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Sebacic Acid

INCI: SEBACIC ACID

Reviewed by Rosie · Last updated 14 Aug 2026

A buffering agent that helps stabilise pH in skincare formulations

Best For Skin Types

All

Usage Frequency

Daily

What Is Sebacic Acid?

Sebacic acid is a naturally occurring dicarboxylic acid derived from castor oil. In skincare formulations, it functions primarily as a pH buffer—a compound that helps maintain the acidity or alkalinity of a product to keep it stable and suitable for skin application.

Because it is rarely used as a standalone active ingredient, sebacic acid's role in a skincare product is largely behind-the-scenes. Its presence helps ensure that other actives and preservatives in the formula work as intended by maintaining the correct pH environment.

How It Works

Sebacic acid acts as a buffer by accepting or donating hydrogen ions, which keeps the pH of a formula within a target range. This is important because many skincare actives—such as vitamins, peptides, and botanical extracts—are only stable and effective within a narrow pH window.

By maintaining this optimal pH, sebacic acid indirectly supports the efficacy of the other ingredients in the product, rather than providing a direct benefit to the skin itself.

Clinical Evidence & References

Sebacic acid is well established in cosmetic chemistry as a safe and effective buffering agent, though formal clinical studies evaluating it as a skincare ingredient are limited. Its role is primarily functional rather than therapeutic.

Research on dicarboxylic acids more broadly suggests buffering compounds are essential for maintaining the stability and safety of skincare formulations. However, the direct skin benefits of sebacic acid specifically have not been extensively documented in published dermatological literature.

How to Use

Sebacic acid is an ingredient you will rarely notice on a label because it works quietly to support the overall performance of a product. Simply use your formulation as directed by the brand, with the knowledge that this buffer is working to keep your actives stable and effective.

Safety & Precautions

Sebacic acid is generally recognised as safe in cosmetic formulations and is well-tolerated by most skin types. No specific cautions are widely reported for topical use at typical concentrations.

Frequently Asked Questions

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