Squalene is a naturally occurring lipid found in human sebum, used in skincare as an emollient and skin-conditioning agent that helps reduce transepidermal water loss. In cosmetics it is often hydrogenated to the more stable form squalane, as raw squalene oxidizes readily.
| Reported effect | How often | Notes |
|---|---|---|
| Comedogenic reaction / clogged pores | Uncommon | Oxidized squalene has been linked to comedone formation in acne-prone skin. |
| Skin irritation or redness | Rare | Generally well tolerated; mild irritation reported infrequently. |
| Allergic contact dermatitis | Very rare | Isolated case reports; squalene is considered low-sensitizing. |
| Oxidative breakdown causing skin reactivity | Uncommon | Squalene is prone to peroxidation, and oxidation products may be irritating or pro-inflammatory. |
Frequencies reflect typical cosmetic use reported in the literature, not a guarantee for your skin.