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Indian Springs Resort and Spa in Calistoga, California.
Photo: John S. Lander/Getty Images

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The Truth About Mud Baths

People have been bathing in volcanic ash to purify and heal themselves for generations — but is all that mud doing anything?

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The air lingered like a dense fog. Pools of water collected on the floor, and exposed pipes hung overhead. The room’s single door was battered and worn down. It was the perfect environment for diving into my first volcanic-ash mud bath — a centuries-old ritual that is said to improve joint and muscle pain and remove excess dirt from the skin. Or at least that’s what Calistoga’s Indian Springs Resort in Napa Valley would like you to believe.

On a daily basis we’re sold on the healing properties of face cream to reduce wrinkles, lotion to eliminate stretch marks, shampoo to increase hair growth — you name it. Most of us have accepted these products as mere marketing gimmicks to get us to buy more, and we do, gladly, even if those claims don’t end up panning out.

But if those supposed “miracles” are nothing more than modern marketing techniques, what of the ancient healing powers of volcanic ash like that found in Calistoga? Is there any credence to those claims?

It seems harder to conclude that these mud baths are nothing more than marketing. People have been bathing in weathered ash from the world’s active volcanoes for centuries.

Calistoga, the very place where I was bathing, was put on the map when word spread that its hot mineral springs had “healing properties;” the region’s original inhabitants, the Wappo Indians, discussed the water’s powerful qualities beginning as early as 2,000 BC. Resorts in Costa Rica, St. Lucia, and Colombia have operated on those same time-honored claims, luring tourists to their geysers and mud baths in part because of these wonderful healing effects.

To this day, we believe in the influence of the earth’s natural properties. Like charcoal and coconut water, mud baths have some mysterious power — they’re a kind of natural, restorative cure-all pulled straight from the earth. But are claims about the healing effects of mud baths (literally) just the oldest marketing trick in the book?

I was there to find out.

At the Indian Springs mud baths.
Photo: Indian Springs Calistoga

According to the Indian Springs website, “Indian Springs mud and mineral baths are known for their special qualities. The vein of volcanic ash found on our property is the source of the 100 percent pure ash we use in our mud baths, a rarity among spas.”

After showering, a female mud-bath attendant showed me how to dip into the vat of mud in the large concrete tub: Sitting on its edge, I flung myself in feet first. I thought I would sink, but instead I lay flat, suspended above the mud, totally exposed. Seconds later, the attendant began wrapping the thick, chunky mud around me with swift precision. It felt very “back to nature,” in a poetic sort of way.

With the steam rising, the cement-like mud surrounding every inch of my body, and a troubling inability to check Facebook for 15 minutes, I began to feel something akin to peace.

As the mud began to seep up toward my nether regions, I remembered what the spa director, Yalda Teranchi, told me just before I jumped in: “The mud bath, because of its volcanic ash, has healing properties that are detoxifying, so it pulls impurities out.” Teranchi says the combination of volcanic ash and Calistoga’s natural geyser water can improve circulation, restore sore muscles, and even treat skin reactions like eczema. Was this what was happening to me? This combination of mud, heavy and overwhelming, that slightly restricted my ability to breathe, and the peaceful silence surrounding me immediately set me into a meditative state. I felt cramped, but complete; the warm mud wrapped around every inch of my body was debilitating, yet purifying. And once I washed the thick mud off my naked body (the next step in the process), my skin felt electrified, like it had transformed instantaneously.

According to volcanologist David Damby, expert member of the International Volcanic Health Hazard Network (IVHHN), my skin probably wasn’t transforming in an instant — not by a long shot. “There is no scientific evidence to prove volcanic ash, in itself, can cure skin rashes, aches, or pains,” he told me. “Any experienced benefit is likely due to water chemistry and temperature rather than the ash itself.”

That part checks out — relaxing in a stress-free environment for 15 minutes will do wonders for anyone, and combined with geothermal water (earth’s soft water , which is naturally rich in nutrients), your skin can’t help but loosen up. Plus, when the ash is combined with water, it can work as a natural exfoliant, much like over-the-counter clay masks.

Another angle on the Indian Springs Resort and Spa in Calistoga, California, where the author tried the mud bath.
Photo: John S. Lander/Getty Images

I then discovered a mud-bath therapy study from Silene Springs at Italy’s Chianciano Spa. Scientists, hoping to understand the efficacy of those antiquated mud baths’ “healing properties,” devised a test around a group of patients suffering from osteoarthritis. After a year of observation, during which half of the patients enjoyed a handful of mud bath treatments, the scientists emerged stunned — the results proved that mud-bath treatment actually works. The group that enjoyed a dip in Italy’s famed mineral water mud baths were in luck: The treatment “remarkably improved the clinical conditions of patients with knee arthritis and significantly reduced the frequency and severity of symptoms.” So maybe those Wappo Indians were onto something.

And it can’t be denied that after the hour-long treatment at Indian Springs, I was the definition of relaxed, soothed, and refreshed — and my body certainly felt better. I could understand where the faith in this ancient ritual had stemmed from.

Damby doesn’t deny this aspect of the baths. “I’m cautious of saying ‘healing,’ as medical evidence is fairly neutral,” he says. “But the benefits of relaxation are widely accepted, and mud baths are a time-honored tradition. There is some evidence that the baths can help in pain management, [but] not healing.”

The difference may have less to do with properties of the earth purifying our bodies from the outside and more with unwinding from the inside. I could see that: By the end of a post-mud sauna session gently enhanced with therapeutic music, I was drinking their cucumber water Kool-Aid. Whether or not my body had physically experienced anything as a result of the bath didn’t matter; I truly felt rejuvenated.

And though they might not have miracle curative effects, the good news is that the baths aren’t harmful, either. While we know volcanic eruptions are bad for the environment, as gas and ash emitted during these unpredictable natural disasters can affect crops and drinking water, the ash in your mud bath is different.

“It might still be called ash because it’s the parent material, but it’s not the same stuff [that’s harmful to humans right after eruptions],” Damby confirms. On top of that, “by wetting the ash, you’re eliminating any potential exposure.”

So even when a resort offering volcanic ash mud baths is located dangerously close to an active volcano, like the one that erupted a mere seven years ago at Tabacon Grand Spa Thermal Resort in Costa Rica, ash collected for spa treatments is safe.

My hour in the treatment rooms, complete with a cool down that included a cucumber-infused washcloth wrapped around my face, was near perfection in terms of spa experiences. And gosh darn it if I didn’t feel a noticeable difference in the way my skin bounced, even days later.

I hate to admit that it’s all a hoax, despite the evidence proving otherwise, mostly because we all need a little healing every once in a while — internally, just as much as externally.


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