Squalane vs squalene: the one-letter difference explained

One letter, six double bonds

The names differ by one letter and the molecules by twelve hydrogen atoms. Squalene, C30H50, is a branched 30-carbon chain with six double bonds; squalane, C30H62, is the same chain with none.¹² CosIng's chemical names say the same: squalene is a hexamethyltetracosa-hexaene, squalane a hexamethyltetracosane.³⁴ In short, squalane is the saturated derivative of squalene.⁵

The step between them is hydrogenation, adding hydrogen across the double bonds. A 2025 study of squalane production describes the catalytic hydrogenation of squalene to squalane as one of the molecule's key transformations.⁶

Where each one comes from

Squalene takes its name from sharks (Squalus): it was first isolated from shark liver oil, its richest source.⁷ A 2024 review reports that shark liver oil has been the main commercial source since the molecule's discovery and is still the least expensive, and links the killing of three to six million deep-sea sharks a year to demand for squalene.⁸

Plant oils contain it in smaller amounts. Olive oil, at about 564 mg per 100 g, is the main plant source, and squalene can also be recovered from olive pomace.⁶ Amaranth, rice bran, palm and wheat-germ oil are others.⁷ In people, squalene makes up about 13% of sebum, the oil the skin produces.⁷

Squalane from sugarcane is made another way. Sugar cane is fermented by genetically modified yeast to produce a smaller molecule, trans-beta-farnesene, which is joined in pairs and hydrogenated to give squalane.⁶ Microorganisms engineered to make squalene itself are also being developed as an alternative to sharks.⁸

CosIng has a single entry for each name, and describes squalene as found in fish and plant oils, so the name alone does not reveal the source.³⁴ Its entries for Squalene and Hydrogenated Squalene also carry a reminder to consider Annex II, entry 419 of the EU regulation, which bans Category 1 and Category 2 animal by-product material and ingredients derived from it.³⁹¹⁰

Why squalene is hydrogenated

Squalene's unsaturation makes it susceptible to oxidation,⁸ and the 2025 study calls it very unstable and easily oxidised.⁶ On the skin it appears to act as an antioxidant by quenching singlet oxygen, and sunlight converts it into squalene monohydroperoxide, its primary oxidation product.⁷

Hydrogenation removes the double bonds. The same study notes that squalane is widely used in cosmetics for its emollient and moisturising properties, and gives a specification for cosmetic use: over 92% purity and an iodine value, a measure of the double bonds left, below 1.00.⁶

What reviewers concluded

The US Cosmetic Ingredient Review panel first assessed both in 1982. It found their acute toxicity in animals low, both non-irritating to rabbit skin and eyes at 100%, and squalene not a significant skin irritant or sensitiser in the formulations tested in people.¹¹ In 2023 it reviewed newer studies and confirmed that squalane and squalene are safe as cosmetic ingredients in the practices of use and concentration it describes.¹² Neither has an entry in the EU annexes.¹⁰

How to tell them apart on a label

• Read the vowel before the final n. Squalane, with an a, is the saturated form; Squalene, with an e, is not.
• Hydrogenated Squalene is a separate name, which CosIng describes as the end-product of the controlled hydrogenation of squalene.⁹
• The list does not name the source. Shark, olive, sugarcane or microbial material goes by the same INCI name; only the brand can say which it used.
• See it in context with the ingredient checker, which shows what each name in a list does. How to read a cosmetic ingredient list covers the rest of the label.