Guanine
Reviewed by Kate · Last updated 18 Aug 2026
Functions: Colourant, Opacifying
EWG Safety Score
What Is Guanine?
Guanine is a cosmetic ingredient. It is grouped in the Coloring Agent/Pigment category on this site.
There is limited independent published research on its topical use, so this entry describes what the ingredient is rather than making specific performance claims.
Regulatory information
Standardised cosmetic-ingredient identifiers used by regulators.
Show identifiers
- INCI Name
- GUANINE
- EC Number
- 200-799-8
- Function
- Opa CI Fying
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