How to moisturize your skin - the complete guide by a doctor and analyses by BeautyDecoders.
Three families of agents combined: a humectant to attract water, an emollient to repair the barrier, and an occlusive to retain it. The order goes from the most fluid to the richest, and skincare is chosen according to skin type - not according to the number of products.
Hydration, base healthy skin
The stratum corneum acts like a shield: corneocytes linked by a lipid cement that limits water evaporation and repels aggression. A lack of hydration weakens this barrier - the skin dries out, becomes dull and more vulnerable to redness.
We need to distinguish between two conditions that are often confused. A dry skin is a type of skin that produces little lipid: it lacks oil, durably. A dehydrated skin water deficiency can affect any skin type, including oily skin. In all cases, providing water through appropriate skin care preserves the skin's barrier function and improves comfort.
To situate this step in the overall routine, see the guide facial care.
How the skin retains water
Internal contribution
Water comes from the bloodstream and reaches the dermis, a veritable reservoir, which then distributes it to the epidermis. Staying hydrated from within feeds these reserves.
Fixation in the epidermis
Natural moisturizing factors (amino acids, urea, sugars) are hygroscopic: they act like sponges, trapping moisture in the stratum corneum.
Evaporation control
The surface hydrolipidic film, combined with the lipid cement of the stratum corneum, slows down insensible water loss. Keeping this film in good condition is essential.
Moisturizers aim precisely to support these three mechanisms: supplying water, retaining it in the epidermis, and reinforcing the lipid barrier. This is why a humectant alone is not enough - the water it attracts evaporates if nothing seals it in.
Humectants, emollients, occlusives
| Family | Role | Examples |
|---|---|---|
| Humectants | Attract water and plump the epidermis, like sponges | Glycerin, hyaluronic acid, urea, lactic acid, aloe vera |
| Emollients | Fills gaps between corneocytes, repairs the barrier | Ceramides, squalane, vegetable oils, triglycerides |
| Occlusive | Hydrophobic surface barrier reduces water loss | Petrolatum, shea butter, waxes, dimethicone |
The effectiveness of occlusives varies widely. The literature shows that petrolatum (petroleum jelly) is the reference occlusive At a minimum of 5 %, it reduces insensible water loss by over 98 %, whereas mineral oils, lanolin or silicones such as dimethicone only reduce it by 20 to 30 %. This moderation makes dimethicone, in small quantities, an interesting occlusive for combination to oily skin: it seals in moisture without an overly occlusive effect. Some emollients are also occlusives - so the same ingredient can appear in several categories.
In which order applying care
The principle: humectants first draw water into the epidermis, then seal it in with emollients and occlusives. From the most fluid to the richest.
1. Cleaner - on clean skin, skincare products penetrate better. 2. Lotion or mist (optional) - first moisturizing layer, alcohol-free. 3. Moisturizing serum - on slightly damp skin, rich in humectants (hyaluronic acid, glycerine). 4. Moisturizing cream - light for oily skin, richer for dry skin; seals in moisture. 5. Oil or balm (if necessary) - occlusive layer to prevent night-time dryness. 6. Sun protection (morning) - essential, UV exposure dehydrates.
Moisturize with skin type
| Skin type | Recommended textures | Points of attention |
|---|---|---|
| Dry skin | Rich formulas: butters, vegetable oils, ceramides; serum + cream + balm layering | Avoid aggressive cleaning agents and hot water. |
| Combination skin | Light, non-comedogenic cream; more on the cheeks, less on the T-zone | Cleanse gently to avoid dehydrating dry areas. |
| Oily skin | Light gels and fluids, rich in humectants, non-comedogenic | Moisture deprivation increases sebum production (rebound effect). |
| Sensitive skin | Short, fragrance- and alcohol-free formulas; ceramides, panthenol, soothing agents | Introduce new products gradually. |
The best moisturizers by skin type
A selection of the best-rated products on the BeautyDecoded app, with compatibility scores and review summaries. The Sensitivity Verdict applies the Dr David Rule: a sensitive skin score below 0 indicates a potential risk of irritation; between -2 and -5, a product that is not suitable for sensitive skin.
Anua Heartleaf 77% Soothing Toner
Universal profile - first layer
Toning lotion with 77 % of Houttuynia cordata (heartleaf) extract, to be applied after cleansing as a first layer of hydration. Sensitive skin score +1.5 - very well tolerated, including reactive skin. Universal profile (84 to 91 on all skin types). Light, fragrance-free texture prepares skin to receive serums.
The Ordinary Soothing & Barrier Support Serum
Barrier support under active irritants
Soothing, barrier-repairing serum, ideal to accompany irritating active ingredients such as retinol or AHAs. Sensitive skin score 0 - suitable. Versatile profile covering all skin types. Feedback describes it as a reliable support for the skin barrier, with a slight sticky effect for some.
Hada Labo Gokujyun Premium Hyaluronic Acid Lotion
Highly moisturizing - thick texture
Japanese moisturizing lotion concentrated in several hyaluronic acids. Sensitive skin score -0.6 - slight caution. Highly moisturizing profile suitable for all skin types (84 to 91). Thick, slightly sticky texture according to feedback, better tolerated in the evening than during the day for certain profiles.
Byoma Moisturizing Gel-cream
Optimal profile for combination to oily skin
Lightweight, ceramide-based gel-cream for combination to oily skin. Sensitive skin score +0.85 - well tolerated. Normal to oily skin score 91 - optimal profile for this need. Moisturizes while regulating sebum, with some discomfort on very reactive skin.
CeraVe Moisturizing Balm
Dry skin - too rich for oily skin
Rich balm with ceramides and hyaluronic acid for dry to very dry skin. Sensitive skin score +0.6 - adapted. Profile geared towards dry skin (91), not suitable for oily skin (0). Several feedbacks point out that it is too rich for the face and better tolerated on the body: to be reserved for really dry skin.
Eucerin Aquaphor Repair Balm
Targeted areas - comedogenic on the face
Petrolatum occlusive balm for very dry areas, chapped lips and damaged skin. Sensitive skin score +2.25 - very well tolerated. Petrolatum, the most effective occlusive (water loss reduction greater than 98 %). To be reserved for targeted dry areas: several reports indicate that it can comedogenicize the face.
Aroma-Zone Aloe Vera Native Gel
Economical humectant - minimalist routine
Native aloe vera gel, a light, economical humectant for a minimalist routine. Sensitive skin score +1.0 - well tolerated. Use as a first moisturizing layer, ideally followed by an oil or cream to seal in the water. Versatile for face and hair, according to feedback.
Depending on age and season, zones
Age. The older we get, the drier our skin becomes: formulas rich in ceramides, fatty acids and antioxidants are suitable for mature skin, while a light gel is often sufficient for young adults. Season. In winter, when it's cold and the air from the heating is dry, you need richer creams; in summer, you need fluid textures to avoid the «suffocating skin» effect. Zones. Lips and eye contour are very sensitive: use a balm on the lips several times a day, and a specific ophthalmologically-tested, fragrance-free product for the eye contour area.
Properly moisturized skin is more resistant, softer and more radiant. It is better able to withstand powerful active ingredients (retinol, exfoliating acids, vitamin C) which, without proper hydration, can irritate or sensitize the skin.
Your questions about hydration
What's the difference between dry and dehydrated skin?
Is it necessary to moisturize oily skin?
In what order should you apply your moisturizers?
Is hyaluronic acid the best moisturizer?
Does drinking lots of water moisturize the skin?
Our guides hydration detailed
Moisturizing cream for oily skin
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Comparison
Moisturizing cream for dry skin
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Comparison
Moisturizing cream for sensitive skin
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Comparison
Moisturizing cream for normal to combination skin
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Comparison
Best moisturizing lotions
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Comparison
Best moisturizing serums
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Comparison
Best moisturizers
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Decoding
Is hyaluronic acid the best?
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Plastic and aesthetic surgeon - Founder of BeautyDecoded
Information for educational purposes only. It does not replace a medical consultation and must be adapted to each individual. The compatibility scores generated by the application do not prejudge the individual tolerance of each skin type. In the event of pregnancy, skin pathology or doubt, dermatological advice is recommended. A tolerance test should be carried out before using the product for the first time.