Humectants, Emollients and Occlusives Explained Simply

When you start making your own skincare products, you will quickly come across terms such as humectants, emollients and occlusives.

They may sound complicated, but once you understand what each one does, formulating lotions, creams, serums and body products becomes much easier.

These three groups of ingredients all contribute to the way a product moisturises and conditions the skin, but they work in different ways.

Let’s break them down in simple terms.

What Does “Moisturising” Actually Mean?

When we talk about moisturising the skin, we are generally talking about helping the skin retain water, improve its softness and reduce excessive moisture loss.

A well-formulated moisturiser can use a combination of humectants, emollients and occlusives to achieve these different functions.

Think of them as three different members of a team:

Humectants attract and hold water.
Emollients soften and smooth the skin.
Occlusives help reduce water loss from the skin.

Using the right combination can produce a much more effective moisturising product.

1. What Are Humectants?

Humectants are ingredients that help attract and hold water.

They are commonly used in lotions, creams, serums, facial products, haircare products and other water-based formulations.

Humectants can help give the skin a hydrated, plump and comfortable feeling.

Common humectants include:

Glycerine
Hyaluronic acid
Sodium PCA
Panthenol
Propanediol
Sorbitol
Sodium lactate

Glycerine

Glycerine is one of the most widely used humectants in skincare.

It is particularly useful in lotions, creams, liquid soaps and other water-containing formulations.

Glycerine can help improve the skin’s hydration and can also contribute to a pleasant skin feel.

Hyaluronic Acid

Hyaluronic acid is another popular humectant.

It is capable of binding water and is frequently used in facial serums, moisturisers and hydrating products.

Hyaluronic acid is available in different forms and molecular weights, so formulators should always follow the supplier’s recommended usage rate and processing instructions.

Sodium Lactate

Sodium lactate is a humectant that is also widely used in cosmetic formulation.

It can be particularly useful in lotions and other moisturising products and is also well known among soap makers for its role in cold process soap making.

2. What Are Emollients?

Emollients are ingredients that help soften and smooth the skin.

They are often oils, butters, esters and other lipid-based ingredients.

Emollients can improve the skin feel of a product and help make the skin feel smoother and more comfortable.

Examples include:

Jojoba oil
Sweet almond oil
Olive oil
Sunflower oil
Shea butter
Cocoa butter
Caprylic/capric triglyceride
Cosmetic esters

Different emollients have very different characteristics.

Some feel light and silky, while others are richer and heavier.

This gives the formulator considerable flexibility when creating a product.

Choosing the Right Emollient

If you want a lightweight facial lotion, you may prefer lighter-feeling oils or cosmetic esters.

For a rich body butter designed for very dry skin, you might choose richer oils and butters.

This is why simply choosing an ingredient because it is described as a “good moisturising oil” isn’t enough.

You also need to consider:

Skin feel
Absorption
Stability
Oxidative sensitivity
Compatibility with the formulation
Intended product type

3. What Are Occlusives?

Occlusives work differently.

Rather than primarily attracting water or simply softening the skin, occlusive ingredients help form a barrier that can reduce transepidermal water loss (TEWL).

In simple terms, they help slow down the amount of water escaping from the skin.

Examples of occlusive ingredients include:

Petrolatum
Mineral oil
Lanolin
Waxes
Certain plant butters
Dimethicone

The effectiveness and skin feel of different occlusives can vary considerably.

For example, petrolatum is highly occlusive, while waxes can also contribute to a protective film but have different properties and formulation uses.

Humectants + Emollients + Occlusives

Now we can see why formulators often use a combination of these ingredient groups.

Imagine making a moisturising body lotion.

You might have:

Humectant: Glycerine
Helps attract and hold water.

Emollient: Jojoba oil
Helps soften and smooth the skin.

Occlusive: An appropriate protective ingredient
Helps reduce moisture loss.

Together, these ingredients can provide different aspects of moisturisation.

However, this does not mean that every moisturiser needs all three categories in large amounts.

Formulation is about balance.

Can a Single Ingredient Do More Than One Job?

Yes.

Cosmetic ingredients don’t always fit neatly into one category.

Some ingredients can provide several functions depending on their concentration and the formulation.

For example, certain oils and butters can provide both emollient and occlusive characteristics.

This is one reason cosmetic formulation is more complicated than simply following a list of ingredients.

The final result depends on:

Ingredient selection
Usage levels
Processing method
pH
Emulsifier system
Preservative system
Product type
Packaging
Skin feel
Stability

Why More Isn’t Always Better

A common beginner mistake is thinking:

“If glycerine is good for hydration, adding lots more must be better.”

Not necessarily.

Too much of an ingredient can negatively affect the texture, skin feel or stability of a formulation.

The same principle applies to oils, butters, humectants and other functional ingredients.

Always follow the supplier’s recommended usage rates and formulate according to the intended product.

What About Dry Skin?

For dry skin, a formulation containing a combination of humectants, emollients and appropriate occlusive ingredients can be useful.

For example:

Humectants can help provide hydration.

Emollients can help improve softness and smoothness.

Occlusives can help reduce moisture loss.

The exact formulation should depend on the product being made and the intended skin feel.

What About Oily Skin?

Oily skin doesn’t necessarily mean the skin doesn’t need moisturising.

The trick is often choosing ingredients and textures that provide hydration without leaving the skin feeling excessively greasy.

Lightweight humectants, suitable emollients and carefully selected supporting ingredients can be used to create lighter moisturising products.

This is where formulation becomes particularly interesting.

A Simple Way to Remember the Difference

If you are new to formulation, remember:

HUMECTANTS

“Bring in water.”

Examples: Glycerine, hyaluronic acid, sodium PCA and sodium lactate.

EMOLLIENTS

“Soften and smooth.”

Examples: Jojoba oil, almond oil, olive oil and shea butter.

OCCLUSIVES

“Help keep moisture from escaping.”

Examples: Petrolatum, mineral oil, waxes, lanolin and dimethicone.

The Importance of a Balanced Formula

A good moisturiser isn’t simply a collection of ingredients that are individually considered “good for the skin.”

The ingredients need to work together.

You also need to consider preservation, pH, emulsification, stability and the intended use of the finished product.

This is why cosmetic formulation is both a science and an art.

Understanding the role of each ingredient is the first step towards creating better products.

Final Thoughts

Once you understand the difference between humectants, emollients and occlusives, cosmetic formulation becomes much easier to understand.

Instead of looking at an ingredient list and wondering what each ingredient does, you can begin to recognise the role different ingredients play.

Remember:

Humectants help attract and hold water.

Emollients help soften and smooth the skin.

Occlusives help reduce moisture loss.

When carefully combined in the right formulation, these different ingredients can work together to create a moisturising product with excellent skin feel and performance.

Want to Learn More About Cosmetic Formulation?

At Fun with Soap, we love making cosmetic formulation easier to understand.

Whether you’re a beginner experimenting at home or you’re developing products to sell, understanding your ingredients is an important part of becoming a confident formulator.

Visit www.funwithsoap.co.za for cosmetic ingredients, soap-making supplies, kits, recipes and educational resources.