VG stand for Vegetable Glycerin; This is a naturally clear and odorless liquid chemical derived from plant oils, in particular, the oils from the coconut and soy plant. It is one of the most innocuous organic liquids known to man, it’s hypo-allergenic, non-carcinogenic, and non-mutagenic. When it comes to vaping, a lot of ‘non-somethings’ are always a very good thing, only the nicotine should be the compounds getting into your lungs! A study of the toxicity of inhaling aerosolized glycerol found minimal risks, so even if you accidentally ingested VG, it’s not going to cause you any harm.

In everyday life, VG is sometimes used as a food additive, and can also be found in dental hygiene and beauty products. It’s also commonly used as a substitute for alcohol when making botanical extracts. The liquid is sweet and syrupy and produces a lot of vapor when heated. Because of its consistency, many users who have vaped an e-Juice made wholly from, or primarily of VG, have suggested that the vapor tastes slightly sweet. The vape you get is also thick and heavy, but incredibly smooth.

Because of its viscosity, VG-based e-Juices can reduce the life of many an atomizer because the thick, gloopy liquid can clog vape pen coils. High VG e-Juices don’t really work well in clearomizers, and they certainly won’t work in older devices such as the Aspire Nautilus vaporizers, Innokin iClears, and eGo tanks. VG e-Juices also have a much shorter shelf life than products whose bases are made entirely from, or mostly of PG. Around 20 percent of all e-liquids on the market today are VG-based. You can check out the percentage of VG in premium vape juice from eliquid-depot.com.

Propylene Glycol

PG, when it comes to being used in such low levels in e-Juice, is a non-toxic, synthetic chemical compound which, like VG, absorbs water. PG has the ability to replicate the sensations you normally get in your throat from smoking a spliff, so an e-Juice high in PG offers that reassuring feeling of knowing that you’ve actually inhaled something, rather than wondering, “Did I actually take a hit”? Because of this property, PG can make your mouth get quite dry, almost like cotton mouth from a bong.

Interesting Side Note: VG and PG are what’s known as hygroscopic ingredients, they absorb water molecules from the air. When you heat your vape pen, the vapor that is produced actually comes from the water in the chamber. Therefore, the more water soluble a base ingredient, the more vapor it will produce. That’s why an e-Juice with a VG base will produce heaps of vape.

Because PG comes in several ‘grades’, in everyday life it can be used for a whole variety of different reasons. Industrial grade PG products are found in solvents like paints and varnishes, and it’s often used, in high quantities in antifreeze and engine coolants. On the opposite end of the scale, PG is also used in the pharmaceutical company, the most common devices it can be found in are asthma inhalers and nebulizers.

    “Do not be alarmed by the term antifreeze or by the chemical propylene glycol. It is safe at the low concentrations.” – Tonya McKay Becker, polymer scientist.

PG has a bit of an image crisis thanks to information like this, but it’s important to remember that e-Juice contains pharmaceutical grade levels of PG, levels which are much less concentrated, and therefore, less problematic.

Pro-tip: This being said, PG has been known to cause allergic reactions in some users, and on a rare occasion, those who suffer from diabetes have reported an e-Juice made from PG can affect their blood sugar levels. If you find these to be true to you, don’t worry, you can still vape, you’ve just got to use a 100 percent VG based e-Juice.

The reason why propylene glycol is used as the main ingredient in most e-Juices is because it lowers the temperature necessary to vaporize water, and it’s good for carrying flavors. Because of this PG is often used in foods, therefore, The U.S. Food and Drug Administration (FDA) includes PG on its list of substances Generally Recognized as Safe (GRAS), and it meets the requirements of acceptable compounds within Title 21 of the Code of Federal Regulations.

Pro-Tip: There is no such thing as “premium” PG or “premium” VG; it’s all one and the same. If any brand mentions premium, it’s likely they’re talking about the way they flavor their e-Juices. To be considered premium, the flavors should be natural from locally sourced products and extracted organically.