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Sodium Hydroxide

What Sodium Hydroxide is & what it does

A strong alkali used in tiny amounts to raise and balance a formula's pH and to neutralize acidic thickeners into gels. It has no direct skin benefit but is key to a stable, skin-friendly product.

What is Sodium Hydroxide doing in my skincare?

Sodium hydroxide (lye) is used in tiny amounts purely as a pH adjuster: it neutralises acids so the finished formula sits at a skin-friendly pH. None of the raw lye remains active in the final product.

Is Sodium Hydroxide safe in cosmetics?

Yes. Although concentrated lye is caustic, in finished products it is used at minute, fully-neutralised levels that are safe and non-irritating. It is a standard, well-reviewed pH adjuster.

Is Sodium Hydroxide natural?

No, it is synthetic (lye, made by electrolysis of salt water). It is used in tiny, fully-neutralised amounts only to adjust pH, so none of the raw, caustic material remains active in the finished product.

Is Sodium Hydroxide safe to use during pregnancy?

Sodium hydroxide has no pregnancy concern in finished products. It is used in tiny, fully-neutralised amounts only to adjust pH, so none of the raw material remains active.

Sunscreens with Sodium Hydroxide

We rate 1532 sunscreens that contain it, showing the top 10 by overall score:

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