It can also help with dullness caused by buildup. “Vinegar also helps break down product and mineral buildup, which is often why hair looks dull in the first place,” says Lee. “It’s a gentle reset more than a miracle.” It’s not a substitute for a good shampoo, though. “Acidity alone does not guarantee effective buildup removal,” says Joe Cho, Team Lead of Media Relations at Medicube.
Who Should Try It?
Lee says Korean hair vinegar works especially well for “people with hard water, since mineral buildup makes hair look flat and feel rough,” along with anyone who uses a lot of dry shampoo or styling products. Color-treated hair can benefit, too, since a smoother cuticle makes color look shinier. Byun also recommends it for finer textures. “It works well for fine hair that falls flat easily and scalps that get oily quickly,” she says.
The Benefits
The most obvious benefit is shine, and you’ll usually see it after one wash. “A mildly acidic wash or treatment helps the cuticle lie flatter, so hair looks shinier and feels smoother,” says Lee. If you color your hair, there’s another bonus. “It’s also wonderful for color-treated hair, because a smoother cuticle makes color look more vibrant,” says Byun. For oily scalps, it can even leave things feeling fresher between washes.
The Downsides
Acid isn’t gentle on every scalp. “If your scalp is very dry or sensitive, skip it or use a very mild formula,” says Byun. “Skip it if you have eczema, psoriasis, or any broken skin. If you have dandruff or seborrheic dermatitis, start with a medicated shampoo.” Ingredients matter, too. “Even a formulated hair vinegar can irritate some people, depending on its acidity, fragrance and other ingredients,” says Lim. And if your hair is badly damaged, keep your expectations in check. “While acidic products may temporarily improve smoothness, they cannot reverse structural damage,” says Cho.
How to Use Korean Hair Vinegar
Order matters here. Use it after shampoo and before conditioner, and there’s a reason for that timing. “Right after shampooing, your hair and scalp are at their highest pH, so that’s when an acidic rinse works best,” says Byun. Work it through damp hair and onto the scalp if the product says it’s safe there, then follow her method: “Leave it on for one to three minutes, rinse with lukewarm or cool water, then apply a light conditioner, mainly on the ends.” Some formulas are leave-in, so always check the label first. If you’d rather make your own, Byun’s ratio is a good place to start. “Dilute one to two tablespoons of apple cider vinegar in about two cups of water and start mild,” she says.
Less is more when it comes to how often you should use this type of product. “Start with once or twice a week. If your scalp is oily or your water is hard, you can use it a bit more. If your hair is dry or fine, use it less,” says Dr. Byun. Your hair will let you know when you’ve overdone it. “If your hair starts to feel squeaky or straw-like, that’s the signal to scale back,” says Lee. “I’ve found that less often usually gives better results than more.”
Is It Safe for Color-Treated Hair?
“For color-treated hair, choose a rinse specifically labeled color-safe. ‘Hair vinegar’ alone doesn’t guarantee compatibility,” says Lim. After a fresh color appointment or a keratin treatment, give it some time. “Just wait a few days after coloring or a keratin treatment, and check with your stylist,” says Dr. Byun. If you wear extensions, Lee recommends caution: “With extensions, keep the products away from tapes, bonds, and glued areas, since some can loosen with certain ingredients.”
