Regardless of the flavour, style, or brand all e-juice consists of a mix of Vegetable Glycerin (VG) and Propylene Glycol (PG). Both these ingredients make up the bulk of a standard bottle of e-juice and work in tandem to provide a throat hit, carry flavour, and produce vapour. Each ingredient plays an important role in any e-liquid, and while the properties of both can seem confusing to new vapers, knowledge of the two will greatly improve your vaping experience.
What exactly is PG and VG?
- PG and VG are both odourless liquids that are combined to create the base of all e-liquids
- Both ingredients technically belong to the alcohol chemical class, despite the fact that they are in no way intoxicating. Within this chemical class they are deemed as “sugar alcohols” which are included in many consumable products.
- They each produce vapour when heated, allowing for inhalation
- The two liquids have different consistencies to one another and a slightly different taste
- Both have distinct mouth and throat sensations when vaped
- Their ratio in an e-liquid can change how the final product will vape
- Some set-ups work better with certain levels of PG and VG
Now that the similarities and uses of the two ingredients has been established, we’ll go more in depth into both PG and VG so you know more about how the substances affect your e-liquid.
What is PG?
Also known as PG, this substance is a petroleum by-product that is often used in liquid sweeteners, ice cream, whipped dairy products, soda, and pharmaceutical vaporizers. Within the world of e-cigarettes and vape juice, PG is generally used to provide a “throat hit,” which many users claim is similar to the sensation experienced when smoking a cigarette. PG is also a flavour carrier, making it the primary ingredient for suspending flavour in e-liquids.
How is it used?
While the liquid is now more commonly seen in e-liquids, PG is actually used in a wide variety of household items, some of which include:
- Nicotine inhalers
- Toothpaste and various other oral hygiene products
- Medical products that are administered orally, injected, or as topical formulations
- Pet food (excluding cat food)
- Various beauty products, including make-up, shampoo, and baby wipes
Is it safe to consume?
To answer simply, yes, PG is safe to ingest orally. The FDA has deemed the substance “generally recognized as safe” to be used as a food additive. However, the majority of the studies on PG look at ingestion of the liquid, rather than consuming it in an inhalable format. That being said, there are some limited studies on the inhalation of PG, including a 1947 experiment that judged inhaling PG as “completely harmless.”
It should be noted, a 2010 study looking at PGEs (a mix of propylene glycol and glycol ethers) suggested the substance could cause an increased risk of developing respiratory and immune disorders in children. These disorders include hay fever, asthma, and eczema, but it was judged later that glycol ethers, and not PG, were the likely cause of these disorders. Looking at that, it is then sensible to assume that PG is safe to be inhaled, though more dedicated research with comprehensive results still need to be done to confirm this.
While PG is generally recognized as safe for human consumption, many media outlets continue to push misinformation and fear mongering about e-cigarettes and e-liquids. One of the most common pieces of misinformation spread about e-liquids is the presence of PG in antifreeze. While it is somewhat true, there are two types of antifreeze: toxic and “non-toxic,” the later is the only one that contains PG, while the former uses a dangerous substance known as ethylene glycol. PG-based antifreeze is in fact manufactured in food-processing machinery and is kept far from toxic antifreeze.
Should I be aware of anything when vaping PG?
While the majority of vapers should be able to inhale PG without any negative side effects, some people find that a high level of PG can be irritating to the throat. True allergies to PG are quite rare, though some have been reported, and will most likely manifest as a rash or some other sort of unpleasantness after using a mostly PG-based e-liquid. Thankfully, many companies and manufacturers do produce high VG vape juices as an option.
Even without an allergy, there are some reactions people may have to PG, including dry mouth, sore throats, and increased thirst. To combat these side effects, be sure to drink plenty of water during or after vaping. These symptoms are more common in new vapers and will usually subside in a few days to a week as the body gets use to PG. Be aware that some of these reactions can also occur if you are quitting smoking and not necessarily because of the PG.
What is VG?
Known more commonly as VG, this natural chemical is derived from vegetable oils and is commonly used by the food industry as a sweetener. Within vaping, VG is primarily used to give a viscous nature to an e-liquid, while also providing a sweetness, smooth throat hit, and the majority of the vapour produced. High VG juices are generally reserved for people using rebuildable dripping atomizers and sub-ohm tanks. People with PG allergies may also want to look at 100% VG mixes as an alternative to conventional e-liquids.
How is it used?
As we mentioned earlier, VG is commonly used in the food industry, though it also appears in numerous medical and personal care products. The products include:
- Sweeteners and sugar replacements
- Various beauty products, such as make-up, bubble bath, aftershave, mousse, and deodorant
- Ped food
- Soap and hand cream
- Baked goods, to increase moisture
- Certain medical creams, capsule pills, and jellies
- Toothpaste and various dental care products
Is it safe to consume?
As with PG, VG is recognized by the FDA as “safe” and is often regarded as one of the most benign substances known to man. According to the SIDS assessment profile for VG, the substance is shown to have a low toxicity when consumed, as well as having a low potential to irritate the skin or eye upon contact. However, like PG, studies on the inhalation of VG is relatively sparse and more research is still needed to provide concrete results.
It is important to note that only a very small minority of people are at risk of being allergic to VG, making it a perfect alternative to people who have issues vaping e-juice with PG in them. Those that have an allergy to palm oil or coconut oil may also be allergic to VG, but this is relatively uncommon and should not affect the majority of vapers. Diabetics may also have some issues metabolizing high amounts of VG, but this would not be an issue at the levels a normal person vapes.
Should I be aware of anything when vaping VG?
Besides the possible allergies and medical issues mentioned above, the only real downside of vaping VG-based e-liquids is the damage it can cause to your coil or atomizer. Simply put, VG has a tendency to clog up coils rapidly, and will not work well, or at all, with certain tanks. These devices are generally older and won’t work with high VG e-juices because of their smaller coils and lack of adequate airflow.
As with PG, the most common side effects of vaping high VG e-juices are dehydration, dry mouth, sore throat, and increased thirst.
What should my PG/VG ratios be?
If you were hoping for a one-size-fits-all answer, I’m sorry, but it really depends on the vaping experience you prefer. We can however shed some light into what the various levels of PG and VG can do and how they’ll affect your vaping experience.
- Throat Hit – Many ex-smokers often crave a distinct hit from their vape and those looking for this kind of experience will want to try an e-liquid with higher amounts of PG. The combination of PG and nicotine will definitely provide a solid throat hit, and higher PG juices may also have better flavour as the ingredient serves as the main flavour carrier in e-liquids.
- Smoothness – High VG e-liquids tend to provide a much more relaxed and smoother throat hit, while also providing a “thicker” mouthfeel. High VG juices will have a bit of a more muted flavour, but this can be remedied by using more power. Remember when increasing the power to stay within the voltage/wattage limits of your atomizer, or you may risk dry hits, damaging your equipment, or burning the coil out.
- Stealth Vaping – While you should only vape in areas where it is allowed, some vapers prefer to have their vaping be a little more lowkey. In this instance, a higher PG e-juice would be best, as it produces a smaller and more discreet cloud.
- Cloudchasing – On the opposite end of the spectrum, cloudchasers are vapers looking to produce a massive plume of vapour that is both dense and long. There are even competitions based around this activity, with the winner being the person who produces the largest cloud. If this interests you, then look towards a high VG e-liquid.
What sort of vape set-up do I need?
While you can easily decide on whether or not you want a high VG or high PG e-liquid, finding the right device to handle these liquids does require a little more thought. Ultimately, you will need a device that can handle whatever e-liquid you want to use in it, and incompatible ones can cause wicking problems, unpleasant throat hits, and dry hits.
- Clearomizers – There was a time when the clearomizer was the most common style of tank for vaping, but in recent times it’s fallen out of favour with most vapers. This style of tank generally takes higher resistance coils and are vaped below 15 watts. Generally speaking, this style of tank is not suitable for high VG e-liquids, as their coils cannot handle thick e-liquids. If you are using a clearomizer, look for an e-liquid that has a decent amount of PG.
- Sub-Ohm Tanks – This style of tank has quickly become the norm in vaping and were primarily built to produce large clouds of vapour. Because of this, these tanks are suited well for high VG e-liquids, as their coils are built and wicked to handle these kinds of liquids.
- Pods – Pod systems are becoming increasingly popular among new and experienced vapers and for good reason. Their compact nature, fuss free experience, and low cost make them ideal as a backup device or for vapers looking for something more discreet and compact. Like clearomizers, pods work best with higher PG e-liquids, specifically 50/50 blends.
- Rebuildables – While not the most convenient of set-ups, vapers who don’t mind putting in a bit of effort will appreciate the flexibility they can get from rebuildable devices. In this case, vapers can use whatever e-juice they prefer, as the simple nature of the devices and their customizability make them capable of using both high VG and high PG e-liquids.
Understanding the differences between VG and PG isn’t something terribly difficult to grasp, however actually putting that knowledge into practice can be a bit of a more daunting task. We would suggest starting out with a 50/50 PG to VG ratio, then branch out into other combinations to see which you prefer. Also, don’t forget to make sure you set-up can handle whatever type of e-liquid you run through it.
Some vapers even like to use different levels of PG and VG at different times to enhance or augment their vaping experience with certain flavours. Tobacco, fruits, and beverages often work well with higher PG e-liquids, as the sharpness provided by the ingredient blends well with tartness, fizz, or flavoring. Similarly, desert, cream, custard, and yogurt based flavours work well with VG as the thick mouth sensation adds to the desert-like feel. That being said, there are no strict rules and you should vape what you enjoy best.