Although it might seem counter-intuitive to put oil back into hair to clean it, the science behind it actually makes perfect sense. Oil fights oil, so naturally a cleansing oil is an ideal product to remove excess scalp oil, sweat and dirt. Plus, it's incredibly hydrating. After all, there's a reason we use oil on our bodies to soothe dry skin. Why shouldn't our hair receive the same benefits?
"Cleansing oil treatments act as a way of ridding your scalp of any unwanted impurities or built up sebum in the hair follicle," explains Marcos Trueba, hair stylist at Sally Hershberger salon in Los Angeles. He explains using a cleansing oil treatment is different than other common hair treatments because instead of putting ingredients back into the hair to repair breakage or damage, a cleansing oil targets the root of the hair to remove oil and grime.
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"When our hair follicle is clogged or has bacteria, we get dry scalp or dandruff, and many times oily hair," he says. "A cleansing oil treatment can help cure dandruff and even balance the amount of sebum your scalp produces." In fact, using a cleansing oil like Shu Uemura Art of Hair Cleansing Oil Shampoo ($57, Birchbox.com), works with your scalp's natural oils to keep excess oil at bay, thus potentially saving you a daily wash.
So how often should you reach for the oil? Really, whenever you see fit. If you notice you're more oily than normal, Trueba says it's time to extract the impurities in your scalp, i.e., shampoo with a cleansing oil. However, if your scalp is really dry and itchy, it's also a good time to apply the treatment to cleanse your scalp and add hydration back in. Try a treatment like Kérastase Elixir Ultime Shampoo ($42, Kerastase-usa.com), which provides rich nourishment and shine all while removing excess oil. It's a great option for those looking for a salon-quality look at home.
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When applying a cleansing oil, Trueba says it's best to focus on the scalp. Massage the oil into the scalp post shampooing, as the initial shampoo rids the hair of any product buildup, thus leaving the scalp a clean slate for the oil to begin to work, he explains. After massaging the oil into the scalp, let it sit for five or so minutes, then rinse it out completely and follow as normal with a conditioner.