Lecithin

What it is

Lecithin is the unhydrogenated form of the same phospholipid mixture, extracted from soybean or sunflower seed and consisting mainly of phosphatidylcholine. Its fatty acid tails are still unsaturated, which makes it more skin-softening but also less stable than the hydrogenated version. It works as a mild emulsifier, a wetting agent for powders and pigments, and a carrier for oil-soluble ingredients.

What it does well

• Mild emulsifier that also conditions skin

  Unlike detergent emulsifiers, phospholipids are structurally similar to the skin's own membrane lipids and are well tolerated. Lecithin also helps disperse clays and pigments evenly through a mask base.

  Moderate evidence

Worth knowing

• Prone to oxidising, which affects colour and smell

  Unsaturated lecithin can darken and develop a distinct odour over time, which is why formulators often choose the hydrogenated form for long shelf life. It is a stability rather than a safety issue.

  Matters most toAnyone with an old or heat-exposed product that has changed colour or smell.

Where the EU stands