Acetyl Tetrapeptide-40

INCI: ACETYL TETRAPEPTIDE-40

Also known as: Acetyl Tetrapeptide-40

A peptide that supports the skin's natural lipid production and barrier function

At a glance

Peptide

Best For Skin Types

All, Dry, Sensitive, Mature

Addresses

Dryness, Barrier repair, Hydration

Usage Frequency

Daily

What Is Acetyl Tetrapeptide-40?

Acetyl tetrapeptide-40 is a synthetic peptide—a short chain of amino acids—designed to influence the skin's lipid metabolism and barrier health. Peptides work by signalling to skin cells, in this case encouraging processes related to lipid (fat) synthesis, which is essential for maintaining the skin's protective barrier.

The ingredient functions as a skin conditioner, helping to support the structural integrity and hydration capacity of the epidermis by promoting healthy lipid production in this outermost layer.

How It Works

Acetyl tetrapeptide-40 appears to work by signalling skin cells—particularly those in the epidermis—to optimise their lipid synthesis pathways. The skin barrier is composed largely of lipids (ceramides, cholesterol, and fatty acids), and maintaining adequate lipid production is crucial for barrier function.

By supporting the skin's own lipid-producing mechanisms, this peptide helps ensure the barrier remains intact and effective at minimising water loss and defending against environmental stressors.

Clinical Evidence & References

Research into acetyl-CoA metabolism and skin homeostasis suggests that lipid production in the epidermis is fundamental to barrier health and systemic skin function. Studies have identified key regulatory pathways involved in how skin cells synthesise the lipids needed for barrier integrity.

Whilst the specific effects of acetyl tetrapeptide-40 have not been extensively documented in published clinical trials, the underlying science supports the rationale that promoting healthy lipid metabolism can benefit barrier function and skin hydration. Further targeted research would help establish its efficacy profile more definitively.

How to Use

This ingredient is typically found in moisturisers, serums, and barrier-support formulations. Apply to clean skin as part of your regular routine, ideally both morning and evening. Peptide ingredients are generally stable but benefit from being layered with other hydrating or occlusive ingredients to maximise their conditioning effects.

Safety & Precautions

Acetyl tetrapeptide-40 is generally well-tolerated and suitable for most skin types. As with any peptide ingredient, patch test if you have very sensitive skin or are prone to reactions.

Regulatory information

Standardised cosmetic-ingredient identifiers used by regulators.

Show identifiers
INCI Name
ACETYL TETRAPEPTIDE-40
Function
Skin Conditioning

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