Alpha hydroxy acids (AHA)
Lactic acid
INCI: Lactic Acid · AHA
Can support hydration in the right formula, but exfoliation makes it less universally gentle than classic humectants.
What it is best suited for
What result is realistic
A realistic improvement is possible with consistent use, but response varies by formula and context.
- Initial change
- Several weeks
- When to evaluate
- About 8–12 weeks
- Expected benefit
- Modest
What it is and what we know
An exfoliating acid that can also contribute humectancy, often positioned as a gentler AHA option.
Its usefulness depends on the goal, vehicle, concentration context, frequency, and the rest of the routine.
Who may find it irritating
Irritation potential: Moderate. Formula, frequency, and barrier condition change tolerability.
No special restriction is modeled here, but individual products and circumstances still matter. The ingredient may increase irritation or sun vulnerability in context. Daily broad-spectrum protection remains important.
How a beginner can introduce it
Introduce consistently in a simple routine and adjust to tolerance.
Useful concentration depends on the ingredient form and complete formula. Ingredient order alone cannot establish a studied concentration.
What not to expect
No single ingredient guarantees a result or compensates for an irritating, inconsistent routine.
Ingredient evidence does not guarantee that every product formula performs equally.
What may duplicate it
Alpha hydroxy acids (AHA) is its functional family. Several products from this family can repeat the same role, especially when they are irritation-prone.
Same family: Glycolic acid · Mandelic acid.
Verified products containing it
No verified product yet
TIER does not recommend a formula without an official source. Compare the next-ranked ingredient while the verified catalogue grows.
View the next alternative →Evidence and uncertainty
Editorial preview. Complete source lists and clinical review are not yet published. TIER therefore avoids “best” claims and does not show a public numeric score.
Hydration · Moderate
- Evidence certainty
- Moderate
- Editorial confidence
- Medium
- Published sources
- 0
- Status
- Editorial preview
- Last reviewed
- 2026-07-14
The priority score combines evidence confidence, expected benefit, tolerability, practicality, time, and relative cost. It is not an efficacy percentage.
Important uncertainty: Ingredient evidence does not guarantee that every product formula performs equally.
Next best alternative
Glycerin is the next-ranked option for Hydration. Compare it before adding another active.
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