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It’s getting warmer and that means your shower is probably getting a little cooler—raise your hand if you’ve ever held out on installing the AC in favor of a gratis cold shower. If this is you, you might actually be helping your hair. To shed light on the heated (or cooled) debate surrounding locks and water temp, we reached out to some stylists, a dermatologist, and a trichologist (a scalp specialist) to find out all about the benefits of cold rinsing. For those wondering if they should wash their hair with cold water, get ready to turn the knob because a little cold never hurt nobody.
It Helps Seal the Cuticle
Why should we wash our hair with cold water, you ask? According to Dana Caschetta national trainer for Eufora, “Cold water helps to close the outer layer of the hair.” This closing off helps “lock in color, the benefits of the conditioner, and adds shine and smoothness.”
Eufora’s style director, Mirza Batanovic, agrees: “Cold helps to seal the cuticle, thus sealing in the conditioner.” A closed cuticle takes hair to shine city and, Mirza adds, “reduces tangles.” Of course, you don’t need to go below freezing to see results, water that’s on the cooler side works just as well. Actually, not just cold but all water temperatures have an effect on your mane. “Warm water opens the cuticle and allows your shampoo and conditioner to penetrate the hair. Once the conditioner has been on for its recommended time, you should rinse it out with cooler water to seal the conditioner into the hair,” he advises on getting the best of both worlds. “Cool water helps to seal everything in by closing the cuticle back down.”
It turns out that the temperature of your water may be just as important as the product your using—or may change the way the product reacts to your hair. “Hot water keeps the outer layer open, which may cause the hair to look frizzy and dull,” explains Dana, whereas “cool water seals the outer layer and has a reflective shine to it. Any products used afterward for styling will work a bit better as they have a nice even surface to lay on.” Dana also swears by cold water’s benefit on the scalp. “Cold rinsing can help soothe irritation and prevent dry flakiness,” she adds.
Getting Colder
Liz Phillips, a trichologist at the NY Philip Kingsley Clinic, notes that water temp is largely a personal preference, but when clients come to the clinic they can expect their hair to be washed in warmer temperatures. “Warmer temperature will ensure a gentle but thorough cleansing action of the shampoo to remove oil/sebum and product from the hair,” she says. “This is particularly important if the scalp produces a lot of oil and the hair is fine.”
Rinsing hair with cold water, however, is definitely a good idea if you’ve recently had your hair dyed, conditioned, or treated. Dermatologist Dr. Kally Papantoniou weighs in. “Cold water can help prevent the loss of natural oils from hair and may help conditioning agents and hair masks to work better. It may also allow keratin treatments and hair dye to last longer,” she says. This is because overly hot temperatures may strip hair of oils and wash away too much, if not all, of your product. “When we are looking to clean hair that has a lot of buildup, warmer temps are better. For dry hair, and hair that is being conditioned, a colder rinse will allow the product to adhere to the hair and work its way into the hair cuticle,” she explains.
What’s in the Water?
When hair is damaged, water can actually get inside the hair, causing “hair swell” aka frizz, or the enemy. “Hair swelling occurs when the cuticle around the hair shaft becomes damaged, water can penetrate and lead to the hairs swelling with water. This can cause the hairs to stand out and look frizzy,” says Dr. Papantoniou.
As important as the water temperature is to the appearance of your tresses, pH can have an even greater impact on hair health. PH, which stands for the “potential of hydrogen,” is a scale that measures how acidic or alkaline a substance is—a neutral solution has a pH of 7, with anything under considered acidic and anything over, alkaline. “PH can affect the health of the hair cuticle,” reinforces Dr. Papantoniou. “A high pH will cause the cuticle to open, and a low PH will cause the cuticle to contract. A contracted cuticle is better than open because, with an open cuticle, breakage and swelling become more likely to occur. Scalp pH is naturally low, which creates an environment less desirable to fungi and bacteria.” Everything from water temperature to pH can change the way hair behaves, but for your best tresses, be mindful about keeping it cool.
