Sodium Citrate
A gentle pH buffer and stabilizer. Sodium Citrate is the sodium salt of citric acid, used in skincare to maintain pH balance, improve stability of actives, and enhance comfort in formulations containing antioxidants or exfoliating acids.
Where Does Sodium Citrate Come From?
Sodium Citrate is derived from citric acid, which is itself produced by fermenting sugars (traditionally citrus-based). It’s valued for both food and cosmetic applications as a safe, naturally-associated buffering agent.
Sodium Citrate vs. Citric Acid
| Feature | Citric Acid | Sodium Citrate |
|---|---|---|
| Primary Role | pH adjuster, antioxidant, mild exfoliant | Buffer, stabilizer for sensitive actives |
| Skin Feel | Can be tingly at higher levels | Gentle, neutral, comfort-preserving |
| Best For | Exfoliating toners, cleansers, Vitamin C serums | Vitamin C blends, calming serums, balanced cleansers |
| pH Range | 3.0–6.0 | 5.0–7.0 |
| Source | Fermentation of citrus sugars | Neutralized citric acid (fermentation-based) |
Why Is Sodium Citrate Used in Skincare?
- pH Buffer – Keeps formulations in the ideal skin-friendly range.
- Stability Booster – Protects Vitamin C and other sensitive actives from degradation.
- Comfort Enhancer – Reduces irritation potential of exfoliating acids.
Best Paired With
- Vitamin C (SAP, MAP, AA) – Improves formula stability and longevity.
- AHAs (like Citric or Glycolic Acid) – Buffers intensity for gentler exfoliation.
- Niacinamide – Helps keep formulations stable and skin barrier balanced.
Fun Facts About Sodium Citrate
Fun Fact #1
Sodium Citrate is widely used in both food and skincare as a safe buffer system.
Fun Fact #2
It helps Vitamin C serums stay fresher longer by preventing unwanted pH shifts.
Fun Fact #3
Though derived from citric acid, it’s much gentler on the skin’s surface.
Final Thoughts
Sodium Citrate is a quiet but crucial skincare helper—ensuring formulas stay stable, gentle, and effective. By buffering acids and supporting antioxidants, it improves both performance and user comfort in modern formulations.
