By ingredient · Sub-chapter 01
Sulphates and silicones. Two ingredients that have been argued over in every forum, comment section, and beauty aisle for twenty years. Here is the evidence, both sides.
118 how-to's · Updated 1 May 2026 · Avg. 5 min per piece · Edited by Nelly · Beauty & Style Director
Editor's note
Sulphates and silicones became villains at roughly the same time — around the mid-2000s, when the natural beauty movement found its first viral talking points. Both fell from grace without a rigorous trial. Neither is as simple as its detractors suggest, nor as harmless as its defenders claim. What they share: they do different things to different hair, and the hair on your head is the only evidence that matters.
Sulphates
Sulphates — primarily sodium lauryl sulphate (SLS) and sodium laureth sulphate (SLES) — are surfactants that lower surface tension between water and oil, allowing sebum, product residue, and environmental grime to rinse away. They are effective, inexpensive, and have been in shampoos since the 1930s. The debate centres on whether they are too effective — stripping natural oils alongside dirt. Fine hair and oily scalps often do better with sulphates than without. Curly, dry, and colour-treated hair generally benefits from sulphate-free alternatives, provided the alternative surfactant is genuinely mild.
Silicones
Silicones coat the hair shaft, reduce friction between strands, add slip to detangling, and create a smoothed-cuticle appearance. They do not penetrate the cortex: their action is entirely surface-level. The main concern is buildup — silicones require a proper surfactant to clear, meaning sulphate-free routines with silicone-heavy products create an accumulation problem over time. The solution is either to use a clarifying sulphate shampoo periodically, or to switch to silicone-free products in a sulphate-free routine. The two ingredients are functionally linked.
Other ingredients sub-chapters
Everything we've published on sulphates and silicones
- Sulphate-free shampoo: who it's actually for
- SLS vs SLES: the difference that matters
- Dimethicone in conditioners — clearing the buildup
- Amodimethicone: the silicone that's actually targeted
- The sulphate–silicone dependency explained
- Clarifying once a month — is it enough?