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Humectant

Lactic Acid

The gentlest AHA acid with dual action: exfoliates surface cells and moisturizes the skin, as it is a natural component of NMF. Perfect for first encounters with acids and for sensitive skin.

AHAExfoliantNMFHydration
✓ Safe
Comedogenic Rating
0/5
Irritation Potential
1/5

What is it?

Lactic Acid — AHA with a molecular weight of 90 Da (larger than glycolic acid 76 Da), providing a more superficial and gentle action. Used in cosmetics in the form of L-lactic acid or its salts (ammonium lactate, sodium lactate). Found in kefir and yogurt, which gave it its initial popularity in home care. Effective concentration: 5–10% at pH 3.0–4.0.

A gentle chemical exfoliant for all skin types, especially recommended for dry, sensitive skin and as a first acid product for beginners.

Key Benefits

✦
Gentle exfoliation + hydration at the same time
Unlike glycolic acid, lactic acid exfoliates and hydrates at the same time: it is part of the NMF (Natural Moisturizing Factor) — the skin's hydration system. Therefore, even with regular use, the skin does not dry out but becomes softer and smoother. An ideal choice for dry and dehydrated skin that needs exfoliation without drying.
◈
Brightening and evening out skin tone
Regular exfoliation with lactic acid accelerates cell renewal, reduces melanin levels in the upper layers, and gradually brightens pigmentation, post-acne, and uneven tone. The effect is gentler and slower than that of azelaic or mandelic acid, but with a lower risk of irritation.
✧
Stimulation of collagen synthesis and thickening of the dermis
Clinical studies show that regular use of AHA (specifically lactic acid) thickens the dermis and stimulates collagen synthesis. The effect develops with prolonged use (3–6 months) and is noticeable as a reduction in fine wrinkles and improvement in firmness.

Suitable for

For sensitive skinFor dry skinFor skin with uneven toneFor beginners with acids

Main Actions

✓ Gentle exfoliation✓ Hydration (NMF)✓ Brightening tone
Lactic Acid vs Glycolic Acid

Glycolic Acid (76 Da) — penetrates deeper, faster results, higher risk of irritation. Lactic Acid (90 Da) — gentler, exfoliates + moisturizes, ideal for sensitive skin and beginners. At the same pH and concentration, glycolic is more effective, but lactic is safer for daily use. For maximum brightening — a combination of both (as in many formulas).

CategoryHumectants
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