Nicotine-free fluids may seem safer than nicotine-based products, but side effects are still possible. Your individual risk ultimately depends on the product’s base fluid, flavoring, and other ingredients.

We still don’t know much about vaping and e-cigarette use. Research into short- and long-term effects is ongoing.

That said, it’s clear that vaping has side effects, regardless of whether the vape fluid contains nicotine. Here’s what we currently know about the side effects of vaping different fluids.


When heated, components in vape juice may irritate the mouth and airways.

One 2015 study found that one puff from a nicotine-free shisha pen contained enough propylene glycol and glycerol, two common base liquids, to cause irritation.

When vaporized, these substances may potentially form cancer-causing compounds.


Nicotine-free vaping also appears to trigger an immune system response. One 2018 in-vitro study found that exposure can cause an inflammatory response in immune system cells.

An inflammatory response that may be most prominent with vaping is within the lungs or throat. Heavy use of vaporizers could cause an inflammatory response throughout the body.

Another 2018 in-vitro study concluded that exposure to e-juice flavoring compounds may activate an inflammatory response in certain white blood cells. This can affect how these cells work within your immune system.


In addition, nicotine-free e-cigarette liquid may be toxic to cells.

The same 2018 in-vitro study found that exposure to e-cigarette vapor led to cell death even when nicotine wasn’t present. The affected cells reside in the lungs and are meant to defend your body against toxins, infectious particles, and allergens in the air you breathe.

A third 2018 in-vitro study found that exposure to flavoring additives in e-cigarettes can harm blood vessel cells in the heart, which are known to play a role in long-term heart health.

The death of these cells can lead to vascular conditions, such as high blood pressure, diabetes, and heart disease.

There’s a substantial amount of research documenting the harmful effects of nicotine, though most studies focus on nicotine exposure from smoking tobacco.

For example, nicotine use can increase your risk of respiratory, heart, and digestive illnesses. It’s also associated with a weakened immune system and a decline in overall reproductive health.

Nicotine has cancer-causing properties. It’s also addictive.

Although research is limited, some studies have compared the effects of nicotine-free e-cigarettes and those that contain nicotine.

A smaller 2015 study of 20 participants compared the 24-hour effects of using a nicotine-free e-cigarette among participants who smoked cigarettes and participants who previously abstained from cigarettes or vaping.

One 2015 study found that people who used e-cigarettes containing nicotine reported greater dependence than those who used nicotine-free e-cigarettes.

The researchers reported no immediate change in lung function among the participants who previously abstained. They reported a small negative effect on lung function among participants who smoked cigarettes.

In addition, one 2018 study found that vaping fluids with nicotine caused a significant increase in blood pressure. This increase lasted for about 45 minutes after vaping.

The Centers for Disease Control and Prevention (CDC) report that smoking cigarettes has wide-ranging negative effects on health, including increased risk of heart disease, stroke, and cancer.

Cigarette smoking is the number one cause of preventable deaths in the United States.

Vaping nicotine-free fluids may be associated with fewer health risks than smoking cigarettes. However, it’s important to recognize that there are risks associated with both nicotine-free and nicotine-containing e-cigarettes.

Some people use vaping as a tool to quit smoking cigarettes.

If you don’t currently smoke cigarettes, vaping might increase — rather than decrease — your overall risk of adverse effects.

Certain vape fluid flavors are associated with harmful side effects. In one 2016 study, researchers tested 51 different vape juice flavors for three potentially harmful chemicals:

  • diacetyl
  • acetylpropionyl (2,3-pentanedione)
  • acetoin

They found one or more of these chemicals in 92 percent of the flavors tested. In addition, 39 of the 51 flavors tested contained a concentration of diacetyl that was over the laboratory limit.

Diacetyl is used in buttery or creamy flavors. When inhaled, it’s associated with serious respiratory illnesses.

In a 2018 study, researchers found that cinnamaldehyde, or cinnamon flavoring, had the most significant toxic effects on white blood cells.

O-vanillin (vanilla) and pentanedione (honey) also had significant toxic effects at the cellular level.

The Food and Drug Administration (FDA) regulates vaping devices and liquids, including those that don’t contain nicotine.

Manufacturers must include a warning label on all products containing nicotine.

Some potentially harmful flavoring chemicals found in vape fluids, in addition to the ones mentioned above, include:

  • acrolein
  • acrylamide
  • acrylonitrile
  • benzaldehyde
  • citral
  • crotonaldehyde
  • ethylvanillin
  • eucalyptol
  • formaldehyde
  • propylene oxide
  • pulegone
  • vanillin

Manufacturers aren’t required to provide consumers with a list of e-liquid ingredients, which can make it hard to know which products to avoid.

You may find it easier to avoid flavors that are frequently associated with respiratory irritants. This includes:

  • almond
  • bread
  • burnt
  • berry
  • camphor
  • caramel
  • chocolate
  • cinnamon
  • clove
  • coffee
  • cotton candy
  • creamy
  • fruity
  • herbal
  • jam
  • nutty
  • pineapple
  • powdery
  • red hot
  • spicy
  • sweet
  • thyme
  • tomato
  • tropical
  • vanilla
  • woody

Cannabis vaporizers don’t contain nicotine but can still cause side effects. These side effects are generally caused by tetrahydrocannabinol (THC), the active ingredient in cannabis.

The high associated with vaping cannabis might be stronger than the high that results from traditional toking. Other potential side effects include:

  • memory impairment
  • impaired coordination
  • difficulty problem-solving
  • sensory and mood changes
  • nausea
  • vomiting
  • increased heart rate

Vaping flavored cannabis oil may also lead to side effects similar to those of nicotine-free e-cigarettes, depending on the fluid’s base and flavoring ingredients.

CBD vaporizers don’t contain nicotine but can still cause side effects.

CBD stands for cannabidiol, one of several active ingredients in cannabis. Unlike THC, CBD isn’t psychoactive, which means it doesn’t cause a mental “high.”

While there’s little research on the side effects of vaping CBD, some general side effects — which tend to be mild — of CBD use include:

  • irritability
  • fatigue
  • nausea
  • diarrhea

Vaping flavored CBD oil may also cause side effects similar to those of nicotine-free e-cigarettes, depending on the fluid’s base and flavoring ingredients.

Juuling is another term for vaping. It refers to the use of a particular e-cigarette that looks like a USB key and is popular among young people.

Most Juul products contain nicotine. The side effects described in this article surrounding nicotine also apply to Juuling.

Make an appointment with a doctor or other healthcare professional if you experience any of the following:

A clinician can assess your symptoms and determine whether they’re the result of vaping or an underlying condition.

Consider consulting a healthcare professional if you’re trying to cut back on smoking or vaping. They can help you understand how to decrease your nicotine intake and ultimately quit altogether.