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Antioxidant

Ascorbic Acid

The pure, most-studied and most potent form of vitamin C — a powerful antioxidant and collagen-support active, but also the most unstable and potentially irritating form.

vitamin Cantioxidantbrighteningcollagen
✓ Safe
Comedogenic Rating
0/5
Irritation Potential
0/5

What is it?

Ascorbic acid (L-ascorbic acid) is the biologically active, unmodified form of vitamin C. It is highly effective but oxidizes quickly when exposed to light, air, and water, which is why it requires careful packaging (opaque, airless) and low pH formulation.

Used in brightening serums to even tone, support collagen synthesis, and provide antioxidant defense against UV and pollution-driven oxidative stress.

Key Benefits

✦
Brightens uneven tone
Inhibits melanin production at effective concentrations (typically 10-20%).
◈
Supports collagen synthesis
A required cofactor for enzymes involved in producing collagen.
✧
Strong antioxidant defense
Helps neutralize free radicals from UV exposure and pollution.

Suitable for

skin with uneven tone or dullnessskin tolerant of acidic activesnormal to oily skin

Main Actions

✓ brightening✓ antioxidant protection✓ collagen support
When it may be insufficient

Its low pH can irritate sensitive or compromised skin. More stable derivatives (ascorbyl glucoside, MAP, SAP) are gentler alternatives, though typically less potent.

CategoryAntioxidants
From our blog
Vitamin C in Skincare: Forms, Concentrations & How to Use It

Frequently Asked Questions

What does Ascorbic Acid do for skin?
Used in brightening serums to even tone, support collagen synthesis, and provide antioxidant defense against UV and pollution-driven oxidative stress.
Who should use Ascorbic Acid?
Ascorbic Acid is suitable for: skin with uneven tone or dullness, skin tolerant of acidic actives, normal to oily skin.
Are there any warnings about Ascorbic Acid?
Its low pH can irritate sensitive or compromised skin. More stable derivatives (ascorbyl glucoside, MAP, SAP) are gentler alternatives, though typically less potent.

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