What’s Actually in E-Liquid? Ingredients and Health Effects

PG is a thin, clear liquid that carries flavour and provides throat hit; VG is a thicker, faintly sweet one that builds vapour. Both are food-grade substances with long histories in pharmaceuticals, food and cosmetics, and both are well tolerated by inhalation in the concentrations vaping uses, with the caveat that a small minority find PG mildly irritating and drift to higher-VG blends.

Their known side effect is mundane: both are humectants, so they dry the mouth, which is why hydration is every vaper’s first advice.

Nicotine is the addictive component and the reason vaping works as a cigarette replacement; it is not the carcinogen in smoking, and UK strengths cap at 20mg/ml. Flavourings are food-grade compounds, which honest observers note were tested historically for eating rather than inhaling: this is where long-term research continues, and where UK rules already ban specific ingredients of concern rather than waiting.

What e-liquid does not contain is the point of comparison: no tar, no carbon monoxide, none of the several thousand combustion products of burning tobacco.