Shelves of products for dry skin are packed with dozens of active ingredients today – from vitamins and ceramides to hyaluronic acid. But they do not all work in the same way. We explain where skin dryness comes from and which ingredients genuinely help to hydrate and repair it.

Where does skin dryness come from?

Dry skin is the result of a disrupted water–lipid balance in the epidermis. The stratum corneum, the outermost layer of the skin, is made up of cells (corneocytes) surrounded by a lipid “cement” consisting mainly of ceramides, cholesterol and free fatty acids. This structure is often compared to a brick wall: bricks (corneocytes) held together by mortar (lipids) – when the mortar is missing, the wall no longer protects what lies behind it.

When this lipid cement is weakened – due to genetics, age, environmental factors or overly aggressive skincare – the protective barrier stops retaining water effectively, transepidermal water loss (TEWL) increases, and the skin becomes dry, rough and more prone to irritation [1,2]. A weakened barrier also lets irritants and allergens from the environment through more easily, which can aggravate inflammation and skin discomfort.

Does dry skin lack vitamins?

Skin dryness rarely results solely from a vitamin deficiency – more often it is caused by a weakened lipid barrier and a shortage of natural moisturising factors (NMF). Nevertheless, some vitamins play an important role in supporting proper skin function: vitamin E acts as an antioxidant and supports skin elasticity, vitamin A (retinol and its derivatives) regulates epidermal renewal, and vitamin B5 (panthenol) has well-documented moisturising and soothing properties. That is why products for dry skin often combine vitamins with other hydrating ingredients.

Which ingredients support dry skin?

The most effective care for dry skin combines three groups of ingredients: humectants (which bind water), occlusives (which prevent water loss) and emollients (which soften and smooth the epidermis). The best-researched hydrating ingredients include hyaluronic acid, ceramides, urea, glycerin, trehalose and PCA (amino acid derivatives naturally present in the epidermis as part of the natural moisturising factor). All of these can be found in the formulas of the Hydrain line, developed for dry and dehydrated skin – the more of these groups a product combines, the more comprehensively it supports the repair of the protective barrier.

How does a moisturiser with ceramides work?

Ceramides are lipids that occur naturally in the stratum corneum and are responsible for its tightness. A moisturiser with ceramides replenishes their deficiency, rebuilding the structure of the protective barrier and limiting water loss [3,4]. The effect is noticeable not only in instrumental measurements, but also in everyday skin comfort – less tightness and roughness. Ceramide NG is found, among others, in the Hydrain Night Cream and the Hydrain Hydrating Serum for Face, Neck and Décolletage – in a clinical study, the night cream reduced transepidermal water loss (TEWL) by 27% after 4 weeks of use.

How does a moisturiser with hyaluronic acid work?

Hyaluronic acid is one of the most effective humectants – it can bind many times its own weight in water. Cosmetics use hyaluronic acid of different molecular weights: high-molecular-weight forms work on the skin’s surface, creating a film that holds water in, while low-molecular-weight forms penetrate deeper and hydrate the epidermis from within [5,6]. Combining both fractions, as in the Hydrain Moisturizing Physiotoner or the Hydrain Under-Eye Cream, provides comprehensive hydration – both on the surface and in the deeper layers of the epidermis.

Dry skin, diet and lifestyle

The condition of your skin depends not only on external care, but also on what happens “on the inside”. A diet rich in unsaturated fatty acids (e.g. from oily sea fish, flaxseed oil and nuts) supports the proper function of the skin’s lipid barrier, and adequate hydration remains a good complement to skincare, although according to research its effect on skin hydration is more limited than commonly believed [7]. Chronic stress, lack of sleep and long periods spent in dry, heated or air-conditioned air also have a negative impact on the skin.

Which vitamins for dry skin? Will supplements help?

With a well-balanced diet, extra vitamin supplements are usually not necessary to improve skin hydration. The exception is when blood tests confirm a genuine deficiency – e.g. of vitamin D or omega-3 fatty acids – in which case it is worth discussing supplementation with a doctor rather than taking products “by guesswork”. The effects of supplementation, even when it is needed, only become visible after many weeks, because the body first replenishes deficiencies in the internal organs and only later in the skin.

In everyday care, topical hydrating products remain more effective than dietary supplements, because they act directly on the skin and their effects – greater comfort, less tightness, smoother skin – can be assessed much sooner, usually after just a few days of regular use. The best results come from combining both approaches: a balanced diet that supports the body from within, and dermocosmetics with proven hydrating effects, used every day.

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