The best hydrating dermatological active ingredients for the skin

23/04/2026

Des formules élaborées en France à partir d'ingrédients hydratants et testés dermatologiquement

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Camille A.

What hydrating ingredients are good for skin?

Tightness, discomfort, dehydration lines, lack of suppleness... When skin lacks water, it quickly makes itself known. To help it regain comfort, suppleness, and softness, certain hydrating dermatological active ingredients are essential. Among them, four major pillars of hydration stand out: glycerin, urea, hyaluronic acid, and betaine.

In practice, these ingredients help the skin better retain water, regain comfort, and preserve its barrier function. Numerous studies on their efficacy and tolerance have made them benchmark dermatological active ingredients for skin hydration, and their use is widely established in dermo-cosmetics.

In our formulas, glycerin, hyaluronic acid, urea, and betaine are regularly used to support dehydrated skin, dry and rough skin, as well as sensitive or atopic-prone skin.

In this article, we take a closer look at these four benchmark dermatological hydrating active ingredients.

Skin hydration mechanisms

Well-hydrated skin is supple, comfortable, visibly smooth, and better equipped to face daily aggressions. But hydrating the skin is not just about "providing it with water." Skin hydration is based on a subtle balance between several physiological mechanisms¹.

La coupe de peau d'une peau saine et bien hydratée

The skin's ability to retain water

At its various levels, the skin naturally possesses molecules or mechanisms capable of retaining water.
In the stratum corneum, we find the natural moisturizing factor (NMF), a complex made up of different substances such as urea, amino acids, and certain sugars. These molecules act as real water reservoirs, helping the skin maintain good hydration levels and preserve its suppleness.
In the epidermis, water is captured by cells called keratinocytes. By regulating their osmolarity, keratinocytes maintain their hydration: they facilitate the entry and exit of water through their cell membranes via specialized channels called aquaporins².
In the dermis, the extracellular matrix is rich in GAGs (glycosaminoglycans), including hyaluronic acid, which retain water like sponges.

Coupe de peau illustrant la perte insensible en eau

The skin's ability to limit water loss

The skin continuously loses a tiny amount of water through a natural phenomenon called transepidermal water loss (TEWL). When the skin barrier is compromised (due to various factors such as cold, wind, repeated washing, or certain skin sensitivities), this transepidermal water loss can increase and lead to skin dehydration.

To reduce water loss, the stratum corneum has an intercellular lipidic cement whose hydrophobic fatty substances (ceramides, cholesterol, fatty acids) help maintain the integrity of the skin barrier and limit water evaporation.

The skin's ability to adapt to its environment

Various external and individual factors influence the skin's moisture balance:

Climate and environment (cold, wind, dry air),
Age,
Skincare habits,
Or even the skin's natural sensitivity.

When this balance is disrupted, the skin becomes dehydrated and may show characteristic signs such as discomfort, decreased suppleness, a less radiant complexion, or dehydration fine lines. On the body, the skin may feel tight. To properly moisturize your body, discover our dedicated article.

Dehydration can affect all skin types: dry skin, but also normal, combination to oily, and oily skin. To address this, hydrating dermatological active ingredients have proven effective.

What are the most effective hydrating dermatological active ingredients?

Glycerin: an essential moisturizing active ingredient

You're probably familiar with it... Glycerin (or glycerol) is one of the classic ingredients in moisturizing dermo-cosmetics. It's so widely used because it helps the skin attract and retain water in the upper layers of the epidermis, thus helping to restore suppleness and comfort to the skin ³ ⁴.

Glycerin is a humectant, meaning an active ingredient capable of capturing and retaining moisture, thanks to its chemical structure which allows it to form strong bonds with water molecules.

Glycerin can be obtained through several processes. In dermo-cosmetics, plant-based glycerin is predominantly used, obtained from vegetable oils (soy, rapeseed, palm, coconut).

Thanks to its excellent tolerance, glycerin is among the moisturizing ingredients recommended by dermatologists. It is particularly suitable for normal, dehydrated, sensitive, reactive, atopic skin, and even the delicate skin of infants. And more broadly, for all skin types seeking effective and well-tolerated daily hydration.

Urea: moisturizing and exfoliating active ingredient

Urea has a special status in dermatology because it is a natural component of the skin: it is found in the natural moisturizing factor (NMF), this set of molecules involved in maintaining water in the epidermis. It is a so-called biomimetic molecule, capable of mimicking the benefits of urea naturally present in cutaneous NMF⁵.

Depending on its concentration, urea can meet several skin needs⁶ ⁷:

Between 2 and 5%, it is ideal for daily hydration of dehydrated and slightly dry skin because it acts as a humectant by retaining water.
Between 5 and 10%, it moisturizes and provides a light smoothing effect for more suppleness, comfort and softness.
Between 10 and 20%, urea combines its moisturizing action with an exfoliating effect that helps improve the appearance of roughness, soften thickened areas and even out the skin's texture.
Beyond 20%, urea can be indicated in cases of hyperkeratosis requiring greater keratolytic action.

The urea used in dermo-cosmetic products is obtained by a controlled synthesis process, making it possible to reproduce a molecule identical to that of the skin, with a high level of purity and safety. This controlled origin guarantees excellent tolerance and perfect affinity with the skin.

With its moisturizing and exfoliating properties and its harmlessness, urea is therefore an ideal moisturizing active ingredient for dry and rough skin, or thickened skin (such as on the knees, elbows, and heels) and looking for comfort.

Hyaluronic acid: a hydrating anti-aging active ingredient

Hyaluronic acid is now one of the most emblematic active ingredients in hydrating dermo-cosmetics. Naturally present in the skin, it plays an essential role in maintaining its hydration and suppleness.
When used in skincare, it helps to attract and retain water in the superficial layers of the epidermis, thereby contributing to more comfortable, supple, and visibly smoother skin ⁸ ⁹.

Hyaluronic acid is a powerful humectant, capable of binding up to 1000 times its weight in water⁸ thanks to its long polysaccharide chain structure. It thus forms a true reservoir of hydration on the skin's surface.

In dermocosmetics, hyaluronic acid is used in different molecular weights (size of its molecule), which determine its mode of action⁸

High molecular weight hyaluronic acid acts on the surface, in the stratum corneum and epidermis, and helps limit water loss while providing an immediate smoothing effect.
Low molecular weight hyaluronic acid penetrates into the dermis, where it contributes to good hydration as well as stimulating collagen synthesis, combining its moisturizing effect with plumping anti-aging benefits.

The hyaluronic acid used in cosmetics is obtained by a biotechnological fermentation process, allowing the production of a highly purified, stable, and well-tolerated molecule, identical to that naturally present in the skin. This natural affinity explains its excellent tolerance.

It is particularly suitable for dehydrated, sensitive, or uncomfortable skin, as well as for skin that wishes to preserve its suppleness and smooth appearance over time. More broadly, it can easily be integrated into all routines to support daily hydration and contribute to visibly plumper skin.

Find out all about the moisturizing properties of hyaluronic acid in our dedicated article.

Betaine: a hydrating and soothing active ingredient

Less well-known than glycerine or hyaluronic acid, betaine is nonetheless an interesting dermo-cosmetic hydrating active ingredient, particularly for its ability to help the skin maintain its moisture balance while contributing to improving its comfort⁴ ¹⁰.

In the skin, betaine is an osmolyte, meaning a molecule capable of regulating water balance within cells. Thanks to its specific chemical structure, it helps to retain water in the stratum corneum and protect skin cells against variations in their environment (cold, dryness, skin stress).
It thus acts as a hydration regulator, supporting the skin's natural mechanisms. This action helps to limit feelings of discomfort, improve skin suppleness and promote softer skin to the touch.
Beyond its hydrating role, betaine is also recognized for its soothing properties, particularly suitable for sensitive skin or skin prone to discomfort.

The betaine used in cosmetics is mainly of plant origin, obtained from sugar beet. It is then purified to guarantee good tolerance and consistent quality, suitable for sensitive skin care products.
It is precisely its gentleness that makes it a hydrating active ingredient recommended by dermatologists. It is suitable for dry, sensitive or atopic-prone skin, as well as weakened skin or skin prone to discomfort. More broadly, it fits perfectly into hydrating routines to reinforce daily skin comfort, in addition to other humectant active ingredients.

Why combine several moisturizing ingredients?

Glycerin, urea, hyaluronic acid, and betaine are among the essential dermatological active ingredients for hydration. Each has its specific properties, but all contribute to good skin hydration by helping it retain water better, preserve its comfort, and support its skin barrier.

Moisturizing active ingredients in TOPICREM skincare

At TOPICREM, we use them in our various ranges according to their different properties:

Glycerin is present in the majority of our face and body care products.
Hyaluronic acid is the key active ingredient in our AH3 range dedicated to mature skin.
Urea contributes to the moisturizing effectiveness of the ULTRA MOISTURIZING and DERMO SPECIFIC body ranges.
Betaine takes care of the hydration of dehydrated and sensitive skin within the HYDRA+ range.

When well-formulated and combined, these moisturizing active ingredients, approved and recommended by dermatologists, can effectively support dehydrated, dry, sensitive, or rough skin daily¹¹.

Dermatological expertise for hydration

TOPICREM formulas are all designed to provide protective hydration and preserve the skin barrier of sensitive skin for the whole family.

To achieve this, the laboratory relies on its expertise derived from pharmaceutical excellence:

Selection of high-tolerance ingredients with proven efficacy,
Development of formulas clinically tested on sensitive skin,
Efficacy demonstrated by science and approved by consumers.

Through the comfort and emotional well-being they provide, our skincare products help you feel confident in your skin and in yourself, to better reveal yourself to others, and thus fully enjoy every moment of life.

References:

¹Verdier-Sévrain S, Bonté F. Skin hydration: a review on its molecular mechanisms. J Cosmet Dermatol. 2007 Jun;6(2):75-82. doi: 10.1111/j.1473-2165.2007.00300.x. PMID: 17524122.

²Draelos Z. Aquaporins: an introduction to a key factor in the mechanism of skin hydration. J Clin Aesthet Dermatol. 2012 Jul;5(7):53-6. PMID: 22798977; PMCID: PMC3396453.

³Becker LC, Bergfeld WF, Belsito DV, et al. Safety Assessment of Glycerin as Used in Cosmetics. International Journal of Toxicology. 2019;38(3_suppl):6S-22S. doi:10.1177/1091581819883820

⁴Björklund S, Engblom J, Thuresson K, Sparr E. Glycerol and urea can be used to increase skin permeability in reduced hydration conditions. Eur J Pharm Sci. 2013 Dec 18;50(5):638-45. doi: 10.1016/j.ejps.2013.04.022. Epub 2013 May 3. PMID: 23643739.

⁵Piquero-Casals J, Morgado-Carrasco D, Granger C, Trullàs C, Jesús-Silva A, Krutmann J. Urea in Dermatology: A Review of its Emollient, Moisturizing, Keratolytic, Skin Barrier Enhancing and Antimicrobial Properties. Dermatol Ther (Heidelb). 2021 Dec;11(6):1905-1915. doi: 10.1007/s13555-021-00611-y. Epub 2021 Oct 1. PMID: 34596890; PMCID: PMC8611129.

⁶Dall'Oglio F, Tedeschi A, Verzì AE, Lacarrubba F, Micali G. Clinical evidences of urea at medium concentration. Int J Clin Pract. 2020 Dec;74 Suppl 187:e13815. doi: 10.1111/ijcp.13815. PMID: 33249708.

⁷Celleno L. Topical urea in skincare: A review. Dermatologic Therapy. 2018;31:e12690. https://doi.org/10.1111/dth.12690

⁸Bravo B, Correia P, Gonçalves Junior JE, Sant'Anna B, Kerob D. Benefits of topical hyaluronic acid for skin quality and signs of skin aging: From literature review to clinical evidence. Dermatol Ther. 2022 Dec;35(12):e15903. doi: 10.1111/dth.15903. Epub 2022 Oct 21. PMID: 36200921; PMCID: PMC10078143.

⁹Karabat MU, Tuncer MC. Effects of hyaluronic acid on skin at the cellular level: a systematic review. Rev Assoc Med Bras (1992). 2025 Sep 19;71(8):e20250208. doi: 10.1590/1806-9282.20250208. PMID: 40990743; PMCID: PMC12452154.

¹⁰Burnett CL, Bergfeld WF, Belsito DV, et al. Safety Assessment of Alkyl Betaines as Used in Cosmetics. International Journal of Toxicology. 2018;37(1_suppl):28S-46S. doi:10.1177/1091581818773354

¹¹Alvarez G, Kang B, Richmond A ... Skincare ingredients recommended by cosmetic dermatologists: A Delphi consensus study. Journal of the American Academy of Dermatology, 2025; 93, 1509-1525