Emulsifier

Emulsifier — an ingredient that allows oil and water to combine into a stable, uniform mixture that would otherwise separate. It works because part of its molecule is attracted to water while another part is attracted to oil, letting it sit at the boundary between the two. Emulsifiers are what give creams and lotions their consistent texture and prevent them from splitting over time.

Key points

• An emulsifier has both water-loving and oil-loving parts, allowing it to bridge oil and water phases.
• It surrounds dispersed droplets to keep them evenly distributed and prevent separation.
• Common cosmetic emulsifiers include lecithin, cetearyl alcohol with related compounds, and various polysorbates.
• The choice of emulsifier influences a product's texture, stability, and overall skin feel.

Frequently asked

Is an emulsifier the same as a surfactant?

Emulsifiers are a type of surfactant, but they are specifically used to stabilize mixtures of oil and water rather than primarily to cleanse or foam.

Are emulsifiers safe for the skin?

Most cosmetic emulsifiers are well tolerated at typical use levels, though some individuals with very sensitive skin may react to certain types.

Related topics

• What Is a Humectant?
• What Is the Skin Barrier?

This is a foundational entry in the SYNC Skin Encyclopedia and is expanded over time. Educational information only — not medical advice.