If you’re someone with dry hair and a perpetually itchy scalp, you’ve likely tried more than your fair share of haircare products in an attempt to alleviate your symptoms. While charcoal, salicylic acid, tea tree oil, peppermint oil, and apple cider vinegar are thought to be the be-all, end-all ingredients for scalp care, according to experts (dermatologists, cosmetic chemists, and scientists alike), urea can prove beneficial, too.
What is Urea?
Urea, also known as carbamide, is a moisturizing compound that’s naturally produced on your skin when the body breaks down proteins. “It’s found in urine and other bodily fluids, including sweat, blood, and human breast milk,” says board-certified dermatologist Steven Shapiro, MD. Urea is also made synthetically in a lab for use in cosmetic and beauty products.
Urea is a great hydrator as it draws moisture deep into the skin or hair. (Fun fact: Urea is also used in professional tie-dye applications, as the organic compound helps draw dye deeper into the fabric.) On the flip side, it can be irritating if it comes into contact with your eyes or mouth. We spoke with the experts to break down the best way to use urea on your hair.
Meet the Expert
"Urea is an excellent moisturizer and humectant that is widely used in skin and haircare applications,” explains Clean Cosmetic chemist Krupa Koestline.
Thinking about giving it a try? Ahead, learn everything there is to know about urea in haircare.
Urea for Hair
- Type of ingredient: Hydrator
- Main benefits: Hydrates skin, gently exfoliates, reduces inflammation
- Who should use it: In general, anyone with a dry, itchy scalp can benefit from incorporating urea-infused products into their routine.
- How often can you use it: Koestline recommends starting by using a urea-infused tonic or shampoo just one to two times a week. If the products you opt for have low concentrations, Shapiro says that daily use is fine. "You will also want to keep it away from your eyes, nose and mouth because it can cause irritation," says certified trichologist Gretchen Friese.
- Works well with: According to a study, urea works especially well with lactate, polidocanol, and licochalcone A. “Together, they hydrate the scalp, balance the oil secretion, reduce inflammation, and help reduce itchiness,” Koestline says.
- Don’t use with: According to the experts we spoke with, there aren’t any major combination concerns when it comes to urea in haircare.
Benefits of Urea for Hair
Even though urea is found naturally in our bodies, synthetic urea (which is made in a lab) is added to many personal care products and has many benefits for the hair and scalp. Although there are currently no studies on the effect of urea just on the hair strands, research has shown it is quite beneficial to the skin and scalp—and a healthy scalp means healthy and shiny hair. Here are all the benefits of urea for hair:
- Alleviates an itchy, dry scalp: A dry scalp is often an itchy scalp. Urea is considered a humectant for its ability to moisturize the skin on the body and scalp, which helps provide relief. Studies have shown that tonics applied to the scalp that contained urea reduced inflammation and itchiness.
- Decreases dandruff: Shapiro says that urea is most beneficial for those with dandruff. “It has antifungal effects, meaning it prevents the growth of bacteria, molds, and yeast,” he explains, noting how it helps curb dandruff.
- Potentially stimulates hair growth: “Because urea helps with moisture retention, it can improve the quality of the skin on your scalp, thereby supporting healthy hair growth.” Shapiro explains.
- Promotes a healthier scalp: Urea increases the water content of the top layers of the scalp or skin, which means it helps promote a healthy, hydrated scalp. In addition, it helps balance oil secretion and decrease inflammation which all contribute to healthy hair.
- Exfoliates the scalp to eliminate flakes: For those with flaky scalps and/or dandruff, urea is considered a keratolytic agent—meaning it removes flaky and scaling skin, as well as gets rid of dead skin buildup.
Hair Type Considerations
While folks with dry, itchy scalps or dandruff benefit the most from urea-infused haircare products, everyone can enjoy occasional use. After all, since urea lightly exfoliates the scalp, reduces inflammation, moisturizes hair, and promotes a healthier scalp overall, it makes for the ultimate treatment. "Dry/coarse and curly hair are great textures for urea because it can help moisturize and prevent breakage," says Friese.
The only people who should fully steer clear of the ingredient, according to Shapiro, are those who are allergic to it. In general, keep the product only on your hair and scalp and watch for signs of irritation or an allergic reaction. "You will want to keep it away from your eyes, nose and mouth because it can cause irritation," explains Friese.
While urea is widely used in skincare and haircare products, it’s a disputable ingredient thanks to its uses in harsher formulations, like fertilizer. “There are three forms of urea: hydroxyethyl, diazolidinyl and imidazolidinyl,” Shapiro explains. “All are somewhat controversial because they release formaldehyde, an organic compound that can have carcinogenic effects at certain quantities.”
As a result, urea can potentially cause cancer (though there aren’t a ton of recent studies documenting such). You can minimize your risk by keeping an eye out for the right kinds of urea in your haircare products. According to Skin Deep site, the Environmental Working Group's database of beauty ingredients, hydroxyethyl urea is the safest version of the compound, ranked at 1 (green) on the SkinDeep scale, while diazolidinyl and imidazolidinyl urea are both ranked at five (yellow). It's worth mentioning that, because of this, Sephora has mentioned both yellow ingredients among their list of no-go ingredients for their Clean at Sephora program.
How to Use Urea for Hair
Even with potentially harsh side effects, urea remains a common ingredient in haircare products thanks to its many benefits. "Using a shampoo, conditioner or leave in treatment [with urea] are all good ways to use it," says Friese. You want to ensure you're reaching for the right type of urea (hydroxyethyl urea) when you're considering adding it to your shower lineup—especially if you have sensitive skin and want to avoid the risk of irritation, says Koestline.
When looking to add urea to your haircare regimen, Shapiro and Koestline recommend steering clear of DIY treatments, as it takes careful formulations to deliver the benefits of urea with as few potential side effects as possible. “The concentration of urea in a formula is extremely important and it should not be used in a DIY product,” Koestline explains. “If the concentration is too high, it can exfoliate too much and cause more damage than good.”
With that in mind, Koestline says that it’s best used in store-bought leave-in scalp products or shampoos. Here are several ways to use urea for your hair:
Dandruff shampoos: Shapiro says that urea-infused shampoos are a great line of defense against dandruff, as urea can help fight the fungus that causes flakes in the first place. Follow the directions on your specific hair product, but, in general, massage the shampoo into the scalp and work it through the ends of your hair. Rinse well and follow up with a conditioner.
Scalp treatments: Urea-infused scalp serums are ideal for those who are experiencing an irritated and itchy scalp and want a more concentrated treatment These type of serums or lotions are applied directly on the scalp and left in so the ingredients can work their magic.
Leave-in Conditioners: Leave-in conditioners with urea provide several benefits as they moisturize your hair, protecting it from heat styling and promoting a healthy scalp.
Styling products: “You can also use styling products with urea to hydrate your hair,” Shapiro adds. “In fact, it’s a common ingredient in products for curly hair because curly hair is more prone to dryness, breaking, and splitting.”
In-salon Brazilian Blowout: If you prefer in-salon treatments, there’s a urea-based option for that, too with a professional keratin treatment. “This popular treatment, which is sometimes called a Brazilian blowout or Brazilian keratin treatment, is a chemical procedure that can make hair look straighter for up to six months,” Shapiro explains. “It’s also used to reduce frizziness and give hair a smoother, shinier quality. Urea, a natural preservative, is a common ingredient in these treatments because it prevents the breakdown of organic compounds.” As a word of warning, in-salon chemical straightening keratin treatments contain formaldehyde, which is a carcinogen.
The Best Products With Urea
Ready to give urea a try? Try some of the below products for a healthy scalp and shiny hair. Look for products that best suit your hair type, such as curly, fine hair, or color treated. "If you have fine hair it may weigh it down a bit if you use too much because it is so moisturizing," says Friese.
This nourishing shampoo is formulated to hydrate and strengthen the hair while cleansing it without stripping strands or the scalp.
Designed to deeply hydrate curls while offering optimum slip and manageability, this rich detangler is a dream for folks with waves and coils alike.
Dry, damaged strands are no match for this coconut-oil- and urea-infused shampoo.
Give your scalp the nourishing deep clean it deserves with this urea-infused serum that soaks into the hair follicles to gently slough away buildup and soothe inflammation on the spot.
This urea-infused shampoo is great for those with dandruff as it helps calm your dry and irritated scalp. Simply massage into scalp and hair and rinse out.
In-salon keratin treatments often use urea. Is this treatment safe?
Keratin treatments are a chemical procedure that result in straight, smooth hair for up to six months. Urea is used in this process as a natural preservative, however some forms of urea have been shown to release formaldehyde, which is a known carcinogen. It is best to stick to more temporary straightening serums and styling products that have less chemicals.
In addition to urea, what other products help treat and prevent dandruff?
Do products that contain urea actually have urine in them?
Don't worry, you aren't putting urine in your hair. Even though our bodies naturally make urea that is found in our urine, cosmetics products and hair products that contain urea do not have urine in them. The urea is made synthetically in a lab.
Urea. Cosmetics Info.
Schweiger D, Baufeld C, Drescher P, et al. Efficacy of a new tonic containing urea, lactate, polidocanol, and glycyrrhiza inflata root extract in the treatment of a dry, itchy, and subclinically inflamed scalp. Skin Pharmacol Physiol. 2013;26(2):108-118.
Celleno L. Topical urea in skincare: A review. Dermatol Ther. 2018;31(6):e12690.
Ewg skin deep® | what is hydroxyethyl urea. EWG.