The ones people ask about
Sodium Hydroxide
Sodium hydroxide, also called lye or caustic soda, is a strong alkali made from salt water. Undiluted, it burns.
- On a list as
- Sodium Hydroxide
- What it does
- pH adjuster
- Where it comes from
- Mineral: made from salt water
- Vegan?
- Yes
Why it’s in a formula
In skincare it is used in small amounts to adjust a formula's pH, or to neutralise an acid or a thickener. It reacts as the product is made; what matters is the finished product's pH, not the lye that went in.
- It appears on the list because ingredients are named as they are added, not as they end up. The same is true of soap: all true soap is made with lye.
Where you’ll find it at Divina
Read from each piece’s published ingredient list. One piece.
Questions
Is sodium hydroxide safe in skincare?
Yes, in the small amounts used to set pH. It has reacted by the time the product is finished.
Why is sodium hydroxide in my cleanser?
To bring the formula to the right pH, or to neutralise another ingredient. It is listed because ingredients are named as they are added.
How we know: every ingredient list on this site is the manufacturer’s own, read piece by piece and shade by shade, and the pieces above are worked out from those lists each time the site is built. Ingredient names and functions follow the EU’s CosIng database. This page describes cosmetic ingredients; it isn’t medical advice.
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