Humectants and Hyaluronic Acid in Skincare

Hydration, hydration, hydration.

This is what valuable humectants bring to your skin.

They are the antidote for dehydrated and dry skin conditions.

A lot of terms get tossed around in the beauty world. Some are easy, some not so much.

Were here to help make the muddled world of beauty terminology a little less confusing, and for this article, we’re exploring hydrating humectants.

All skin types require water

All skin requires hydration – even an oily skin type – if we remember dry skin lacks oil, and dehydrated skin lacks water, a subject w discuss in the article, “The Clear Skin Difference: It Begins With Hydration.“, Your skin requires a mixture of both oil-rich and water-rich ingredients to be healthy.

• some natural botanical oils found in skincare products, such as jojoba or squalane, mimic your skin’s natural oil, sebum.
• humectant ingredients are water-rich; they mimic your skin’s sweat and work by hydrating your skin. They have been specifically designed to prevent water loss and protect the stratum corneum, the epidermis from becoming dry and parched.

The role of humectants

Without getting too technical, a humectant’s key functionality is to form hydrogen bonds with water molecules; this is why humectants are considered an important ingredient if you have dry or dehydrated skin.

We like to add humectants to our formulas because of their ability to attract water like a magnet; physically binding water to them. Some humectants can hold up to 1000 times their own weight in water; Hyaluronic Acid, found in our H₂O Hydrating Complex, is one such ingredient. It locks moisture onto the surface of the skin, keeping it moist and healthy, Quench contains five important humectants.

Why is skin hydration so important?

Water is essential to the normal functioning of your skin. The skin’s intercellular communication system regulates the amount of water it loses via trans-epidermal water loss; a function that can only work correctly if your skin’s barrier function isn’t damaged. Skin with an impaired moisture barrier has an increased rate of trans-epidermal water loss, resulting in rough, dry, and flaky skin, which becomes prone to inflammation, irritation, premature ageing, and skin conditions eczema.

If your skin is not adequately hydrated it can’t perform important functions correctly like desquamation, which is your skin’s natural exfoliation process, and the formation of the cornified cells is hindered, which is important for creating the protective barrier – your skin’s first line of defence against environmental damage. This is not the only thing that increases trans-epidermal water loss; humidity changes, high pH cleansers, and astringents may also result in more water loss from your skin.

Does our skin naturally contain humectants?

Yes, it does contain natural humectants. These are collectively referred to as the skin’s natural moisturising factor – or the NMF for short, and their role is to form a protective coat that keeps your outer layer of skin adequately hydrated. This natural skin moisturiser is primarily made up of hyaluronic acid, lactic acid, sodium, urea, various sugars and amino acids; including pyroglutamic acid, the precursor of sodium PCA.

Studies have found, that not only does the NMF work to increase the water content in your stratum corneum, but specific components especially glycerol and urea, work to retain the fluidity of proteins and lipids under dehydrating conditions. Thus ensuring that your skin will still carry out important functions, even in dehydrating conditions.

Because these ingredients deplete with age, this can cause several conditions including; sensitivity, inflammation, dehydration, dryness and inflamed breakouts.

Many of the Naked Chemist skincare products are formulated to mimic the NMF by using a combination of humectants, emollients, and occlusive. Without these natural humectants keeping your skin soft and supple, the barrier repair function would out of balance, making your skin less permeable to water and other beneficial ingredients.

This is why humectants are precious ingredients, not only do they help to hydrate your skin, but they repair and replenish, helping to ward off premature ageing, whilst helping other compounds ingredients to penetrate more effectively.

Humectants decrease with age

As you age, the level of humectants naturally present in your skin decreases; this is why you start to experience drier and more dehydrated skin. Therefore, replenishing the NMF through the external application of skincare products containing humectants will help to keep your skin moist, plump and more youthful.

Types of humectants used in skincare

• Hyaluronic Acid has potent hydrating capabilities. It can hold anywhere between 600 – 1000 times its own weight in water; perfect if you have parched, dehydrated skin
• Glycerin is also referred to as glycerine and glycerol. In fact, glycerin is found in natural fat or lipids; it is an extremely safe and non-allergenic skincare ingredient and has a long history of use. This is a powerful humectant that works really well as a hydrating agent, and we love that it keeps on working long after the product has been rinsed off your skin
• Urea is a little known but significant water-loving agent which you can read about here
• Whilst we don’t use this in our formulas, butylene glycol is an ingredient you will often find in skincare products for dry skin; it is more popular than propylene glycol, which can irritate sensitive skin due to its permeability
• Sorbitol is an ingredient that often replaces glycerine; it is a great hydrating agent with similar benefits
• Sodium PCA is similar to hyaluronic acid; this ingredient works really well to hydrate your skin, you can read more about sodium PCA here
• Seaweed and algae are perfect for hydrating mask formulas; they work by creating a moist film over your skin’s surface, helping to retain water in your skin’s upper layers. These ingredients are extremely nourishing and moisturising

Urea is an important humectant

When used at concentrations below 10%, it is one of the most effective humectants comprising about 8 per cent of the natural moisturising factor. In fact, healthy, non-dehydrated skin will typically contain around 28 micrograms of urea per square centimetre, so you can see why it is an important humectant.

Interestingly, xerotic skin conditions or abnormally dry skin is associated with a huge reduction in the concentration of urea in the skin, up to 30% less in the skin with those who have psoriasis and as much as 85% less in the skin with those suffering from eczema.

It is as effective as glycerin at keeping your skin moist and hydrated – and imparts a more favourable, less sticky skin feel. Unlike hyaluronic acid and urea, it readily penetrates your skin.

Urea actually has three additional benefits for your skin:

• it encourages natural exfoliation of your skin cells when used at concentrations that are higher than 10%, by breaking down intercellular bonds between the dead cells – this is why urea is the  perfect ingredient for treating keratosis pilaris and hard, dry skin on the feet
• it is extremely penetrative – because it breaks down these bonds, thus helping other skincare ingredients to penetrate more effectively
• it helps to regulate microbes on your skin, thereby replenishing the acid mantle and rebuilding your skins barrier function
• studies are also finding that urea may be effective in treating fungal acne, as it inhibits the yeast Malassezia

And yes, urea is also a component of urine; however, there’s no need to be grossed out, because when it comes to the urea used in your skincare products, it is synthetically-derived.

The naked truth

Using humectants can be a double-edged sword. Humectants are really good at attracting water molecules to the skin, but you have to consider where the water molecules come from, and how it affects your skin.

Humectants pull water molecules from their surrounding environment. In most cases, this is of course, from the air, if the humidity is high enough – which is generally greater than 80%. However, if you live in a dry climate and there is not much moisture in the air, then chances are that the humectants will actually pull water from the deeper layers of your skin, which can cause dehydration problems.

This interesting article is on the correlation between barrier function and trans-epidermal water loss; it shows a general pattern of decreasing water loss with the rising humidity.

So does this mean we should be avoiding humectants if we live in a dry climate? Not at all, you just need to apply your humectant product such as H20 or Quench and layer with your chosen moisturiser, to ensure you are locking all that skin hydrating, plumping goodness against your skin.