The first time you use dry shampoo, it almost feels like magic. Greasy, day-three hair suddenly perks up with life and volume. But, if you go too long without really washing your hair (you know, like, with water), then dry shampoo might start to do more harm than good.
"The name dry shampoo is actually a misnomer because it's not cleaning the hair the way that our traditional shampoos would," Dr. Nada Elbuluk, associate professor of clinical dermatology at USC Keck School of Medicine, tells TODAY.com.
Dry shampoos, which typically come in sprays or powders, are made of starches or alcohols, she explains.
Those ingredients "don't really clean the hair," Dr. Shari Lipner, associate professor of clinical dermatology at the Weill Cornell Medical Center, tells TODAY.com. Instead, they absorb oil, giving the hair a cleaner, fluffier look, Lipner says.
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“Dry shampoo is not a cleansing mechanism for your hair or your scalp,” Dr. Shari Marchbein, clinical assistant professor of dermatology at the NYU Grossman School of Medicine, tells TODAY.com.
“It is a way of absorbing dirt, oil, debris, bacteria and old haircare products that are lying on the scalp and the hair from the preceding days,” she adds.
Is dry shampoo bad for your scalp or hair?
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Dry shampoo is "really not meant to be part of somebody's daily routine," Elbuluk says. "So overuse can certainly affect the scalp and the hair."
When used appropriately, it isn’t likely to cause any major scalp problems for most people. But if you overuse dry shampoo, you might notice irritation of the scalp or folliculitis, which is an irritation of the hair follicles, Elbuluk explains.
Per Mayo Clinic, symptoms of folliculitis, a common condition, include: small bumps or pimples around the hair follicles that can be inflamed, blisters filled with puss that may break open or crust over, skin that itches or burns, and skin that feels painful or tender.
Some people are more likely than others to develop scalp issues after using dry shampoo. That includes people who have sensitive skin, as well as those with certain scalp conditions, like dandruff, seborrheic dermatitis, eczema or psoriasis, Marchbein says.
People who already have conditions like those "should probably steer clear of dry shampoos because they may irritate the scalp more," Lipner advises. Dry shampoo may also interfere with the way topical prescription scalp medications for these issues actually work, Marchbein adds. So people who use those medications should avoid dry shampoo or check with their dermatologist first.
The experts also stress that if you let dry shampoo sit for too long or rely too heavily on dry shampoo without actually washing your hair the traditional way, that could lead to hair breakage.
Is it better to wash your hair or use dry shampoo?
While dry shampoo is a great short-term solution for extending the life of a blowout or getting you from the gym to dinner, it’s not a substitute for actually washing your hair. That’s because the dry shampoo leaves a residue behind on your scalp, and “that residue is something that you ultimately need to wash out,” Elbuluk explains.
Some people may want to use dry shampoo more often because they’ve heard that it’s bad to wash your hair frequently, Marchbein says, but “that isn’t actually scientifically true.” As long as you’re using gentle shampoos, it’s totally fine to wash your hair every day, she says. And, for people who have dandruff or dermatitis on the scalp, daily washing is usually recommended, Lipner adds.
But, Elbuluk says, there are certain times when dry shampoo really does come in handy, like if you’re camping.
Does dry shampoo cause hair loss?
There's no evidence to suggest that dry shampoo directly causes hair loss, the experts say. In fact, in the short-term, dry shampoo can give a volumizing effect that makes your hair look fuller, Lipner says.
But, if dry shampoo is causing scalp issues, that could lead to hair loss down the line, Marchbein says. "Any inflammation on the scalp theoretically could cause hair loss," she explains.
And, because dry shampoo is usually alcohol- or starch-based, it can dry out the hair, Elbuluk explains. "As you dry hair out, that also affects the hair health, and it can become more prone to damage and breakage," she says.
How often should you use dry shampoo?
As convenient as it is, resist the urge to make dry shampoo a regular part of your beauty routine, the experts say. It's best to save dry shampoo for when you really need it and to use it "in moderation" — ideally no more than once or twice a week, depending on what your scalp can handle, Marchbein says.
Elbuluk also suggests her patients use dry shampoo no more than once or twice a week.
Ultimately, whether you're using it too often will depend on your individual skin and hair, Lipner says: "It's really going to depend on the person, how oily their hair gets and if they have dandruff."
For instance, Marchbein says she never uses dry shampoo because her hair is too fine and needs to be washed every day to avoid getting oily.
Dry shampoo alternatives
The best alternative to dry shampoo is washing your hair with shampoo and water, the experts say.
And more than anything, remember that dry shampoo should not be used as a substitute for actually washing your hair regularly, they advise.
"(Dry shampoo) can serve a role and be beneficial," Elbuluk says, "but I definitely wouldn't want someone to start over-relying on it and incorporating it into their everyday routine."
This story first appeared on TODAY.com. More from TODAY: