When it comes to e-liquid, two terms constantly crop up: VG and PG. This can seem confusing to the newcomer, but knowledge of these two ingredients can vastly improve your vaping experience. Here’s our easy-to-follow guide on everything you need to know about VG and PG.
What are PG and VG?
Propylene Glycol (PG) and Vegetable Glycerine (VG) form the base of all e-liquids and affect the liquid’s thickness, flavour intensity, throat-hit and vapour production.
Different e-liquids have different PG/VG ratios. The PG/VG ratio you need will be determined by your device and coil setup, as well as your personal preference.
VG is a derivative of vegetable oil and is used to thicken the consistency of e-liquid. This then creates dense vapour clouds that many people who partake in sub-ohm vaping enjoy.
PG is propylene glycol and has a thin consistency. This is the component that often provides the bigger throat hit and is closely linked to the sensation of smoking. It is also sometimes used to carry flavour in food products. You can learn about these different elements, as well as the best PG VG ratio below.
PG is a synthetic liquid with a consistency slightly thicker than water. The PG used in your e-liquid is manufactured on an industrial scale by the reaction of propylene oxide with water. This process produces PG of very high purity, known as pharmaceutical grade. PG is a colourless liquid, with practically no taste or odour. It’s part of the chemical family known as “diols”, and the chemical structure is similar to an alcohol you might be familiar with, ethanol; found in alcoholic drinks. If you can think back to your school days you might remember from chemistry that “like dissolves like”, meaning PG is readily soluble in water as they share similar chemical properties.
Propylene Glycol is a colourless and odourless synthetic liquid used as a base for e-liquid.
PG produces a much stronger ‘throat-hit’ than VG, mimicking the sensation of smoking. Due to this, you will rarely see an e-liquid with a higher PG ratio of 70% as the vape becomes too harsh.
It has a thinner consistency than VG.
It is often considered a ‘flavour carrier’, as its presence helps boost the flavours added to it.
PG is a common ingredient in many foods and products that you use daily, such as toothpaste, soft drinks, bread and dairy products where it is used as an antioxidant, moisture preserver and stabilizer. It is also used in fog machines to create artificial stage smoke.
Propylene Glycol can be found in various common household items. Amongst others, these include:
Nicotine inhalers
Toothpaste and other oral hygiene products
Medical products used orally, injected or as topical formulations
Pet food (excluding cat food)
Beauty products, including make-up, shampoo and baby wipes
What are the effects of PG in Vape Juice?
PG is used in vape juice to give more of a throat hit, making it a more popular choice with those who are trying to quit using cigarettes. It also thins out the liquid, making for more moderate, and even subtle plumes of vapour. If a person trying to quit smoking were looking for the best PG VG ratio, they would likely go for something higher in PG to give them the experience closest to smoking.
How else is PG Used?
Propylene glycol is used in a range of oral and topical medicines. It can also be used as a drug stabilizer and solvent.
Can you be allergic to PG or VG?
Allergies to PG and VG are extremely rare, and only 1 in 1000 people suffer from some kind of intolerance. Even if an allergy is present, the symptoms are often so minuscule that the person does not even notice them.
Is it safe?
Studies have shown that PG is safe to ingest orally, and the FDA has deemed it “generally recognized as safe” to be used as a food additive. However, most studies into the safety of propylene glycol look at ingestion, rather than consuming it in aerosol form. Of the limited studies that exist, a long-term experiment held in 1947 judged that inhaling PG was ‘completely harmless’. A 2010 study looking at PGEs (a mixture of propylene glycol and glycol ethers) suggested an increased risk of developing respiratory and immune disorders in children, such as asthma, hay fever and eczema. However, it was judged that glycol ethers, and not PG, are the more likely cause. Looking at the evidence, it is sensible to assume that PG is safe to be inhaled, but there is a need for more comprehensive studies to confirm this. Many misinformed scaremongering stories in the media claim that PG is a toxic substance used in antifreeze. However, there are two types of antifreeze: toxic and “non-toxic”. The toxic antifreeze uses the dangerous substance referred to as ethylene glycol, which is not used in vaping. PG-based antifreeze is used in food-processing machinery where toxic antifreeze could be problematic.
While PG is regarded as safe for humans and is generally regarded as safe as a food additive for dogs, it has been linked to Heinz body anemia in cats. Be careful when vaping around cats, particularly if you use PG in your e-liquid.
VG is vegetable glycerin, a derivative of vegetable oil. This ingredient is used mostly for thickening an e-liquid and therefore creating more dense vapour clouds. This makes a higher VG liquid better for those who enjoy sub-ohm vapour and like to ‘throw clouds.’ VG also has a slightly sweeter taste, so it can be good for the flavour of an e-liquid. In terms of the ratios of PG and VG, you’ll likely find that an e-liquid higher in VG is a sweeter flavour, such as a dessert flavour or bubblegum flavour.
Vegetable Glycerine is a colourless and odourless natural, syrup-like liquid extracted from vegetable oils.
VG produces more vapour than PG and has a smoother ‘throat-hit’, making it ideal for ‘cloud-chasing’ with a sub-ohm device.
It has a thicker consistency than PG. Due to this, you will rarely see an e-liquid with a higher VG ratio of 80% as the liquid becomes extremely thick and clogs up coils.
VG has a slightly sweet taste which can have a small effect on the overall taste of the e-liquid.
VG is commonly found in food, cosmetic and pharmaceutical products, as it provides several benefits. For example, VG provides a sweet taste and can stop ice crystals from forming in frozen foods such as ice cream.
The FDA has classified vegetable glycerine as “generally recognised as safe”.
What is it used for?
Again, it can be found in numerous medical, food and personal care products:
Sweetener as sugar replacement
Beauty products, such as make-up, mousse, bubble bath, aftershave, and deodorant
Pet food
Soap and hand cream
Food such as baked goods, to increase moisture
To provide a thickening agent for certain medicinal creams, capsule pills, and jellies
Toothpaste and other dental care products
What are the effects of VG in e-liquid?
The main effects of VG in an e-liquid are the sweet flavour and the huge clouds that the person vaping can enjoy when using it. Of course, the PG VG ratio must still be correct, but the best PG VG ratio will all depend on that person’s preferences. Generally, if you’re somebody who enjoys thick, luscious clouds while vaping, a higher VG liquid will likely be your best bet. In some cases, you can vape a liquid that is 100% VG safely due to its thickness. However, this may need to be a E-liquid juice, as many vape stores offer a mixture of PG and VG only.
How else is VG used?
Vegetable glycerin is not only used in e-liquids, but in cosmetics, pharmaceuticals, and foods.
Is it safe?
The FDA has classified VG as “generally recognised as safe” and it is widely regarded as one of the most benign substances known to man. The SIDS assessment profile show it to have low toxicity when consumed, and of low potential to irritate the skin or eye. This, along with the widespread use of VG in food and medicine suggest it is safe for humans. However, as with PG, there are limited studies on VG being inhaled as opposed to ingestion. A 2008 study of the toxicity of inhaling aerosolized glycerol found minimal risks. We can assume the use of VG in vaping has no serious impact on health but, as with PG, we would welcome more detailed studies.
It is important to note that the risk of being allergic to vegetable glycerin is very low, making it a useful alternative for people who have issues when vaping e-juice containing PG. If you are allergic to palm oil or coconut oil then VG could prove a problem, but this is relatively uncommon. Diabetics could possibly experience problems with metabolizing VG, but this would not be an issue at the levels used in vaping.
Understanding Ratios PG and VG for E- Liquid
Many people enjoy making their own vape juice, in which case, understanding the ideal PG VG ratio is crucial. This is the only way to ensure your e-liquid provides the vaping experience you are looking for. If you’re looking to make your own vape juice it may be worth getting an E Liquid.
Below, we have PG and VG ratios that you can use as a starting point. You can test each one until you find your perfect mix.
Best Ratios PG and VG
50 VG / 50 PG
This is equal parts PG and VG. This is often found in cheaper, more basic flavours. Clouds will be mild, and the experience will provide a good throat hit for those who feel they need it.
60 VG / 40 PG
This ratio will give less of a throat hit, with moderate clouds of vapour. It’s popular with those who still enjoy a slight throat hit but enjoy the experience of vaping for the thick vapour clouds.
70 VG / 30 PG
This ratio gives a barely noticeable throat hit, with plenty of vapour clouds. Of course, there is the option to go even higher in VG for those who want even bigger clouds or are considering entering competitions.
PG VG Ratio Summary
In short, the more PG in a vape juice, the thinner the liquid and the stronger the throat hit. More VG gives more vapour and a sweeter taste overall. It’s crucial to find the right mix for your needs when mixing your own e-liquid.
What is the best PG/VG ratio for flavour?
There is a reason why many vapers move towards sub-ohm devices as they become more experienced, and that is flavour Although PG is a ‘flavour carrier’, the flavour intensity of higher-PG e-liquids are hindered by the device and coil used. In comparison, sub-ohm devices paired with higher VG e-liquid, produce double the vapour and thus double the flavour E-liquid !
Are PG and VG safe to vape?
Propylene Glycol and Vegetable Glycerine have been consumed by humans for decades. Both are considered safe for human consumption by US, European and UK food authorities. In fact, PG and VG are common ingredients in many foods, cosmetic and pharmaceutical products.
PG can commonly be found in:
Toothpaste
Medical products (oral, topical, rectal, inhalation, injectable and drop (eye, ear, and nose))
Theatrical smoke (stage smoke)
VG can commonly be found in:
Ice cream and other frozen goods
Cakes and other baked goods
Natural sweeteners
When it comes to its safety in e-liquid, it is important to note that e-liquid is tightly regulated, especially here in the UK. The TPD, which came into force in the UK in 2014, requires e-liquid and their ingredients to meet strict safety standards and be tested regularly.
Vaping is not considered completely risk free, but the leading health organisations in the UK, including the Royal College of General Practitioners, British Medical Association and Cancer Research UK agree that vaping is far less harmful than smoking. Based on the currently available evidence, Public Health England and the Royal College of Physicians estimate they are at least 95% less harmful than traditional combustible cigarettes.
Conclusion
Propylene Glycol (PG) and Vegetable Glycerine (VG) form the base of the e-liquid, to which flavour and nicotine are added.
E-liquid contains a mixture of both PG and VG, with the ratio stated on the bottle.
The PG/VG ratio you need depends on your personal preference and the coil resistance used.
Higher VG liquids work better with lower resistance coils (less than 1ohm), whilst 50/50 e-liquids work well with higher resistance coils (more than 1ohm).
High VG e-liquids produce more vapour and have a smoother throat-hit, but the liquid is thick and can clog up coils quickly.
E-liquids with more PG give more of a throat-hit and a sharper flavour. The liquid is thinner than VG, making it ideal for use with coils above 1ohm.
VG heavy e-liquids usually have a nicotine strength of 3mg or less, as anything above this becomes too harsh.
50/50 e-liquids come premixed with nicotine up to 18mg.
For more of a traditional smoking sensation, use an MTL device with a coil of above 1ohm, paired with 50/50 e-liquid.
For maximum flavour, use a sub-ohm coil and higher VG liquid. You inhale double the vapour, and thus double the flavour!
It’s up to you whether you prefer to vape with an MTL or a Sub-Ohm device. Check out our Guide to DTL, MTL and Sub-Ohm for more information on this!