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Antioxidant

Sodium Ascorbyl Phosphate

The stable form of vitamin C — sodium ascorbyl phosphate does not oxidize and does not yellow unlike pure ascorbic acid. Ideal for those who want the benefits of vitamin C without the risk of irritation and instability.

Vitamin CStable formBrighteningAntioxidant
✓ Safe
Comedogenic Rating
0/5
Irritation Potential
0/5

What is it?

Sodium Ascorbyl Phosphate (SAP) — sodium salt of ascorbyl-2-phosphate. In INCI: Sodium Ascorbyl Phosphate. A water-soluble form of vitamin C that converts to ascorbic acid after penetrating the skin by the enzyme phosphatase. Stable at pH 7 and above — does not oxidize in air and on the skin.

A gentle brightening and antioxidant active in daily serums, toners, and creams. The ideal form of vitamin C for sensitive skin that cannot tolerate pure ascorbic acid (pH 2.5–3.5).

Key Benefits

✦
Stability without yellowing and oxidation
SAP does not oxidize in air and does not change the color of the formula over time — unlike L-ascorbic acid, which yellows within a few weeks. Products maintain effectiveness throughout their shelf life.
◈
No irritation at pH 7
Effective at neutral pH — does not require an acidic environment (pH 2.5–3.5), which is the main source of redness and burning from vitamin C serums. Ideal for reactive and sensitive skin.
✧
Brightening and antioxidant protection
After conversion to ascorbic acid — inhibits tyrosinase and brightens pigmentation spots, neutralizes free radicals, and protects against UV stress. The effect is milder than that of pure ascorbic acid but more stable.

Suitable for

For sensitive skinFor skin with pigmentationFor all skin types

Main Actions

✓ Antioxidant protection✓ Brightening✓ Even skin tone✓ Stable form of vitamin C
Effectiveness compared to L-ascorbic acid

SAP is less effective than pure L-ascorbic acid at equal concentrations — due to the need for enzymatic conversion. However, stability and tolerability compensate for this. If the skin tolerates acidic ascorbic acid well — choose it. If not — SAP is an excellent alternative.

CategoryAntioxidants

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