The hydrolipidic film and our skin's lipid cement: everything you need to know about skin lipids

• The lipids found in the hydrolipidic film and the skin’s lipid cement (or “extracellular matrix”) help maintain adequate skin hydration by forming a moisture barrier.

• The hydrolipidic film consists of sebum and sweat, while the skin’s lipid cement is composed of ceramides, cholesterol, and polyunsaturated fatty acids.

• As we get older, skin lipid production declines, weakening the skin barrier and leading to dehydrated skin, which in turn leads to problems like dryness and loss of firmness.

• A gentle, pH-balanced skincare routine, rich in lipids and moisturizing active ingredients, plays a vital role in restoring and maintaining the health of the skin’s hydrolipidic film and lipid cement.

Let’s start by putting things into context and looking at how the skin’s lipid cement and the hydrolipidic film actually function in the skin.

The epidermis, the first of the three layers of our skin, acts as a multifunctional barrier between the inside of the body and the outside world. This barrier serves several purposes:

• It acts as a physical barrier, making the skin watertight, firm, and shock-resistant.

• It acts as a filter, protecting the skin from UV radiation.

• It acts as part of the immune system, protecting against infection.

It acts as a moisture barrier, thanks in particular to the skin’s lipid cement and the hydrolipidic film. These combine to prevent moisture evaporation and help maintain optimal skin hydration levels. The latter two components are what we’re interested in today and what we’ll be looking at in more detail in the rest of this article.

This mixture of water and lipids (known as an emulsion) contains:

• Sebum, an oily substance produced by the sebaceous glands. It is secreted through the skin’s pores.

• Sweat, which is made up of water and electrolytes (like sodium, magnesium, and potassium), is also secreted through the pores. Sweat is produced by the sweat glands found in the deeper layers of the skin.

Due to its chemical composition, the film has a somewhat acidic pH, typically between 4.5 and 5. This natural acidity serves several purposes:

• It encourages the desquamation of dead skin cells from the epidermis.

• It inhibits the growth of pathogenic microorganisms.

• It encourages the presence of bacteria that are beneficial to skin health. 

The skin’s lipid cement (or extracellular matrix) binds together the cells of the stratum corneum in the same way that cement binds together the bricks of a house, thereby forming a sealed barrier. It contains:

•  Ceramides. 
• Cholesterol.
• Polyunsaturated fatty acids. 

Because of this composition, the extracellular matrix repels water molecules and inhibits moisture evaporation.

As we age, the production of skin lipids decreases. This weakens the skin barrier and leads to a loss of elasticity and firmness and an increased susceptibility to dehydration.

This phenomenon is exacerbated in women by the menopause, due mainly to hormonal changes, particularly declining estrogen levels. This results in:

• Decreased sebum production, as estrogen plays a crucial role in regulating production of sebum by the sebaceous glands.

• Reduced levels of hyaluronic acid, a substance that helps keep the skin hydrated. Similarly to sebum, estrogen is also linked to the production of hyaluronic acid.

The consequences of this are:

• Increased dehydration, because with reduced levels of sebum and hyaluronic acid, the skin loses its ability to retain water. The symptoms are dry skin, tightness, a dull complexion, and the formation of fine lines.

• Slower cell renewal, which can lead to an accumulation of dead cells on the skin’s surface that give it a rough texture.

A compromised, out-of-balance hydrolipidic film therefore leaves the skin more vulnerable to external aggressors and can also encourage skin conditions like eczema or rosacea. This is why it’s essential to establish a personalized skincare routine that favors moisturizing and nourishing products to help offset this loss of lipids and moisture.

Prevention, like for so many other aspects of the skin, is better than cure. While natural aging is inevitable and requires specific treatments (see below), it is especially important not to damage the skin’s hydrolipidic film and lipid cement.

Any facial cleansing routine should therefore use gentle, non-aggressive methods and accessories. This means avoiding mechanical scrubs using products like horsehair exfoliating gloves and instead opting for exfoliators formulated using fruit acids.

It’s also recommended to use products that respect the skin’s own acidic pH and are rich in lipids and moisturizing active ingredients.

This is why our skin experts recommend our GLOBAL-REPAIR ADVANCED treatments, whose ingredients mimic the natural lipid content of the skin, helping restore the skin barrier. They are inspired by lipid-rich post-procedure treatments used in aesthetic medicine. Laboratoires FILORGA has developed a patented reparative factor that combines several types of lipids to help boost the skin’s natural repair processes.

These treatments come in two forms:

• GLOBAL-REPAIR ADVANCED ELIXIR

  is a serum with a light, oily texture that doesn’t leave the skin feeling greasy. It blends innovative anti-aging active ingredients with precious oils to nourish the skin and target 10 signs of aging (wrinkles, firmness, radiance, texture, elasticity, nutrition, tone, density, evenness, and contours). 

• GLOBAL-REPAIR ADVANCED CREAM

  is an anti-aging face cream with the same properties as the serum. This anti-aging cream is particularly suited to all types of mature skin and features a delicate, soft, enveloping texture for ultimate comfort.