Retinaldehyde (Term)

Retinaldehyde (Term) — a vitamin A derivative, also called retinal, that sits one conversion step away from retinoic acid, the active form of vitamin A in skin. This makes it more potent than retinol while still being available in over-the-counter products, and it is studied for effects on texture, tone, and signs of aging.

Key points

• Retinaldehyde converts to retinoic acid in a single enzymatic step, whereas retinol requires two.
• It is generally considered more potent than retinol but is still available without a prescription.
• Retinaldehyde can be less irritating than prescription retinoic acid for some users at comparable results.
• Like other retinoids, it can increase sun sensitivity and cause initial dryness or flaking.

Frequently asked

Is retinaldehyde stronger than retinol?

Retinaldehyde is generally regarded as more potent than retinol because it is only one conversion step from active retinoic acid, though tolerance and results vary by person.

Can retinaldehyde be used with acids?

It can be combined with acids, but layering multiple actives may increase irritation, so many people separate them or introduce them gradually. Educational only, not medical advice.

Related topics

• What Is a Humectant?
• What Is the Skin Barrier?
• Reef-Safe (Term)
• Physical Exfoliation (Term)
• Oxidative Stress (Term)
• Melanin (Term)
• Inflammation (Term)
• Hyperpigmentation (Term)

This is a foundational entry in the SYNC Skin Encyclopedia and is expanded over time. Educational information only — not medical advice.