The safety and long-term health effects of using e-cigarettes or other vaping products are still not well known. In September 2019, federal and state health authorities launched an investigation outbreak of a serious lung disease associated with e-cigarettes and other vaping products. We are closely monitoring the situation and will update our content as soon as more information is available.

Vaping, the act of evaporating a liquid to inhale, is an increasingly popular alternative to cigarette smoking. However, it can damage health by irritating the lungs and throat and introducing toxins into the body.

Some vape product manufacturers claim that vaping is a completely safe alternative to smoking. Early research on the safety of the practice, however, suggests that this is not the case. In fact, it appears that vaping, even without nicotine, can have detrimental effects on the body.

This article discusses current research on the side effects of nicotine-free vaping.

E-liquid refers to the liquid that vaporizes vape devices or electronic cigarettes. People can also call it e-juice or vape juice. The side effects that a person experiences when he or she fumes depend in part on the type of e-liquid they use.

The specific components of e-liquids differ between brands and products. The base fluid is usually a mixture of ingredients such as water, vegetable glycerin and propylene glycol. Manufacturers then add different flavorings or additives to this blend to create a specific flavor.

Many of these ingredients have a Generally recognized as safe (GRAS) certification – a Food and Drug Administration (FDA) designation – for use in food products. However, the evaporation process heats and evaporates these ingredients, and there is little research to suggest that food grade ingredients are safe for evaporation.

In addition, the Centers for Disease Control and Prevention (CDC) mentions that vape aerosol may contain dangerous substances other than nicotine, including:

  • diacetyl, which is associated with lung disease
  • heavy metals such as nickel, tin and lead
  • other volatile organic compounds

Nicotine-free vaping prevents nicotine dependence and other nicotine-related side effects.

However, nicotine-free vaping can also cause side effects, including those listed below.

General toxicity

Many of the chemicals in e-liquids can have toxic effects on the body. A 2012 laboratory study found that these effects were not due to nicotine, but to the chemicals manufacturers use to flavor e-liquids. It is important that this was also the case for e-liquids that consisted of food grade ingredients.

A 2015 study showed that heating the propylene glycol and glycerol in e-liquids creates compounds that release formaldehyde. According to the International Agency for Research, formaldehyde is a Group 1 carcinogen, meaning it has the potential to cause cancer. A more recent study examined the effects of e-liquid on young vape users.

The study compared three groups of adolescents:

  • those who used only e-cigarettes
  • those who used e-cigarettes in addition to smoking standard cigarettes
  • and those who have never used

In general, the study showed that vaping was less harmful than cigarette smoking. However, adolescents in the e-cigarette only group had significantly greater amounts of toxic chemicals in their urine compared to those in the control group. These chemicals included:

  • acrylonitrile
  • acrolein
  • propylene oxide
  • acrylamide
  • crotonaldehyde

Other research supports these findings, showing that heating and evaporation of e-liquid chemicals make them particularly toxic to lung cells. Consequently, the researchers warn “against the widespread belief that e-cigarettes are safe.”

In addition, some vape manufacturers add vitamin E acetate to vapor fluids containing tetrahydrocannabinol – a cannabinoid commonly known as THC – to thicken or dilute it. According to a 2019 study, vitamin E acetate is a tough substance that has associations with lung injury.

Lung and throat irritation

In the short term, steaming e-fluid can irritate the lungs and throat. People who vape often refer to this as a “throat stroke”. This term describes the tingling, burning sensation a person experiences when inhaling the vapor.

This sensation comes from heating and inhalation of the chemicals in the e-liquid. Like the authors of a 2015 study note, inhalation of large amounts of propylene glycol and glycerol may irritate the airways. They also point out that the levels of these chemicals in the e-cigarette are high enough to cause irritation after just one puff.


A 2018 study found that several common e-liquid fragrance ingredients caused a damaging inflammatory response in lung cell samples. The e-fluids examined in the study did not contain nicotine.

Chronic inflammation of lung tissue can lead to irreversible lung scarring.

Larger scale studies in humans will help determine the long-term risks that e-liquid vapors pose to lung tissue. Early evidence, however, suggests that they negatively affect these organs.

Many people say vaping helps them resist the urge to smoke cigarettes. Vaping, however, carries risks, even without nicotine.

With that in mind, individuals can look for alternatives to vaping that meet some of the things they enjoy from the habit. Some examples include:

  • Drink sparkling water: The tingling, burning sensation of drinking a carbonated beverage can cause a sensation that looks like a cold hit.
  • Chewing gum: Chewing gum with flavored chewing gum, with or without nicotine, can provide a fragrance experience similar to that of vaping.
  • Play with a toothpick: Holding a toothpick in the mouth helps to divert attention from the hands and mouth, which can reduce or remove a person’s urge to smoke or steam.
  • Eat sunflower seeds: Eating sunflower seeds requires a person to repeatedly put their hand to their mouth. This repetitive motion mimics the movements an individual makes when wearing a vape, which can help alleviate the urge to vape.
  • Take a deep breath: The use of a vape often requires a person to breathe very deeply that they would not otherwise be allowed to ingest. Taking several very deep breaths can help reduce the urge to vaporize.

A large amount of research focuses on the negative effects of cigarettes. This evidence is one reason why vaping has become popular in the first place.

The CDC notes that cigarette smoking causes more than 480,000 deaths each year in the United States, making it responsible for nearly 20% of all deaths. Therefore, the risks of cigarette smoking are very likely to outweigh the risks of vaping without nicotine.

However, many manufacturers falsely claim that their vape products are completely safe. On the contrary, a growing body of evidence suggests that vaping also poses health risks.

Scientists still have to conduct large-scale studies over many years to fully understand the long-term risks of vaping. Despite this, initial research suggests that vaping with or without nicotine is harmful to the body.

Yet a 2019 study shows that vaping may be a more effective method of quitting smoking compared to other nicotine replacement methods.

Vaping can have many side effects, even when the e-liquid does not contain nicotine. Despite being classified as a food grade ingredient, the flavorings and additives in e-liquids can have numerous harmful effects on the body when a person heats and evaporates them.

Research shows that the chemicals in e-fluid can have particularly detrimental effects on lung tissue. Heating of these chemicals can also cause the release of carcinogens.

Research on the safety of vaping is still in its early stages, and large-scale studies are needed to determine the long-term risks. However, early research shows that vaping, even without nicotine, is not a completely safe alternative to cigarette smoking.