Body · Cleansing · Sub-chapter 02
A thin, slightly acidic surface film does a quiet job keeping your skin feeling comfortable. Here's the cosmetic chemistry behind it — and how to shop around it.
98 how-to's · Updated 2 May 2026 · Avg. 4 min per piece · Edited by Nelly · Beauty & Style Director
Editorial, not medical advice. This is general body cleansing guidance from our editors, not a diagnosis or treatment plan. If you have a skin concern, speak with a licensed dermatologist or doctor.
The acid mantle — a plain-English description
The acid mantle is a thin film on the skin's surface made up of sebum, sweat, and natural moisturising factors. It sits at a slightly acidic pH — roughly 4.5 to 5.5 on most body skin. That mild acidity supports the environment skin's natural microorganisms prefer. When a highly alkaline cleanser disrupts this film repeatedly, it can take hours to re-establish, and skin often signals the disruption as tightness or a rough, tacky surface feel.
pH reference — cleanser ranges
- 4.5–5.5: Closest to skin's natural surface. Usually comfortable for most body skin.
- 5.5–7: Mild-to-neutral. Most skin handles this fine.
- 7–9: Alkaline end. Surface film often needs a few hours to re-establish.
- 9+: High alkaline. Noticeable tightness on most body skin.