How to Layer Skincare Ingredients Correctly

By Dr Claudia Moreau | Skincare Science | The International Institute of Beauty

In the modern skincare era, more consumers are turning into at home chemists layering serums, acids, antioxidants and peptides in hopes of achieving luminous, healthy skin. Yet with the abundance of potent actives and complex formulations available today, one question consistently arises: How should we layer skincare ingredients correctly for maximum efficacy and minimal irritation?

Layering skincare is not merely about order; it is about synergy, stability, and respecting the skin’s natural barrier. In this article, we will explore an evidence based approach to skincare layering, taking into account molecular weight, pH compatibility, and current dermatological best practices.

Contact us to report infringement.

Why Layering Matters

The concept of skincare layering is rooted in basic dermatopharmacology. For an ingredient to be effective, it must penetrate the stratum corneum and reach its target whether that’s the epidermis, dermis, or superficial sebaceous glands. Layering products incorrectly can result in reduced efficacy, irritation, or even barrier disruption.

The correct sequence allows for optimal absorption, maintains skin homeostasis, and ensures that active ingredients do not inactivate one another a common mistake in poorly structured routines.

The Golden Rule: Thinnest to Thickest

The most universally accepted principle is to apply products from thinnest to thickest texture. This generally means:

1. Cleansers

2. Toners / Essences (optional)

3. Water based Serums (e.g. hyaluronic acid, niacinamide)

4. Oil based Serums (e.g. squalane, facial oils)

5. Moisturisers

6. Oils or Balms (if needed)

7. SPF (in the morning)

   
   

This approach maximises absorption, particularly of low viscosity, water soluble actives which can struggle to penetrate once occlusive agents have been applied.

Key Ingredient Interactions: What Works Together and What to Avoid

1. Retinoids and Acids

Retinoids (including retinol, retinaldehyde and prescription strength tretinoin) are sensitive to pH and prone to inactivation. Using them alongside alpha hydroxy acids (AHAs) or beta hydroxy acids (BHAs) in the same routine increases the risk of irritation, particularly in sensitive skin.

Best practice: Use acids in the morning or on alternate nights, and retinoids in the evening. Alternatively, wait 30–45 minutes between applying acids and retinoids to reduce compounding irritation.

2. Vitamin C and Niacinamide

For many years, it was believed that these two actives neutralise each other. However, modern research has dispelled this myth. Vitamin C (ascorbic acid) and niacinamide can be layered safely, and may even offer synergistic antioxidant protection and brightening effects.

Best practice: Layer vitamin C serum first, followed by niacinamide serum or moisturiser.

3. Hyaluronic Acid and Everything

Hyaluronic acid (HA) remains the most universally compatible ingredient. It functions as a humectant and is typically applied directly after cleansing to damp skin, followed by an occlusive moisturiser to seal in hydration.

Best practice: Use HA as a base layer in both morning and evening routines. It can be safely combined with actives like retinol, acids, peptides, and antioxidants.

4. Peptides and Acids/Retinoids

Some peptides, particularly signal peptides, are pH sensitive and may degrade in highly acidic environments. Layering peptides immediately after AHAs or BHAs may compromise their effectiveness.

Best practice: Use peptides on alternate nights or apply after a barrier repairing serum or moisturiser to buffer their activity.

Morning vs Evening Routines: What to Layer When

Morning (AM) Routine Goals: Protect and hydrate

• Cleanser (gentle, non stripping)

• Antioxidants (e.g. vitamin C, ferulic acid)

• Hydrator (e.g. hyaluronic acid)

• Barrier support (e.g. niacinamide, ceramides)

• Moisturiser

• Broad spectrum SPF (at least SPF 30)

Evening (PM) Routine Goals: Repair and regenerate

• Cleanser (can be double cleanse if wearing makeup)

• Exfoliant (2–3 times per week, e.g. glycolic or salicylic acid)

• Treatment (e.g. retinoids, peptides)

• Hydrator

• Barrier repairing moisturiser or facial oil

The Role of pH in Skincare Layering

pH compatibility is often overlooked, but crucial for product efficacy. The skin’s natural pH is between 4.5 and 5.5. Most actives perform best within specific pH ranges:

• AHAs: pH 3–4

• Vitamin C (ascorbic acid): pH <3.5

• Retinoids: neutral to slightly acidic

• Niacinamide: pH 5–7

Using a high pH product after a low pH active can neutralise its benefits. Therefore, actives like vitamin C should be applied early in the routine and allowed to absorb before applying more neutral or alkaline products.

Simplification: Less Is Often More

While layering can be effective, excessive product use may compromise the skin barrier. In clinical practice, I often recommend a “skincare fast” for patients experiencing sensitivity, scaling their routine back to a gentle cleanser, basic moisturiser, and SPF for two weeks before reintroducing actives one at a time.

How to Introduce New Ingredients into a Layering Routine

When adding new products to a regimen:

1. Patch test on a discreet area for 24 48 hours.

2. Introduce slowly start with twice a week, then increase frequency.

3. Avoid adding multiple actives at once to identify irritants if reactions occur.

4. Monitor your skin for signs of improvement or barrier distress.

   
   

Common Mistakes to Avoid

• Applying oils before water based serums: This prevents hydration from penetrating the skin.

• Mixing too many actives: This increases the risk of irritation and reduces efficacy.

• Skipping SPF after actives: Acids, retinoids, and vitamin C increase sun sensitivity.

• Over exfoliating: More is not better. Limit acids to 2–3 times per week, depending on tolerance.

Conclusion: Precision Over Popularity

Correctly layering skincare ingredients is not about following trends it is about understanding how your skin functions, and how each ingredient interacts chemically and biologically. A well structured routine should respect the skin’s integrity while delivering measurable benefits over time.

As a dermatologist, I always advise prioritising skin tolerance, simplicity, and formulation quality over the sheer number of products. Layer thoughtfully, protect your barrier, and give your skin the consistency it needs to thrive.