I have DE(-) skin – what does this mean?

Skin ageing: BEGINNER ("Débutant" in French)

Oxidation factors: EXPOSED

Sebum production: LOW (-)

The letter “D” indicates that the skin is entering the first visible stages of cutaneous ageing. Expression lines appear when the skin is in motion, particularly around the eyes and mouth, and become the first discernible signs of tissue laxity. These lines are often accompanied by a change in skin texture, a less even complexion and a gradual loss of radiance. Such manifestations reflect the initial biological slowdowns within the various layers of the skin, generally observable by the late twenties.

From that age, the production of collagen, an essential protein for dermal cohesion and firmness, decreases by approximately 1% per year. This gradual decline disrupts the extracellular matrix and weakens the density of the connective tissue. At the same time, epidermal cell turnover slows down, which impairs the barrier function, increases transepidermal water loss, and thereby intensifies fine lines. Finally, the synthesis of hyaluronic acid, a molecule naturally present in the skin that can hold up to 1,000 times its weight in water, decreases on average by 6% per decade, contributing to the loss of skin suppleness and resilience.

The ageing of DE(-) skin remains superficial and primarily functional: the skin still retains a good capacity for recovery. However, implementing a suitable skincare routine can slow this transition phase and help maintain a more youthful appearance over time.

The "E" indicates that the skin is heavily exposed to external stressors (solar radiation, atmospheric pollution, tobacco, stress, alcohol...), and that its sun-protection habits are insufficient relative to its phototype and its exposure rhythm. These oxidative factors promote the production of free radicals, highly unstable and reactive molecules that can have a long-lasting impact on the skin. Note that the production of free radicals is a normal process in all oxygen-consuming living organisms. They have an endogenous antioxidant defence system that keeps the quantity of generated free radicals under control.

However, in the event of an imbalance between the production of free radicals and the body's capacity to neutralise them, a situation of oxidative stress sets in and skin damage may occur. Indeed, free radicals are reactive species that contribute to the degeneration of skin cells, both at the epidermal and dermal levels. All of the skin's vital components, such as collagen, hyaluronic acid, elastin, lipids and DNA, are attacked, resulting in various dysfunctions. This oxidation process can affect the structure of the skin, accelerate its ageing, and even increase the risk of cancer. Wrinkles, initially superficial and then progressively deeper, a loss of firmness and a duller complexion can begin to appear, and this often occurs prematurely.

The “-” indicates a reduced efficacy of the sebaceous glands in producing sufficient sebum to protect the skin, as well as an abnormality in the synthesis of natural moisturising factors by keratinocytes. These hygroscopic molecules (amino acids, lactates, urea, mineral ions...) normally ensure water retention within the stratum corneum. Tightness, irritation, dehydration fine lines, redness, flaking, dull complexion... are characteristic of this skin type.

Indeed, this lack of lipids reduces the efficiency of the hydrolipidic film and increases water loss. This alteration of the skin barrier can also disrupt the activity of Langerhans cells, the immune sentinel cells of the epidermis, sometimes triggering an excessive inflammatory response to stimuli that are normally harmless. Several factors can influence the low sebum secretion in DE(-) skin, such as frequent washing, certain drug treatments, unsuitable skincare, seasonal variations, smoking, UV radiation or even genetics.

DE(-) skin exhibits two primary vulnerabilities: considerable exposure to oxidative stressors and insufficient sebum production. To address these shortcomings, we recommend the following skincare routine.

In the morning, the priority is to prepare the skin to face external aggressions whilst providing it with hydration and nourishment. After a gentle cleanse, for instance with a tonic lotion, we advise DE(-) skin types to use a antioxidant serum. Active ingredients such as vitamin C, the resveratrol, or even ferulic acid help to neutralise the free radicals generated by pollution and UV. Next, to restore the hydrolipidic film, it is important to use an emollient cream containing, for example, squalane, naturally found in sebum, or ceramides, found in the stratum corneum. These physiological lipids contribute to restoring the skin barrier and limit transepidermal water loss. Finally, do not forget sun protection, even on cloudy days, to reduce oxidative stress induced by UVA and UVB rays.

In the evening, the skin enters a phase of active cellular regeneration : it's time to supply it with reparative and relipidating active ingredients. After a gentle cleanse, for example with a superfatted soap or a cleansing balm, applying a hydrating serum based on hyaluronic acid helps retain water in the stratum corneum. You can then follow up with a relipidating serum, formulated from squalane or a biomimetic complex, to reinforce the skin barrier and soothe sensations of tightness. To seal in hydration and nourish the epidermis over the long term, simply apply a rich-textured moisturiser.