What is Urea and its Benefits in Skin Care?

What is Urea? Chemical Structure of Urea

It often happens in the search for new therapeutic agents that some old stand-by has been overlooked, whose luster has worn off, but which may have useful application in moments when the miracle drugs falter. In the world of topical therapy, urea is such a drug. Youthful skin with a visible glow – it’s the holy grail of skin care. 

Albert Kligman

So, what if I told you the key to super-healthy skin is hydration?

Dehydrated skin causes horizontal lines to appear; the types of lines that lead to deep-seated wrinkles, especially if not treated correctly. That’s right; something as simple as keeping your skin plump and moist can ward off premature ageing for many years to come

But, shhh! There is one little “beauty secret” that not too many people know and that secret is Urea – which is, in my opinion, one of the most effective moisturising ingredients in cosmetic chemistry. Urea’s role within the skin is remarkable; it maintains a healthy moisture balance, bringing much-needed relief to dry skin, whilst keeping it soft, supple, and youthful.

It seems ironic to think that as far back as 1957, urea was viewed as an old, forgotten therapy despite being rediscovered by Dr Kligman, the man behind Retin A. And yet, even today there is very little information about what could be considered the holy grail of the skincare world.

So, What Is Urea?

Urea is a humectant, referred to as Hydroxyethyl Urea – not to be confused with the preservatives Imidazolidinyl Urea and Diazolidinyl Urea, which I discuss in more detail below.

Urea is a naturally-occurring substance found in the surface layer of our skin, and is an active part of our natural moisturising factor (NMF), which functions to keep skin hydrated, protected, and working efficiently.

It is made up of 40% amino acids, 12% sodium PCA, 9% glycerol, and 8.5% urea – all of which are water-binding (hygroscopic) components essential for maintaining the health, function, and hydration of the stratum corneum.

Healthy skin typically contains 28 micrograms of urea per square centimeter. Those with dehydrated and dry skin can see an improvement in their symptoms of as much as 50%, and in those with eczema, as much as 80%. There is evidence to suggest that urea helps treat ichthyosis, dermatitis, psoriasis, xerosis, and even nail fungus.

The Sciency Skin Bit

In order to understand how urea works, it is important to understand the skin’s structure.

Your outermost layer of the epidermis – the stratum corneum – is made up of corneocytes and an inter-cellular cement which has a high resistance to many chemical agents. Inside the corneocytes is our natural moisturising factor (NMF) – a mixture of substances that regulate the level of moisture on our skin’s surface by binding water molecules.

Urea is a natural component of our skin’s tissues and makes up 7% of our natural moisturising factor, which decreases with age.

Whilst applications of emollient and occlusive ingredients coat the skin’s surface to create instant moisturisation, it is only a temporary fix, which won’t improve the skin’s ability to create and hold water the way urea does. When it is applied to the skin, urea penetrates the stratum corneum, where it readily absorbs and retains water; increasing the capacity of the skin to hold moisture and rehydrate.

To conclude, it helps to regulate the cell cycle; encouraging natural desquamation or exfoliation, enhancing your barrier function, and regulating the good micro-flora that reside on your skin to keep your protective acid mantle intact.

“Urea appears to be a highly-active small molecule regulator of genes that impact keratinocyte differentiation, lipid synthesis and antimicrobial peptide production, together leading to improved permeability barrier function and likely antimicrobial defense as well.” (1)

Dry Skin Connection

Dry skin results from a lack of oil and water in the outer layer of skin, the epidermis. Skin becomes scaly, cracked, and itchy.

Moisture is normally retained in the epidermis by a surface film of oils (sebum), broken-down skin cells, and natural water-holding substances. Urea is one of these water-holding substances, the others being lactic and amino acids. We know reduced levels of urea leads to a lower water-binding capacity within the skin, which in turn leads to roughness, tightness, flaking, and irritation.

Research has found a link between severe dry skin conditions – such as ichthyosis, seborrheic dermatitis, psoriasis, eczema, and even nail fungus – and drastically reduced amounts of urea in the stratum corneum.

Urea stimulates the components of the skin that keep it healthy, which is referred to as epidermal gene expression. When applied, it increases the formation of filaggrin; an important protein found within the skin that keeps everything balanced. It also maintains the barrier function by building up your skin’s defence mechanisms.

Urea’s Skin-Loving Benefits

Hydrophilic

Meaning “water-loving”, this property gives urea its amazing ability to hold onto water molecules, keeping our skin moist.

Not only does it readily absorb water, but it also has a very high water content, which helps to reduce the amount of water lost through the skin.

On a molecular level, urea modifies the structure of amino chains and polypeptides within the skin, which is important for helping to moisturise our delicate tissues.

Research has found a direct correlation between our skin’s water content and its levels of amino acids. Basically, the more dehydrated and dry the skin is, the lower its share of dissolved amino acids.

To learn more about the damaging effects of dehydrated skin, follow the link.

Improves Barrier Function

One of the many ways urea benefits our skin is by helping to accelerate the cellular renewal process. The really great thing about this is that it strengthens the barrier function of the skin, helping to keep it youthful and healthy.

In the article, “Understanding the Acid Mantle“, I discuss the importance of having a strong barrier function and how it creates a stronger resistance against potential irritants.

Natural Exfoliant

Urea has powerful keratolytic properties that, combined with its hydrating properties, make it a potent moisturising and exfoliating treatment for the skin. It works in synergy with ingredients that create the molecular structure of healthy skin, such as lactic acid, helping other ingredients penetrate deeper.

Combined, these two ingredients actively work to remove dead skin cells and substances from the skin’s horny layer; improving cellular turnover in the epidermis and helping to dramatically improve the water-binding ability of the skin, literally REBUILDING HEALTHY SKIN from the inside out.

Fights Acne

Urea further improves skin health by metabolising the antimicrobial peptide LL-37, which literally kills the acne-causing bacteria within the skin. An in vitro study also indicates that urea directly inhibits the yeast malassezia, which is often the cause of fungal acne.

Possible Anesthetic

Urea has another interesting profile; it can create a local anaesthetic effect on the skin and has anti-itch properties.

This is really useful in helping to reduce cycles of inflammation and flare-ups, making it my product of choice for sensitive skin conditions.

Penetration

Studies have found that urea plays a key role in increasing the permeability of certain skin care ingredients, working as a vehicle for other performance ingredients by encouraging them to penetrate the epidermis easily.

Natural Moisturiser

Dry skin is often due to a reduction of urea in the skin’s delicate tissues, leading to tightness and flakiness. Because urea is a natural moisturising factor, it can offer instant relief to dry skin.

I include urea in H₂O Hydrating Complex to help hydrate and repair skin cells.

The gentle exfoliating action of urea helps to leave the skin super smooth, especially when layered; the texture of the skin is visibly softer, giving it a youthful glow. I have seen some great results from urea on my clients who suffer from extremely dry and dehydrated skin.

Urea’s Best Bits

Phew! With so many beautifying properties, where do you begin?

For the benefit of those who require a little recap, here are this cool little ingredient’s best bits:

  • Urea is naturally produced by our skin
  • It regulates our skin’s moisture content and is an essential component of our Natural Moisturising Factor (NMF)
  • Urea is hygroscopic, which means it is able to bind moisture on to the outermost layer of our skin
  • The perfect treatment for dry skin, it has anti-itch and anti-microbial properties
  • It can kill the bacteria cause acne
  • It is also keratolytic, meaning it breaks down the connections between dead skin cells; naturally exfoliating the skin and helping ingredients penetrate further

Percentages used in skin care

  • Less than 10% in a formula helps with water retention in the skin, helping to bind moisture onto the skin. This is due to its extremely hydrophilic nature, making it a popular choice for its moisturising effect.
  • Over 10% urea has a light keratolytic effect, making it a great choice for those with dry, flaky skin that requires an extra boost. At this percentage, it creates an exfoliating product that won’t scratch the skin, perfect for those with conditions such as eczema.
  • At higher doses of around 30-40%, its strong keratolytic properties make it great for more serious therapeutic uses, such as treating psoriasis.

The Naked Truth

Urea is often referred to as Carbamide, the primary organic solid of urine, which is waste that has been produced by the body after it metabolises protein.

Thankfully, the urea used in the cosmetic industry is made from synthetic sources and is not animal-derived. It is formed from ammonia and carbon dioxide, and can be produced in either a solid or liquid form.

There are three forms of urea found in personal care products: Hydroxyethyl Urea, Diazolidinyl Urea, and Imidazolidinyl Urea. People often get confused by these, but they are, in fact, completely different ingredients.

Diazolidinyl and Imidazolidinyl Urea are antimicrobial preservatives used in the skincare industry to protect personal care products from bacteria, yeast, and mold. They do get a lot of bad press as a preservative due to the fact that they are proven to release formaldehyde. Hydrovance (INCI name “Hydroxyethyl Urea”) is a potent humectant and considered safe as a cosmetic ingredient.

I do hope I have gone some way to answer your questions on what urea is. I appreciate that dry skin is a really frustrating skin type to treat, simply because it causes so many conditions within the skin:

  • Dehydration due to a lack of water
  • A lack of a protein called Fillagrin
  • Dryness due to a reduction in ceramides and moisturising lipids 

247 thoughts on “What is Urea and its Benefits in Skin Care?

  1. raveena says:

    Hi Samantha
    Can you please advice me on the usage amount of urea? I am trying to formulate foot cream for my mum who is quite old and also to keep our feet moisturized and supple.
    What sort of urea should I be buying as you mentioned it is also used as a preservative. Can I combine it with Salicylic acid?
    Should I use the suppliers recommended amount as I have seen formulations that are using 20-40percent pure urea.
    Thanks in advance.

      • Ruth says:

        Hello Samantha,

        I enjoyed your article very much. I think urea is something I need to try ext.
        I’m trying to find something to heal my lips and outer lip area.
        I am prone to cold sores especially with sun exposure. I have always used lip products to the point of addiction. So, last year I got rid of my usual balm Lypsol, which I loved, and wanted to find something that didn’t have yucky ingredients that would heal my lips so I wasn’t always using products. I’m using HPA Lanolin which helps but I still use a lot of it.
        I got cold sores and red, dry skin around my lip area in the fall after a long bike ride in the sun and wind.
        I did see a dermatologist Because it would not heal and she diagnosed it as “ dry lips” lol.
        I used Aquafor and 1% hydrocortisone and it cleared up. Not back to normal, but no more embarrassing redness around my mouth.
        Well, the weather is nice again and a little too much sunshine, I got a few cold sores. They are gone but now I have the dry, red , ugly soreness on my outr lip area again.
        I’m trying to find a product that does not contain hydrocortisone and is healing.
        Is there a product with urea in it for dry, chapped sore lips?

        • Verified Author Samantha Miller replied:

          Hi Ruth
          So glad you enjoyed my article.
          Ruth a number of my clients are using my balm Naturlene on both their lips and around their eyes with great positive results. This formula is soon to be renamed Ceramide as it contains a number of skin identical ingredients that are often missing from the skin as we age, so you are in effect putting back the good stuff.I also think Bio lipid and saviour would be great for you. Samantha

  2. Mehrzad says:

    Thank you so much.
    It would be great if you back up your articles with a couple of references at the end. Nice job, though.

  3. Andrzej S. says:

    Hi,

    If I use a cream with 2% urea (5-6% was irritating to my skin – small red bumps on my higher cheeks and near lipline :(), do I still need to use exfoliating products 1-2 per week? I mean, is using 2% urea cream 2 times a day enough to prevent dead skin buildup that could clog my pores?

    I have a very sensitive skin, which doesn’t like actives like AHA/BHA and physical exfoliation. Even 15% urea peeling (washed off after 5min) once a week was irritating. I suspect that products with acids and physical exfoliation made my skin over-sensitive. I can’t even use 2% niacinamide, which is another holy grail for many people.

    So I’m trying to repair my barrier with the urea cream, gently foam wash and no exfoliating products at all. My skin is getting better, texture is smoother, not so “grainy”, but it becomes quite shiny after 4-6h – I don’t know, if it supposed to be like this or it’s overproduction of sebum or something. It’s not sticky at all.

    Cheers from Poland,
    Andrzej

    • Verified Author Samantha Miller replied:

      Hi thanks for reaching out, at 2% your skin might react i would start at 1% and build up from there. You do not need to subject your skin to peels especially if your skin is already sensitive? Urea is a natural keratolytic, so it gently exfoliates whilst improving hydration and reversing early signs of premature ageing so a great ingredient to include in your skin care range. To rebuild your barrier read this article https://thenakedchemist.com/barrier-repair-the-key-healthy-skin/ and maybe try my H20 skin shot.. Warm regards Samantha

      • Andrzej says:

        Thanks for the answer and for the link 🙂

        “You do not need to subject your skin to peels especially if your skin is already sensitive? Urea is a natural keratolytic, so it gently exfoliates whilst improving hydration”

        Yes, I’m thinking the same 🙂 but is 1-2% really enough to exfoliate? It’s very hard to find any info about this, because it’s usually used in 5% or 10% and many shops that sell raw materials say that it needs to be in >10%.

        I’ve been using 1% for 3 weeks and my skin and texture overall improved, but today I got 2 clogged pores and 2 tiny whiteheads. Does that mean that there is no enough exfoliation?
        I’ll try to increase it to 2%, but I’m still a little confused about urea’s exfoliation power and its minimum concentration.

        I’d be very grateful for any additional advice 🙂

        • Verified Author Samantha Miller replied:

          Hi Andrzej I would look at local suppliers and ask them, it will usually have this information on their data base. It can sensitise some people in higher percentages on the face – where the skin is the thinnest. Because skin conditions arise such as clogged pores can;t be put down to the fact that your skin is not exfoliating there are so many other reasons for these to appear, rememeber your skin natural desquamates it does not require forced exfoliation urea just gives the process a nice little boost whilst hydrating and moisturising the skin…I hope this helps. Samantha

      • Andrzej says:

        Oh and I used it with 0,4% allantoin, it’s very interesting what you wrote, that 0,2% of it has the same keratolytic effect as 10-20% urea. I wonder, if this 1 or 2% of urea in my cream really matters then in terms of exfoliation. I know, these are other substances and the first one promotes healing, I just think out loud 🙂

        • Verified Author Samantha Miller replied:

          Not 0.2% but 1 to 2 percent. Don;t underestimate urea it works even at small percentages i have seen marked improvements in my clients skin, it also depends on the formula it is in – a serum is most effective in my opinion.

  4. Claire says:

    Hi Samantha,

    Thanks so much for your thorough explanations regarding urea. There’s lot of confusion around about the safety of urea in skincare and apparently they mean the preservatives compound and not the hydroxyethyl urea (which I just knew now that they are different after reading your blog-thanks to you!).
    Anyway I have 1 question though. if the company only listed the name “urea” in the ingredients list, does it mean the humectant or the preservatives one?
    Thanks so much Samantha:)

    • Verified Author Samantha Miller replied:

      Hi Claire. I have updated my article as it is confusing for some, but you need to look for pure urea not the preservative, reach out to your supplier they will help you differentiate. kind regards Samantha

  5. Raisa Alferos says:

    Hi! I am so happy I read this blog. I am suffering from fungal acne and I live in the Philippines. I recently learned that Urea is very good in combating the fungi responsible for my acne. There is a product sold here in the Philippines that contains 10% Urea. Is it safe to use on the face as a moisturizer? Here is the link to the product. I hope you can reply. I really am lost. I’ve started using Sulfur Soap and Nizoral shampoo as a mask and its really drying my face. Will Urea Cream help to rehydrate it?

    • Verified Author Samantha Miller replied:

      Hi Raisa so glad you have enjoyed the article I am sorry to hear about your fungal acne, not something I have direct experience with in my clinic, so i would steer you in the direction of a dermatologist in this instance. Every ones skin is different some people tolerate 10% urea others don;t so it is a matter of trial and error as we a re all metabolically different. Just be really really careful what you use on your skin and i never advocate any type of soap as it will really compromise your barrier the pH is just to strong and will upset the delicate micro flora. To hydrate your skin look at using a cream base with humectants or a moisturiser such as fortify that contains skin identical ingredients that are missing. Good luck Samantha

  6. Lauren says:

    Hi. I am looking to incorporate a Korean loation/toner with 3% urea to my routine, but am concerned about its exfoliantion properties. I currently use an 8% aha 4 or 5 nights per week. My day/night moisturiser (the ordinary NMF + Ha) also contains urea, though I’m not sure how much. Do I risk over-doing it? Thank you for your advice!

    • Verified Author Samantha Miller replied:

      Hi Lauren
      I would warn against over exfoliation especially because you are already using an AHA at 8% not advisable long term please be wary, long term your skin can become very compromised and you could do irreversible damage. In fact urea is very mildly exfoliating and should be enough for your skin on its own- so the short answer yes you risk over doing it, please be careful. All the best Samantha

  7. Kalpana says:

    Hi, Samantha–I really appreciated your clarification on the types of urea used in cosmetics. However, if an ingredient just says “urea”, which of the three you mentioned is it most likely to be?

    I have pretty normal skin, not dry, but I also moisturize a lot. When buying body lotions, it seems like a lot of them have urea in them as the fifth or sixth ingredient. How bad is that?? It’s frustrating (and time consuming) to keep finding that out…and also not pay $$$ for something as simple (and frequently used/replaced) as body lotion.

    Thanks for your advice!
    Kalpana

    • Verified Author Samantha Miller replied:

      Hi Kalpana

      Urea when to high a percentage can potentially be an irritant especially on the face. In the future I will experiment with really high strengths and it will be interesting to see what the results are. I do custom blend if it is something you are keen to have done in the future for a body cream. Samantha

  8. Paula says:

    Congrats on the post, very informative! Do you know by any chance if in the UK there are pharmacies where I can produced a 20% urea cream? I used to do that in Brazil and it was so much cheaper than any industrialized product I found here.

  9. Deb says:

    Dear Samatha, I visited with you in December and I am still having problems with my skin esp my nose. You did sens me some of your products but when they arrived, they were all open and solution was everywhere, so unfortunately I was not able to use your products. I did consult with Kristina Holey from San Franciso and did but some of her products! I just recently have had the nerve to use the because my skin is extremely dry! One of her serum barrier restore serum does have urea in it! Is urea safe to use on cracked skin on my nose and I see it has lactic acid in it also. I have been using it everywhere, but on my nose!! What is you opinion on using the serum on my already irritated nose!!! Thank you Deb

    • Verified Author Samantha Miller replied:

      Hi Deb

      So glad you reached out to Kristina though and she was able to advise. Lactic acid is the most mild of ingredients when it comes to acids, but I would think twice before using it on broken skin, I think you are right in using the trial and error approach, your skin will tell you best what it needs, good luck I really hope the products work for you. Warm regards Samantha

  10. Klara Kennedy says:

    Hi Samantha. I have suffered from hand dermatitis and from time to time eczema on my neck and face due to perfumes and skin lotions with irritants. I have only recently woken up one morning to find I have chest wrinkles. I am 51 and going through menopause. My skin is very good and my face wrinkle free. I live in Australia and use QV, dermaveen and recently dermal therapy and have seen good results. will I achieve more success if I tried the Urea creams? Thank you for your time and your blog is fantastic.Klara

    • Verified Author Samantha Miller replied:

      Hi Kiara I do feel the urea creams would be beneficial for your skin. This should really be combined with a very less is best approach to your beauty routine, so avoid the use of actives, fragrances and resurfacing ingredients. good luck Samantha

  11. George Alaja says:

    hi . İ added urea in depilatory cream in 2% -1.5 %
    but after few weeks . I find like crystalıse ın my product .İ thınk it’s UREA .. what is your advices pls ?

  12. Diane says:

    My elderly father was diagnosed with Grover’s disease. It seems the doctors are just shooting in the dark when it comes to trying to find him some relief. He has a rash on his back, neck and sometimes scalp that looks like pimples and intensely itches. I feel bad for him since the itching is very intense at times. Would a lotion with urea help him?

    • Verified Author Samantha Miller replied:

      Hi Diane
      Urea is gently exfoliating, but I’m not sure it will subdue the itching, I would be keen to know what results you have if you do try a formula with urea, for the benefit of my readers. Samantha

  13. Rachel says:

    Hi I have super dehydrated skin due to bha and aha, my moisture barrier is very damaged! My skin itches and I have closed condomes and mild acne! I’ve tried so many things but nothing is working so I’m now trying to be a bit gentle and keep it simple
    I’m using cerave hydrating cleanser, rose water spray, hado labo HA serum, 5% urea facial cream by eucerin, and Vaseline on top at night!
    Is the 5% urea too strong for me? I’ve only been doing this routine for 2 days.
    A few hours into putting my makeup on It literally slides off my face due to the oil…..I just don’t know what to do for the best

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