Oil-Based Serum vs Water-Based Serum: What’s the Difference for Mature Skin?

When we hear the word serum, many of us picture a lightweight, water-based formula applied before moisturiser. But not all facial serums are water-based.

Serums can be formulated in different ways, including water-based, emulsion-based and oil-based formulations. What matters is not simply whether a serum contains water or oil, but what it is designed to deliver, how it feels on the skin and where it fits within your skincare ritual.

For mature skin in particular, understanding these differences can help you choose a serum that supports your skin's changing needs without unnecessary complexity.

What Is a Facial Serum?

A facial serum is generally a concentrated skincare formulation designed to deliver selected ingredients to the skin.

Unlike a moisturiser, which primarily helps hydrate, soften and support the skin's protective barrier, a serum is often formulated with a more targeted purpose.

Depending on its formulation, a serum may be designed to support the appearance of:

• Dryness and loss of suppleness

• Dull or tired-looking skin

• Uneven-looking skin tone

• Fine lines and visible signs of ageing

• Overall radiance and skin comfort

The word serum, therefore, doesn't automatically mean water-based.

What Is a Water-Based Serum?

Water-based serums use water as the principal base of the formulation.

They are often very light in texture and may contain water-soluble ingredients such as humectants and botanical extracts.

Because of their lightweight nature, they are generally applied before creams and oils.

For some skin types, particularly younger or oilier skin, a water-based serum may provide the light texture they prefer.

Mature skin, however, often has different needs.

What Is an Emulsion-Based Serum?

An emulsion-based serum combines both water and oil phases within the same formulation.

Because water and oil don't naturally remain mixed together, an emulsifying system is used to create a stable formulation. This allows both water-soluble and oil-soluble ingredients to be incorporated into one serum.

Depending on how it is formulated, an emulsion-based serum can range from very light and fluid to creamy in texture.

It essentially sits between a predominantly water-based serum and an oil-based serum, offering characteristics of both.

What Is an Oil-Based Serum?

An oil-based serum is formulated predominantly with oils and oil-soluble ingredients rather than a conventional water phase.

That doesn't necessarily make it the same as what consumers commonly think of as a traditional face oil.

A well-formulated oil-based serum can be elegant and lightweight, absorb beautifully and leave the skin feeling comfortable and nourished without a heavy or greasy residue.

This distinction was particularly important to me when developing the LA MAXIME Glow Face Serums.

I wanted the benefits and formulation possibilities offered by carefully selected botanical oils, but I didn't want the products to feel like conventional facial oils.

The result was an oil-based face serum with a lightweight, non-greasy finish.

Why Mature Skin Can Benefit From Lipid-Rich Skincare

As skin matures, it can become progressively drier and less able to retain moisture effectively.

The skin's natural lipid composition also changes with age. This can contribute to feelings of dryness, tightness and reduced suppleness.

This is one reason oils and other lipid-based ingredients can have an important place in a mature skincare ritual.

But that doesn't mean mature skin necessarily needs a heavy or greasy facial oil.

Formulation matters.

Oil-Based Doesn't Have to Mean Oily

This is perhaps one of the biggest misconceptions surrounding oil-based skincare.

The words oil-based can immediately make us imagine something thick, shiny or greasy sitting on the surface of the skin.

But different botanical oils have very different characteristics.

Their fatty-acid profiles, viscosity, absorption characteristics and the way they are combined all influence how the finished formulation behaves on the skin.

A thoughtfully formulated oil-based serum can feel remarkably light.

This is why the formulation as a whole matters more than simply seeing the word oil on an ingredient list.

Why LA MAXIME Calls Them Glow Face Serums — Not Face Oils

When I created the LA MAXIME Glow Face Serums, deciding what to call them wasn't as straightforward as it might seem.

Technically, they are oil-based formulations.

But I didn't want to call them face oils because that description didn't accurately communicate how I had designed them to be used or how they felt on the skin.

They were created as concentrated treatment steps within a structured skincare ritual.

They are oil-based, but they are not designed to leave the skin feeling oily or greasy.

For me, Glow Face Serum was the description that best reflected both their purpose and their sensory experience.

Today, LA MAXIME has two Glow Face Serums, each created to play its own role within our approach to mature skincare.

Oil-Based Serum vs Moisturiser: Do You Need Both?

This is another common question.

A serum and a moisturiser perform different roles, so one doesn't necessarily replace the other.

An oil-based serum can provide concentrated botanical oils and oil-soluble ingredients while supporting softness, suppleness and radiance.

A moisturising cream performs a broader role in helping maintain hydration and supporting the skin barrier.

For mature or dry skin, using both can therefore make sense.

The order in which they're used also matters.

Within the LA MAXIME Skin Glow 5™ Ritual, skincare is applied in a considered sequence so that each formulation complements the next rather than simply layering products without purpose.

What About Facial Oils?

There is absolutely a place for facial oils in skincare.

For someone who enjoys a simple oil product, a traditional facial oil may be exactly what they're looking for.

But facial oil and oil-based serum shouldn't automatically be treated as interchangeable terms.

A product's purpose, formulation, ingredient composition, texture and recommended method of use all matter.

This is why I prefer to describe the LA MAXIME Glow Face Serums precisely for what they are:

Oil-based facial serums formulated to provide concentrated skincare benefits with a lightweight, non-greasy finish.

Choosing a Serum for Mature Skin

Rather than choosing a serum simply because it is described as water-based or oil-based, consider what your skin actually needs.

Ask yourself:

• Does my skin frequently feel dry or tight?

• Has my skin become less supple with age?

• Do I want greater radiance?

• Does my current serum leave my skin feeling comfortable?

• Am I layering several products without understanding what each one contributes?

For mature skin, a simpler and more structured approach can often be more useful than continually adding another product.

The LA MAXIME Approach

At LA MAXIME, our philosophy is based on consistency, structure and purposeful formulation.

The Skin Glow 5™ Ritual was developed around five essential stages:

Cleanse. Renew. Balance. Nourish. Seal.

Rather than asking mature skin to navigate an increasingly complicated routine, each stage has a defined purpose.

Our Glow Face Serums form part of that philosophy: concentrated, oil-based formulations designed specifically with mature skin in mind, while maintaining the lightweight, elegant skin feel that has always been important to me as a formulator.

Because ultimately, mature skincare doesn't need to be complicated.

It needs to be considered, consistent and beautifully formulated.