Last year, Americans spent nearly $17 billion on spa services. A lot of that money went toward facials: treatments that claim to remove blemishes, combat wrinkles, moisturize, regenerate, tighten and otherwise beautify the skin so that your face looks fabulous.

But is there evidence to support the claims (and costs) of these treatments? Experts say it depends on the type of facial, where you have it performed and the skin benefit you’re hoping to get out of it.

“I was at this beautiful spa in Santa Fe, and the esthetician giving me a facial said the next citrus emollient she was going to apply would help cleanse my liver,” recalls Ushma Neill, editor-at-large of the Journal of Clinical Investigation and vice president of scientific education and training at Memorial Sloan Kettering Cancer Center. “I almost sat up in disbelief.”

That experience, Neill says, prompted her to investigate the existing science on spa facials. She published her findings in a 2012 report. Her conclusion? “I realized just how useless it all was,” she says. “I haven’t had a facial since I wrote that article.”

Neill says she doesn’t dispute claims that facials can temporarily revamp the skin by “moisturizing it to the max” and removing pimples and other blemishes. But when it comes to many of the fancier, pricier services that claim to combat aging or inflammation—everything from ozone and antioxidant treatments to stem-cell extract applications—most of that stuff is “complete malarkey,” she says.

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Other experts reiterate that point. “As a dermatologist, I see a lot of patients with misperceptions about different creams and procedures and the whole concept of facials,” says Dr. Joel Cohen, an associate clinical professor of dermatology at the University of Colorado and director of AboutSkin Dermatology and DermSurgery near Denver.

Apart from moisturizing the skin, Cohen says most topical creams are unlikely to provide much lasting benefit—especially if applied sporadically and only in a spa setting. And while some chemical peels that use substances like salicylic or glycolic acid can help stimulate skin cell turnover and repair, Cohen says proper daily skin care—regular cleansing and applying moisturizer and sunscreen—are a lot more likely to be helpful.

It’s also important to differentiate among the many different types of facial treatments.

“If you’re talking about a standard facial”—usually a deep cleaning, followed by some kind of pimple/blemish extraction, a massage and steam treatment, a mask or peel, and a final application of some type of moisturizer—“those are about improving the appearance of skin here and now,” says Dr. Adam Friedman, an associate professor of dermatology and director of translational research at George Washington University. “But when you get into microdermabrasion treatments and microneedling and a lot of the other stuff, you’re getting into the world of anti-aging treatments,” he says. Here, the evidence is mixed or non-existent.

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“My own impression of microdermabrasion treatments is that they’re a total hoax,” Friedman says. “It’s basically a physical exfoliant”—similar to a store-bought scrub that mechanically removes the top layer of dead skin—“that costs a lot of money.”

Microneedling facials, in which short, very thin needles puncture the skin in order to increase collagen, may actually come with some benefits, he says. Studies have shown microneedling—by triggering collagen formation and skin remodeling—is an effective treatment for reducing the visibility of wrinkles and scars. “Because they’re punching all the way through the top layer of the skin, they create these channels of injury that may allow better penetration of topical treatments,” Friedman explains.

Better penetration is crucial, because some of the things science says can benefit your skin—from vitamins C and E to retinoids and collagen-stimulators—break down when exposed to oxygen and UV light. “The skin is an amazing barrier, and so it takes a long time for things to get through it,” Friedman says. The longer your creams are sitting on your skin and exposed, the less likely they are to do any good. (For this reason, he says most topical skin creams are unlikely to do much more than moisturize.)

But while microneedling could allow better penetration of helpful skin vitamins and nutrients, it also opens up your skin to irritants or allergens. “There’s always the potential to do more harm than good,” Friedman says. “Aftercare is as important as the treatment itself.”

For all these reasons, both he and Cohen say that people who really want to address skin issues—from wrinkles to age spots, acne and pigmentation flares—should spend their money at a dermatologist’s office, not at a spa. While spas are mostly about pampering and short-term skin improvements, Cohen says a cosmetic dermatologist will provide an informed medical evaluation and the most effective method of treatment—whether that’s microneedling, a specific retinoid cream or some combination of treatments. A trained dermatologist can also identify skin cancers and other issues that go beyond cosmetic imperfections.

“I have people who come in and say, ‘My sister had a treatment that made her skin look incredible for a few weeks, and I want that,’” Cohen says. “But everyone’s skin is different, so it’s not that simple.”

Another big caveat when it comes to spa facials is the lack of regulation surrounding the industry. Friedman says it’s impossible to make blanket recommendations because there’s no way to know what procedures or protocols an individual spa is following.

Put all this together, and you get a lot of unknowns and ambiguities around facials.

“I think there’s very little benefit you could glean from a facial that you couldn’t get on your own from cleaning the skin twice a day and applying moisturizer,” Neill says. And no, she’s not talking about expensive topical ointments and French under-eye creams. “I use Oil of Olay and St. Ives—that’s about it,” she says.

Friedman says a lot of consumers are lured by niche products featuring exotic ingredients from far-flung places. But he has more faith in big, well-known brands. “They have the resources to evaluate their products in clinical and preclinical settings,” he says.

“I’m also fastidious about wearing sunscreen,” Neill adds. In contrast to the science on facials, there’s a huge body of evidence showing that sun exposure ages skin. One recent study found that UV-light exposure accounts for 80% of visible facial aging.

None of this is to say that facials don’t feel great and won’t improve the appearance of your skin for a few hours—or even a few days or weeks. It’s also possible that research will eventually prove the worth of some popular treatment methods.

But if you want to look your best and maintain the youthful appearance of your skin without spending a fortune, regular washing, moisturizing and applying sun protection are what matter most.

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