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Ingredient guide
tetrahydromethylpyrimidine carboxylic acid
In short
Ectoin is a protective molecule from extremophile bacteria that helps skin retain moisture and stay comfortable under environmental stress. It’s known for its strong hydration and barrier‑supportive qualities.
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Works for
Hydration · Barrier
Skin type
Dry · Sensitive
Best used
Anytime
What it is
Full INCI form of ectoin, the extremolyte amino-acid derivative produced by halophilic bacteria; preferential exclusion mechanism stabilises stratum-corneum hydration and proteins under osmotic and UV stress; cross-references existing ectoin entries.
Also found as
Related
Where to find it
Eucerin Sun Fluid Hydro Protect SPF 50
Ultrasun Face Fluid SPF 30
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Common questions
It helps improve hydration levels and makes the skin feel more resilient in the face of dryness or sun exposure. Its protective action supports a smoother surface.
It works well for dry and sensitive skin, and for anyone seeking long‑lasting hydration.
It appears in serums, day creams, and sunscreens designed to keep skin hydrated and comfortable.
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Personal guidance only · For clinical concerns, see a dermatologist.