Urea: An Unsung Hero
As a word, urea suffers from some unsexy associations (urine and Uranus come to mind). As an ingredient, it doesn’t get nearly as much attention as hyaluronic acid or peptides. We at Skindie noticed a pattern — some of our favorite products like Clinique’s Dramatically Different Moisturizing Lotion+ featured an unsung hero in skincare formulation, urea. But as both a humectant and a chemical exfoliator, urea is a powerhouse ingredient that has been used in traditional skincare as well as clinical dermatology for decades — read on to find out why.
Urea’s origin story
Urea (or carbamide) has a lot of street cred — it has been used as a healing ingredient and topical treatment for infections since Dutch scientist Herman Boerhaav first discovered it in the late eighteenth century (although French chemist Hilaire-Marin Rouelle is often credited with the discovery). Urea is also the first organic compound to be developed in a lab from inorganic compounds (silver cyanate and ammonium chloride) by German scientist Friedrich Wohler in 1828. Interestingly, this development put to rest the concept of vitalism, the idea that only living organisms can produce organic compounds.
In the last 50 years or so following the discovery that urea is critical to moisture regulation in the skin, this ingredient has become more common in cosmetic, dermatological, and pharmaceutical formulas as a topical agent to treat dry skin disorders. If you want to geek out more on its history, check out this podcast episode from Chemistry World.
The science & what does it have to do with urine?
Urea is an organic compound that is a by-product of metabolic functions, and is found in, yup you guessed it, urine (as well as sweat). It is a skin-identical ingredient, which means that it is naturally occurring in the skin (and continues to be a synthetic ingredient, like hyaluronic acid). It is one of several natural moisturizing factors (NMFs) in the skin which include amino acids, pyrrolidone carboxylic acid (PCA), and lactate. NMFs are humectants that bind water into the skin and also help protect the skin barrier/lipid barrier.
Urea is chiefly a humectant that helps hydrate skin (ICYMI, here’s the difference between hydration and moisturization), but has a host of other benefits and clinical applications. Urea is also a keratolytic agent that helps break down outer layers of the skin (bound together by keratin) to allow for deeper hydration as well as penetration of other ingredients. It’s also an antifungal. This triad of properties makes urea especially effective at alleviating conditions like excessively dry skin, atopic dermatitis/eczema, contact dermatitis, calluses, psoriasis/seborrheic dermatitis, athlete’s foot, keratosis pilaris (KP), pruritus (itchy skin), and certain nail disorders.
Types of urea are sometimes referred to by the concentration at which it is included in a formula. Typically, higher concentrations can help to remove thick, tough layers of dry skin. Higher concentrations, like Urea 40 (i.e., urea at a concentration of 40%), can be found in products targeting dry, cracked hands and feet. Types with lower concentrations, including Urea 20, Urea 10, and even tinier concentrations, can be found in gentler formulas whose chief function is hydration.
Go get ‘em
What are some products we’re loving that contain this hero ingredient? For starters, make sure to check out exactly what the ingredient label says because urea shouldn’t be confused with diazolidinyl urea, which is a preservative that releases formaldehyde and doesn’t perform the same functions as urea. For face, we recommend the Matter of Fact Ascorbic Acid 20 Brightening C Serum and Clinique’s Dramatically Different Moisturizing Lotion+. For body and specific conditions, try Eucerin’s Roughness Relief line, Cerave’s Psoriasis Moisturizing Cream (5% urea), Cetaphil’s Daily Smoothing Moisturizer for Rough and Bumpy Skin (20% urea), and Goldbond’s Ultimate for Feet Healing Foot Cream with Aloe.
Urea is a versatile ingredient with demonstrated efficacy and minimal controversy (a combination that is hard to come by in the beauty world these days). Whether or not urea gets its 15 minutes of marketing fame, we here at Skindie believe that you’ll see it pop up on ingredient lists more frequently. And when it does, you’ll be waaay ahead of the game.