How can I tell if my skin lacks hydration?
Dehydrated skin may feel tight, lack suppleness and show superficial fine lines. It may also appear duller or slightly crepey.
Dehydration is a lack of water in the superficial skin layer. It may be temporary and vary according to the cosmetics used, the season, heating, air conditioning or sun exposure.
Skin that suddenly becomes uncomfortable has therefore not necessarily become dry.
What is the difference between dry and dehydrated skin?
Dry skin mainly lacks lipids, whereas dehydrated skin lacks water.
Dry skin is generally a skin type that produces less sebum. It is often thin, uncomfortable and prone to feeling tight.
Dehydration is a temporary condition that can affect any skin type. Normal, combination or oily skin can therefore be dehydrated.
Skincare is not exactly the same for every skin type.
Can oily skin be dehydrated?
Yes. Oily skin can be dehydrated because sebum production and the amount of water in the skin are two different parameters.
Sebum contributes to the lipid film that protects the skin surface, but is not the water contained in the stratum corneum. Skin can therefore produce a lot of sebum while lacking water.
It may then be shiny while simultaneously feeling tight or showing fine dehydration lines.
Using overly harsh cleansers to reduce sebum can worsen this dehydration by damaging the skin barrier.
How does the skin retain hydration?
The stratum corneum limits the evaporation of water from the skin. Its effectiveness depends, in particular, on intercellular lipids and the natural moisturising factor present in the cells of this layer.
When this barrier functions properly, it limits transepidermal water loss.
Overly harsh cleansing, certain exfoliation, cold weather, very dry air or irritating treatments can disrupt this barrier and increase water loss.
Hydrating the skin properly therefore also means preserving its ability to retain water.
Is drinking plenty of water enough to hydrate the skin?
No. Drinking more water does not replace skincare intended to maintain hydration in the superficial skin layer.
Adequate overall hydration is necessary for normal bodily function. However, drinking several additional litres of water is not enough to correct a damaged skin barrier.
When skin is dehydrated, the priority is to identify what is increasing water loss and adapt the products applied directly to it.
Which cosmetic active ingredients actually hydrate the skin?
Moisturising products generally combine humectants, emollients and occlusive agents.
Humectants, such as glycerine or hyaluronic acid, attract and retain water. Emollients improve the suppleness of the stratum corneum and supplement the lipids between its cells. Occlusives form a barrier that limits water evaporation.
A good moisturiser therefore does more than simply “supply water”. Above all, it should help the skin retain it.
Does hyaluronic acid really hydrate the skin?
Yes. Hyaluronic acid hydrates the skin through its ability to retain water, but its action differs depending on whether it is applied to the skin or injected.
In a serum or cream, hyaluronic acid acts mainly in the superficial skin layers and helps maintain their hydration.
When injected, hyaluronic acid is placed deeper in the tissues and persists there longer. Its action should therefore not be confused with that of hyaluronic acid in a cosmetic product.
Serum or cream: which hydrates better?
Serums and creams do not have the same function in skin hydration and can complement each other.
A serum containing humectants helps retain water in the skin. A cream containing lipids, emollients or occlusive agents limits water loss more effectively and helps maintain the skin barrier.
For dehydrated skin, combining a hydrating serum with a suitable cream may therefore be more useful than applying several serums successively.
For dry skin, cream is particularly important because it supplies the lipids the skin lacks.
Should you apply moisturiser to damp skin?
A moisturiser can be applied to skin that is still slightly damp after cleansing to limit water loss.
The face does not need to be wet. After cleansing, the skin can be gently patted dry, then the cream applied before it dries completely.
This application helps limit water evaporation and restore the skin's protective film.
Why can cleansing dehydrate the skin?
Overly frequent or harsh cleansing can damage skin barrier lipids and increase water loss.
Strongly detergent cleansers, very hot water and repeated cleansing can promote tightness.
Cleansing should remove impurities, make-up and excess sebum without routinely leaving the skin dry or uncomfortable.
A “tight” feeling after every cleanse is not a sign of cleanliness.
Can exfoliants dehydrate the skin?
Yes. Excessive exfoliation can damage the skin barrier and increase water loss.
Exfoliating acids, retinoids and certain scrubs can be useful when appropriately indicated. However, overly frequent use or combining them without care can cause redness, peeling and tightness.
When the skin becomes irritated, it is often preferable to reduce irritating active ingredients temporarily and restore the skin barrier rather than adding new products.
Why does the skin become more dehydrated in winter?
Very hot showers and repeated temperature changes can also worsen this dehydration.
In winter, normally normal or combination skin may therefore need a more protective cream. Dry skin may need a formulation richer in lipids and occlusive agents.
The skincare routine should therefore be adapted to the skin's condition and the season, rather than only to the usual skin type.
Does the sun dehydrate the skin?
Significant sun exposure can damage the skin barrier and promote a feeling of dryness or dehydration.
Sun-exposed skin therefore needs appropriate sun protection and products that preserve its barrier.
In the event of sunburn, the priority is to allow inflammation to subside. Irritating treatments or aesthetic procedures should be postponed until the skin has recovered.
Which aesthetic medicine treatments can improve skin hydration?
Mesotherapy, Skinboosters and certain polynucleotides may be offered when the aim is to improve skin hydration and quality.
Mesotherapy mainly uses non-cross-linked hyaluronic acid, injected superficially through multiple injections with very fine needles. It acts mainly on hydration and radiance.
Skinboosters contain lightly cross-linked hyaluronic acid, injected deeper and designed to persist longer in the tissues. They improve hydration, suppleness and certain superficial fine lines.
Polynucleotides have a different mechanism. They are used to improve skin quality and promote tissue repair mechanisms. However, their evidence base remains less established than that of hyaluronic acid injections.
The choice depends on the condition of the skin and the intended objective.
Can a moisturiser replace these treatments?
A moisturiser remains the basic daily treatment for dehydrated skin, and injections do not replace it.
Cosmetics act mainly on the superficial layer and the skin's barrier function. Injections deposit the product directly into the tissues and serve a different purpose.
How should very dehydrated skin be hydrated?
First, factors that damage the skin barrier should be reduced rather than multiplying moisturising products.
Gentle cleansing, temporarily reducing exfoliants and retinoids in the event of irritation, and regularly using a suitable cream allow the skin barrier to recover.
If dryness is severe, persistent or accompanied by itching, redness or lesions, a skin disorder should be investigated rather than assuming a simple lack of hydration.
Why does my skin remain dehydrated despite using a cream?
A moisturiser may be insufficient if it is not suited to the skin's needs or if the cause of dehydration persists.
Harsh cleansing, overly frequent exfoliation, poorly tolerated retinoids, cold weather, heating or sun exposure can continue to damage the skin barrier despite daily use of a cream.
Persistent dehydration can sometimes be associated with a skin problem requiring medical assessment. Persistent redness, irritation, scaling or itching require medical assessment.
Which routine should you follow to keep skin well hydrated?
An effective moisturising routine should remain simple: gentle cleansing, a suitable moisturising product and daily sun protection; a hydrating serum can be added if necessary.
The choice should primarily take skin type into account. Dry skin generally needs more lipids, whereas dehydrated oily skin may prefer lighter textures.
In Geneva, cold weather, winter heating and seasonal variations can change the skin's needs. The routine should therefore evolve when the skin becomes drier, more uncomfortable or more dehydrated.
Article written by Dr Valeria Romano
Dr Valeria Romano supports each patient through a comprehensive approach to facial, body and intimate aesthetics, as well as skin and hair quality. Every treatment is based on a personalised medical assessment.
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