2021

We know cigarette smoking is bad; it's the leading cause of preventable death. In fact, lighting up causes more than 7 million deaths worldwide each year.

In recent years, vaping has been touted as a safer alternative to smoking cigarettes, and even as a method to help quit. But is vaping really any safer?

A brief history of vaping
Vaping refers to the use of electronic cigarettes (or e-cigarettes) and similar handheld devices that heat and vaporize liquids for users to inhale. In addition to tobacco, e-cigarettes can also be used to smoke marijuana.

Vaping liquids typically contain nicotine, flavor enhancers, and chemicals like propylene glycol. The exact combination of ingredients varies according to brand and flavor, although package labels aren’t always accurate. In fact, some products that claim to be nicotine-free have been found to contain the substance.

“Until we actually have U.S. Food and Drug Administration (FDA)-approved studies, there really is no consistent way for consumers to know exactly what they’re getting,” says Susan Garwood, MD, a pulmonary critical care physician at TriStar Centennial Medical Center in Nashville. That lack of transparency, along with concern over the safety of chemical ingredients, sparked demand for FDA regulation of vaping products in 2016. In response, the agency announced that vape companies would have to start submitting their products for approval by August 2016.

Two years later, the FDA took further regulatory steps. In August 2018, the agency announced it was cracking down on companies that make or sell vape products packaged to resemble kid-friendly treats, like juice boxes and candies. Advertising tobacco products in ways that appeal to kids violates the Federal Food, Drug, and Cosmetic Act.

Then, in January 2020, the FDA announced a ban on marketing and distributing prefilled, flavored e-cigarette products aside from menthol and tobacco. Refillable and cheap disposable vape cartridges (pods) were not prohibited, however, leaving the door open for use of flavored e-liquids (also called vape juice).

But October 2021 brought on a big change. That’s when, for the first time, the FDA permitted marketing of three e-cigarette products to help adult smokers wean themselves off tobacco. In studies, smokers successfully used certain Vuse Solo devices to reduce or quit cigarettes, according to an agency press announcement.

It should be noted that the FDA didn’t give approval for these items—which would have signified an endorsement of tobacco use—but rather an authorization, which only allowed specific products to hit shelves for a specific use. In fact, the agency was careful to note that tobacco products are both harmful and addictive, and that Vuse will be carefully monitored to ensure it follows FDA marketing requirements. If it doesn’t, the authorization can be taken back.

In the meantime, there is still much to be learned about the safety of electronic cigarettes, but here's what we do know. 

What’s in your e-cigarette?
You might not know what you’re inhaling with each puff. Here are some common ingredients and how they affect your body.

Nicotine: The majority of vaping liquids contain nicotine. More research on the long-term effects of e-cigarettes is needed, but we already know the nicotine content in vaping liquids can pose health risks. Nicotine elevates the heart rate, is highly addictive, and is associated with impaired cognitive development among adolescents.

Parents must keep vaping devices out of reach of children, says Dr. Garwood, since ingesting even a few drops of the liquid can be dangerous and even deadly. In 2016, Congress passed legislation requiring child-resistant packaging for vaping liquids, but many cartridges can still be opened by curious kids. Between January 2012 and April 2017, more than 8,200 cases of exposure to liquid nicotine in children under 6 were reported, according to an analysis published in Pediatrics in May 2018.

Vaping is also unsafe during pregnancy. “Somehow I think society sees e-cigarettes as more acceptable for pregnant women to use. That is not the case," notes Garwood. Nicotine can cause low birth weight and other pregnancy complications, such as brain and lung damage.

Flavor enhancers: From cinnamon roll to pink lemonade, the flavor possibilities of vape juice are seemingly endless. In addition to posing a potential carcinogen risk, these liquids present a higher risk of inhalation damage, Garwood says.

Chemicals: E-cigarettes often contain an array of chemicals that become toxic when heated. Propylene glycol, for instance, turns into formaldehyde at high temperatures. Formaldehyde—a naturally occurring chemical often found in building materials and household cleaners—is a known cancer-causing agent that can trigger asthma and affect lung function.

Research published in Scientific Reports in May 2018 suggests e-cigarettes contain more formaldehyde than previously believed. The amount users inhale varies according to brand, flavor, and the size and frequency of puffs, but some research suggests it’s possible to get more formaldehyde from e-cigarettes than from traditional smoking.

“It depends on how long it takes you to ingest the 3 milliliters of liquid," says Garwood. She explains that if you're puffing through a whole cartridge in a day, you may get substantially more formaldehyde than from a pack of cigarettes. It depends in large part on the e-cigarette battery voltage.

Who is using e-cigarettes?
Electronic cigarettes have become the most commonly used tobacco products among teens, despite age restrictions that state a person needs to be 18 years old to purchase these devices. In 2021, a report from the Centers for Disease Control and Prevention found that about 2 million middle and high school students in the United States reported using e-cigarettes within the previous 30 days, including 2.8 percent of middle school students and 11.3 percent of high schoolers.

As for adults, about 4.5 percent used e-cigarettes in 2019. More than 76 percent of them were current or former regular cigarette smokers. The rest—about 24 percent—had never been regular cigarette smokers.

Can vaping actually help you quit smoking?
Though the FDA authorized the use of specific e-cigarette devices for use as quit aids in October 2021, vaping is not officially approved by the agency or supported by the American Lung Association (ALA) as a safe way to taper off cigarette use. In fact, the ALA did not support the FDA’s decision on Vuse Solo products. The U.S. Preventive Services Task Force also says evidence isn't sufficient to recommend e-cigarettes as part of a healthy quit plan and that more research is needed.

While some studies are promising—including the research used by the FDA to justify their Vuse approval—many other studies are not as supportive. For example, a September 2020 study of 2,800 smokers published in PLOS One discovered no evidence that vaping is a helpful quit aid. Researchers found that one to two years after quitting, those who used e-cigarettes had similar success rates as those who used approved quit aids or nothing at all.

Since e-cigarettes are largely not authorized for smoking cessation, there aren’t well-defined tapering strategies in place for using these devices like there are with other quit aids. The amount of nicotine users inhale isn’t typically controlled, and it may not decrease over time. Instead, it varies according to the size and frequency of puffs. In fact, “people may actually be getting more nicotine because of the way they use the devices,” Garwood says.

So, is it safe to vape?
More studies are needed to learn the lasting effects of vaping on your health. That said, a growing pile of research suggests that e-cigarettes are linked to multiple illnesses, including breathing issues like asthma and chronic obstructive pulmonary disease (COPD).

For example, one 2020 study in the American Journal of Preventive Medicine found that subjects who used e-cigarettes alone had a 75 percent greater risk of developing COPD compared to those who never smoked. Daily users also had a 73 percent higher chance of asthma, compared to nonsmokers. Current and former smokers of traditional tobacco had higher odds of COPD, as well.

An increased cancer risk is plausible, as well, though not conclusively proven. In general, there are fewer harmful chemicals in e-cigarettes compared to traditional cigarettes, although the amount of exposure varies with brand and user habits. Preliminary studies suggest some brands contain cancer-causing chemicals like nitrosamines and carbonyl compounds, in addition to formaldehyde.

“If you had an option not to be exposed to carcinogens at all, wouldn’t you choose that?” asks Garwood.

That’s not all. In 2019 and early 2020, more than 2,800 ER visits and upwards of 60 deaths were associated with a condition known as e-cigarette (or vaping) product use-associated lung injury (EVALI). Officials linked the deaths to THC-containing e-cigarettes and an additive called vitamin E acetate. Enforcement and awareness helped to tamp down the outbreak, but the crisis pointed to the need for strong, continuing regulation.

Bottom line: Many e-cigarettes look to be ineffective quit aids and are likely harmful to your health. If you smoke them already, ask your healthcare provider about kicking the habit. And if you don’t? There’s no good reason to start.


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