When it comes to e-juice, 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.
In simple terms:
Choosing the wrong PG/VG ratio can put first-timers off so be careful to choose the right level for your equipment.
Now let’s take a look at each in more detail.
PG stands for Propylene Glycol, a petroleum by-product. The fluid has no odor or color and is less viscous than VG. In vaping it is used to provide a ‘throat hit’, which some users claim is similar to the sensation experienced when smoking tobacco. It also carries flavor more effectively than VG, making it the most commonly used suspension fluid for flavor concentrates and nicotine.
Propylene Glycol can be found in various common household items. Amongst others, these include:
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 anti-freeze. However, there are two types of anti-freeze: toxic and “non-toxic”. The toxic anti-freeze uses the dangerous substance referred to as ethylene glycol, which is not used in vaping. PG-based anti-freeze is used in food-processing machinery where toxic anti-freeze 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.
Some people find a high level of PG irritating to the throat. True allergies to PG are rare, but have been reported. If you find yourself coming out in a rash or suffering other unpleasant reactions after using PG-based e-fluid, you may have a more common mild sensitivity to PG, and should look at using high-VG juice instead. Many vendors offer this option.
The most common side effects of using e-liquid containing propylene glycol are symptoms of dehydration, like dry mouth, sore throat, and increased thirst. It is advised to drink more water and liquids than usual for the first few weeks of using your e-cigarette. If hydrated properly, these symptoms usually last anywhere from a few days to a week as the body gets used to the propylene glycol. Be aware that any unusual reactions could be side effects from quitting smoking, and not necessarily because of the PG.
VG stands for Vegetable Glycerin. It is a natural chemical, derived from vegetable oils, so is safe for vegetarians. It is commonly used in e-liquid to give a ‘thick’ sensation to vapor. VG has a slightly sweet taste and is considerably thicker than PG. Vegetable Glycerin provides a much smoother throat hit than Propylene Glycol, making it more suitable for sub-ohm vaping. While nicotine and flavorings are commonly suspended in PG, some vendors are offering a VG alternative, to enable 100% VG mixes.
Again, it can be found in numerous medical, food and personal care products:
The FDA has classified VG as “generally recognized 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.
The increased thickness of VG means it can reduce the life of atomizers quicker than PG-based juice. High VG liquids clog up coils more rapidly, and will not work well, if at all, in certain tanks. Older products are especially susceptible, particularly models that use smaller coils such as clearomizers. The Nautilus range and eGo tanks are some of the more well-known tanks that are known to have difficulties dealing with high VG fluid.
As with PG, the most common side effects of vaping high VG e-liquid are those of dehydration: dry mouth, sore throat, and increased thirst. Again, be sure to drink plenty of water and take a break from vaping if necessary.
There isn’t a one-size-fits-all answer to this. It depends on the kind of vaping experience you prefer. Many people use various levels of PG and VG for different purposes:
It isn’t as simple as deciding on a high VG or PG vape juice and hoping for the best. It all comes down to your equipment. If it isn’t suitable for the job, it can lead to unpleasant throat irritation or wicking problems resulting in dry hits.
The best way to find your PG/VG ‘sweet spot’ to experiment by making your own e-juice. It’s surprisingly easy to do, and very cost-effective. You can check this out in more detail in our DIY e-liquid guide, but here are some things to be aware of:
The basics of PG and VG are quite easy to grasp. They both work in different ways, and each has advantages and disadvantages. Our advice is to start with a 50-50 PG to VG ratio then try out various combinations and see which you prefer. Make sure your vaping setup can deal with the different ratios.
Many vapers like to use different levels of PG and VG at different times, and with various devices and flavors. Tobaccos, fruits and beverage flavors often go well with PG, as the sharpness of the PG blends well with the tart or fizz of the flavoring. Similarly, flavors based on cream, custard and yogurt tend to work well with high VG as the thick mouth sensation adds to the dessert-like feel. There are no fixed rules, just follow what your taste buds tell you!
I am getting dizzy when I vape zero nicotine level of e-juice. I quit smoking cigs 45 days ago. I vape Hometown Hero brand. Any suggestions? Thanks.
Congratulations on quitting cigarettes! I can’t imagine how you did it without nicotine, but in any case eliminating the cigarettes is the most important thing. There isn’t any special reason why vaping (especially without nicotine) should make you dizzy, but if you believe that vaping is causing it, stop using the e-liquid you’re using. The dizziness may be unrelated to vaping and have to do with your breathing or other factors. Any time you get dizzy without a known cause you should see a doctor. Please do.
I have been vaping for 6 months now. The last month I have become very tired and achy, muscles and joints. I have had blood tests and they have confirmed that I am Vitamin D deficient and have been put on a course of tablets. I drink and eat lots of dairy products and am always outside when the sun shines, so am confused as to why i have this deficiency. Has anyone else had this problem since vaping? Would appreciate any feedback you can give. Thank you.
I have been experiencing the same thing!
I have been vaping for pass 6 years, mostly over the counter stuff like logic.
I’m in a lot of pain lately; muscles, joints and feeling very tired.
Also diagnosed with low vitamin D.
I read in some other chats that it could be the pg.
I’m trying to not vape as much and looking to change to vg juice only to see if I get better.
If not I may stop vaping all together to see if I stop feeling like I’m 90 years old.
It seems unlikely that the thing you’ve been doing for six years would suddenly cause problems. Those symptoms could be caused by many conditions. I hope you get to the bottom if it.
Hi Lisa, I’ve never heard of such a problem related to vaping, and I can’t imagine what physiological mechanism would tie this to vaping. I think the vaping and the Vitamin D deficiency happening at the same time is just a coincidence.
My Dr just diagnosed me with vitamin D deficiency also?? Something, tired aching muscles and joints…. She ran blood test for R.A. and Lupus and they came back negative. Kind of makes me wonder if that may have something to do with it.. Been vaping for 2 years now.
There are about 40 million vapers worldwide. I’m sure the same percentage of them as in the general population have vitamin D deficiencies. I can’t imagine how vaping could cause a vitamin deficiency.
Hey Jim, I was interested if you could help someone like me who really wants to start vaping, but hasn’t smoked cigs in 6 years. I really enjoy the mouthfeel of vaping and the sort of having something in hand which i can enjoy at times. I am also on the other hand kinda scared of the health risks vaping brings with itself. Is there any chance you could inform me what kinda chemicals i should try to keep away from and which of PG/VG is less unhealthy for you, even better would be if you already have a product… Read more »
I’m not sure how to respond to this. I consider the risks of vaping with normal commercial e-liquid very slight, but since you apparently disagree, why do it? If you’re concerned about health risks from vaping, and you haven’t smoked in six years (so clearly don’t need to vape to avoid cigarettes), I’m not sure why you would want to start vaping. That said, what risks there are, assuming you’re not pregnant and don’t have heart disease, lie in the carrier liquids, not in nicotine. So vape as little as you need to if you’re trying to avoid the unknown… Read more »
Thanks for replying Jim. Really hope it has nothing to do with it. I’ll take the tablets and carry on vaping because there’s no way I’m going back to smoking.
Hi guys. I’ve been vaping for about 6 years and have tried a lot of different brands of juice. I only vape menthol. Whenever I find a brand I like, invariably it becomes difficult to obtain after a while. My latest brand is ridiculously hard to come by so I’ve decided to delve into the world of mixing my own. The juice I always use is 50/50 menthol. I can buy 1 litre of ready mixed 50/50 juice and 100mls of menthol concentrate for next to nothing. Am I right in thinking that for my needs, just combining the whole… Read more »
Hi Ian, If you vape on nicotine-free e-liquid then this does sound like a good idea. Here’s a couple of things to consider: 1. Mixing a 50/50 base with a PG based flavor concentrate will result in a juice that has more than 50% PG. If you want a 50/50 end result you will need to use a higher VG base, or add a bit of VG to the mix. 2. Make sure you check the recommended mixing percentage of your concentrate. Depending on the potency of the flavor, it can be from as low as 0.1% to as high… Read more »
I used the vanilla that V2 had which is no longer available. Most of the ones I’ve tried since are very thick and sweet. I don’t like it sweet so if I order, do I need to be higher pg vs vg. I’ve tried a few 50/50 and they are still very thick and sweet.
why are some e-juices bottle doesn’t show how many pg / vg ?
I’m not sure why. The manufacturer usually provides that information, although it’s not required by law.