What is it?
A natural mixture of phospholipids, the fat-like molecules that make up cell membranes, such as phosphatidylcholine, along with some oil. Most lecithin comes from soybean oil; it is also made from sunflower, rapeseed and other seed oils, and from egg yolk. In cosmetics it works as an emulsifier and skin-conditioning ingredient and can form liposomes. It is also a common food additive (E 322).
Key information
- Lecithin is not ethoxylated; it is separated from crude vegetable oil by adding water, which makes the phospholipids drop out as a gum.
- The CIR Expert Panel concluded in 2015 that lecithin is safe as used, dropping an earlier 15 percent limit for leave-on products.
- Soy and egg lecithins can carry traces of protein from their source, and rare allergic reactions have been reported.
- EFSA found no need for a numerical acceptable daily intake for lecithins as food additives.
More information
Most lecithin is a by-product of refining vegetable oil. In a step called degumming, water is added to crude oil and the mixture is heated; the phospholipids take up water, no longer dissolve in the oil and are separated by centrifuge. The gum may then be dried, bleached or refined further, for example with acetone to make oil-free powders. Soy lecithin is usually made from soybean oil extracted with hexane; the reviews we consulted do not report hexane residues in finished lecithin.
The Cosmetic Ingredient Review (CIR) Expert Panel first reviewed lecithin in 2001 and limited leave-on products to 15 percent, the highest level tested in people. In its 2015 assessment of lecithin and 16 related phospholipids, including hydrogenated lecithin, the Panel concluded they are safe as used. It dropped the 15 percent limit, noting that human tests at that level for irritation, sensitization and photosensitization were all negative and that extensive clinical experience showed no problems, and dropped a caution about nitrosamine formation, which it found rested on experimental conditions that do not reflect cosmetic use.
Soy and egg lecithins can carry small amounts of protein, which is what triggers food allergies. EFSA noted case reports of hypersensitivity linked to soy and egg lecithins, attributed them to residual proteins, and said protein content should be kept as low as possible. A study reviewed by the CIR found only 2.8 mg of protein per 100 g of soy lecithin and concluded that these proteins have little antigenicity for people with soybean allergy.
In U.S. foods, lecithin from soy must be labeled as soy. In cosmetics the ingredient name is simply “lecithin,” whatever the source, so people with a soy or egg allergy may want products that name the source, such as sunflower lecithin.
Sources: Cosmetic Ingredient Review: Safety assessment of lecithin and other phosphoglycerides as used in cosmetics (2015); EFSA: Re-evaluation of lecithins (E 322) as a food additive (2017)
