What Is In Vape Juice?

By Dr. Annie Macpherson
Updated: 2019-09-14

What is in vape juice, e-juice, and e-liquid?

What’s in vape juice?


E-juice, and e-liquid are all interchangeable terms for the liquid you use to create vapor from your e-cigarette. E-juice is made up of vegetable glycerin (VG) or propylene glycol (PG), water, nicotine, and food grade flavorings.

Often, e-juices are made with a 90:10 content ratio of PG/VG to flavourings and nicotine, but this can vary.

Vegetable Glycerin Vs. Propylene Glycol

The Difference Between The Two


VG and PG have a variety of different properties. Some premium e-juices will offer hybrids of PG/VG of varying ratios; it is up to you to find out what suits you best. We’ve summarised their different properties below:

Vegetable Glycerin (VG) Propylene Glycol (PG)
Vegetable Based Used in food colourings, flavourings and medicines
Bigger vapor cloud Better throat hit
Thicker in consistency – can be gunky, reducing lifespan of atomizer Thinner than VG – easier for atomizer wick to absorb
More gunk and build up Cleaner vaping as less build up
Sweet tasting – will affect e-juice flavour Flavorless
Less allergic reactions Some allergic reactions reported

VG Pros:

They have the capacity to produce a large vapor.

VG Cons:

It doesn’t leave the same flavor. It can be sweeter for almost every flavor.

PG Pros:

It’s safer to use for inhalation or swallowing.

PG Cons:

Compared to VG, this one produces less vapor. Not ideal for massive clouds.


Coffee and Lemon Juice

What defines the quality of an e-juice

As well as the base (PG or VG), e-juices contain flavourings. Generally, the flavouring is what defines the safety and quality of an e-juice. E-juice flavorings must be food-grade in quality, however this does not necessarily mean there has been adequate research into their safety when inhaled over extended periods of time.

Research has shown potentially harmful effects of compounds found in some e-juice flavourings. Although there is no conclusive evidence yet, compounds on our watch list to avoid include diacetyl (popcorn flavour – now rarely used) [1], cinnamaldehyde (cinnamon flavour) [2] and hexyl acetate (sweet apple flavour) [3].

Which e-juice flavoring(s) you choose to go for is a personal choice.

Generally, the quality of flavor of an e-juice will dictate how expensive it is – more complex, or handmade flavours will cost more than simpler ones. This is the basis of ‘premium’ and ‘regular’ e-juices, discussed in a later section.

Some people think cheaper e-juice flavorings are less satisfying – it is individual choice however, and they are great if you are new to vaping and trying to find a flavor you like.

Nicotine Content of E-juice

Nicotine side effects

You can select the nicotine content of your e-juice. Different providers will have different strength e-juices, generally within these ranges:

  • Nicotine free: 0 mg/ml
  • Low nicotine: 3 – 8 mg/ml
  • Medium nicotine: 10 – 15 mg/ml
  • High nicotine: 16 – 18 mg/ml
  • Extra high nicotine: 24 – 42 mg/ml

If a concentration you have purchased is too high when ask what’s in vape juice, it is possible to dilute it with nicotine-free e-juice of the same flavour. These nicotine concentrations can also be marketed as a percentage, for example 12 mg/ml nicotine e-juice can be described as 1.2% nicotine.

Regular Vs. Premium E-juices

The Difference Between The Two

Regular Vs. Premium E-juices

Premium e-juices often come in glass bottles with stylish branding

E-juices come in two categories: regular and premium. Premium e-juices are more expensive than regular ones, and it the flavourings and packaging that define e-juices as regular or premium. Regular e-juice does not mean dangerous e-juice; trusted sellers will often offer both. Regardless of regular or premium, all ingredients in an e-liquid should be safe for human consumption. But, as discussed earlier, this does not necessarily mean safe for inhalation.

On Flavor

It can be entirely up to a vendor whether they want to market an e-juice as premium or not. Flavour in juice is entirely personal preference, and you might be very happy with regular e-juice. One thing to remember is that regular and premium e-juice providers alike still do not need to put the ingredients they use on their product descriptions.

Premium E-juices

In premium e-juices, you can expect an overall product of higher quality. Quality controls should be in place to ensure the nicotine content is what it says on the label, the diacetyl content will be displayed on the bottle, and they will generally be diacetyl free. You can also sometimes choose how strong you would like the flavour, and the ratio of PG/VG.

Some vendors label their e-juices as premium as they create and blend the flavours themselves which increases the price. They will also generally come in more attractive packaging, for example, glass bottles rather than plastic. Another thing that can make an e-juice premium is the act of ‘steeping’ – a process that removes any volatile liquids from the e-juice, making it smoother to inhale.

What Makes E-Juice Premium

  • they create and blend the flavours themselves
  • generally come in more attractive packaging
  • the act of ‘steeping’ – a process that removes any volatile liquids from the e-juice

Regular E-juices

Regular e-juices are generally mass-produced in a cheaper fashion. Regular e-juices are associated with fewer quality controls, but some people deem these extra quality controls unnecessary, as trusted regular e-juices will be produced in highly controlled environments.

You are more likely to buy poor quality, or dangerous e-juice if it is very cheap and not from a trusted seller. Some ‘regular’ e-juices have been found to contain chemicals that might be dangerous for human consumption. However, regular e-juices from trusted sellers are good quality and safe, it might just be that the flavours are a little more basic.

Here’s a Table to Further Understands The Two Categories of E-Juice

Regular E-Juices Premium E-Juices
mass-produced more expensive
cheaper fashion higher quality
fewer quality controls more attractive packaging
more likely to buy poor quality the act of ‘steeping’

Choosing An E-Juice


One thing to consider when choosing an e-juice is to make sure that it suits what you need. Do not forget also your goal to have a better experience in using a vape.

The things to remember when selecting e-juice is the flavor, your will to quit smoking because this can be a nicotine substitute, and your goal of producing great vapor.

Is Vape Juice Can Make You Cough?


There’s an occasion that a person will experience cough because of e-liquid. It might be his first time to start using a vaporizer. Another reason why there is a coughing situation is that, the vape setting is in high mode and the percentage of high nicotine in e-liquid could be the reason of the coughing sensation.


In this article, we’ve summarised all you need to know about e-juice and what is in vape juice. We hope you can use this information to make your decision about e-juice flavour, PG/VG ratios, premium or regular quality, and nicotine concentration.

Most importantly, do your research on your e-juice flavourings, and try to keep it diacetyl-free if you want to avoid small, but potential, health risks.


Refer to these sources for this article

1. Centers for Disease Control and Prevention (2002). Fixed obstructive lung disease in workers at a microwave popcorn factory (7th ed.). [accessed 20/10/18]

2. Identification of toxicants in cinnamon-flavored electronic cigarette refill fluids. Behar RZ, Davis B, Wang Y, Bahl V, Lin S, Talbot P. Toxicol In Vitro. 2014 Mar; 28(2):198-208.

3. Kim, Shin Ae et al. “Cariogenic Potential of Sweet Flavors in Electronic-Cigarette Liquids.” Ed. Neal Doran. PLoS ONE 13.9 (2018): e0203717. PMC. Web. [accessed 18 Oct. 2018]

Dr. Annie Macpherson
Dr. Annie Macpherson

Annie has a PhD in Genome Stability from the University of Sussex. She has first-hand experience in cancer and human disease research. This allows her to provide us with new and unbiased insights into the ongoing research of the public and health effects of vaping. She loves an adventure, and has travelled through South East Asia and Australia working for Vaping Insider.