Propylene Glycol vs. Vegetable Glycerin E-Liquid – What’s the Difference?

posted Oct 23 2013 10:14 AM

If you’re a smoker looking to make the switch to electronic cigarettes, you’re probably curious about what you’ll be putting into your lungs instead of that dreadful tobacco smoke. Unfortunately, vaping terminology can be a bit confusing at first, so in this article I’m going to try and explain the differences between the two most widely used e-liquid bases: propylene glycol (PG) and vegetable glycerin (VG).

E-liquids contain four ingredients: a PG or VG base, nicotine, water and flavorings. The base, or carrier, holds the nicotine and flavor in suspension so your e-cigarette can produce those nice clouds of smoke-like vapor. Both propylene glycol and vegetable glycerin are non-toxic organic compounds and generally considered safe for consumption. In fact, they are widely used as food additives in a variety of commercially available products.

First, let’s talk about PG-based e-liquid, because it’s the most popular of the two. Due to the fact that propylene glycol is relatively thin in consistency, this kind of e-liquid is runnier than the VG variety, and is more easily absorbed by the polyfill fabric inside the cartomizer. The low density of the juice also means that gunk doesn’t build up on the heating element of your e-cigarette as fast as it does when thicker vegetable glycerin liquid is used. Propylene glycol is a tasteless odorless substance, so it doesn’t alter the flavor of the e-liquid in any way. It’s also a powerful humectant, so while it will dry your mouth and throat if used consistently, PG also produces a stronger throat hit, similar to that of tobacco cigarettes. On the down side, propylene glycol is known to cause allergic reactions in some e-cig users. These can vary from minor reactions, like a tingling sensation in the throat, to serious irritations on various parts of the body. If you experience any unusual symptoms after vaping PG e-liquid, it’s best to stop using it immediately and switch to vegetable glycerin.

Vegetable glycerin is a considerably thicker solution, compared to propylene glycol. On its own, VG has a slight sweet taste which also makes the e-liquid sweeter and the flavors are a little difficult to detect. While PG is known to give users a dry mouth, some vapers have complained about phlegm building up in their throat after using vegetable glycerin-based juices. You also get less of a throat hit when using VG. On the upside, because of its high consistency, VG e-liquids produce significantly more vapor and don’t cause allergic reactions or irritations as often as propylene glycol.

It’s fair to say the vaping community is evenly divided when it comes to e-liquid preference. Some enjoy the smoking-like throat hit of vaping propylene glycol juices, while others prefer the thick plumes of vapor and the sweet taste of vegetable glycerin. It’s hard to say which one of the two is the best, because it ultimately comes down to personal preference. I’d suggest you start with a PG e-liquid, especially if you’re looking for an experience close to smoking, and try out a VG juice along the way, just to see what you’re missing out on. To get the best of both worlds, many vapers prefer a PG/VG mix, in different amounts.  This way, they get a decent throat hit as well as pillowy clouds of thick vapor.