Every season there are new fads in the spa world (think: oxygen facials and bull testicle hair masks), and 2013 is no exception. See which treatments are hot right now thanks to this fascinating research done by Allure.

Those sour-milk baths Cleopatra took a few thousand years ago might be the first official spa treatment in the history books. Since then, we've gotten a little more savvy — sweat-inducing hammams, hallucination-inducing detox clinics, collagen-stimulation chambers, not to mention the endless varieties of massage. So what's new in the spa world this year?

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1. The trend: The lost art of bathing.
These aren't the clammy stone caverns full of hirsute men you might imagine. The new Russian- and Roman-inspired baths are more luxurious and sexier than their predecessors. From vast electricity-free villas to bathing coaches that hand-pour your soaks — olive oil, red wine, or cava upon request — this is hedonism at its finest.
Where to do it: Aire Ancient Baths, a 16,000-foot underground brick-and-glass den in New York City's TriBeCa. One Allure editor called it a "temple of indolence." The hottest dipping pools are 107 degrees; the cold plunges are icy at 50 degrees. Gauzy curtains, heated marble floors (for laying, not walking), terra-cotta lanterns and a no-talking policy turn a pretty basic pursuit — floating in water — into a ridiculous pleasure. Aire admits only 25 bathers every two hours, so please, don't tell your friends.
Aire Ancient Baths, 88 Franklin St., New York, 212-274-3777


2. The trend: Telomere analysis.
Menus that are larded with pseudo-scientific terms are a personal pet peeve, but the spas that offer this cutting-edge treatment might actually be onto something. It's a crazy-customized approach to long-term health, weight loss, and overcoming fatigue. Upon arrival at a clinic, guests have their blood drawn or inner cheeks swabbed for a little chromosomal analysis to predict the longevity of cells. A personalized program of acupuncture, lymphatic drainage, hydrocolon therapy, aromatherapy, etc. is then prescribed. One size does not fit all.
Where to do it: The Sha Wellness Clinic, on the outskirts of Villa de Altea in Spain, is worth busting out your passport for. The sleek hilltop compound even looks macrobiotic, and no two stays are alike. A two-week stay is "strongly recommended."
Sha Wellness Clinic, Verderol 5 El Albir 03581, Alicante, Spain, 34-966-811-199

3. The trend: Healthy hotels.
Historically, and at least according to R Kelly's "Ignition Remix", hotels are hotbeds of excess: room service, oversleeping, and other, uh, indoor sports. But the golden age is over, and "wellness suites" are popping up in hotels the country over. In-room spinning bikes and Physique 57 DVDs aren't rare amenities; UV-light-emitting bathroom mirrors trigger feel-good brain chemicals like serotonin and dopamine. Your next room-service binge could be gluten-free and vegan.
Where to find it: Believe it or not, the city of sin. Mornings at the MGM Grand in Las Vegas start with a vitamin C-infused shower to neutralize chlorine levels in the skin, and at night, floor-mounted LED lights illuminate pathways without disturbing melatonin production. (I have to wonder who's worried about melatonin production in Vegas.)
MGM Grand, 3799 S Las Vegas Blvd., Las Vegas 702-891-1111

4. The trend: 24/7 relaxation coaching.
We've outsourced blowouts and braids, so why not relaxation? Specially trained wellness coaches pick calming massages and facials specifically calibrated to your skin type and stress level. Your coach will also appear at choice moments to hand you a smoothie or chilled towel.
Where to get it: A stay at the LIME Spa at Per AQUUM in the Maldives (pictured above) opens with a lengthy consultation. Facials are custom-tailored, and treatments can be administered in a private outdoor sanctuary or a cabana with a transparent floor overlooking the water. Don't worry about getting lost among the 47 private villas — your fairy godmother, er, wellness coach is never far from sight.
LIME Spa at Per AQUUM, Forum #16-01, 583 Orchard Road, Singapore 238884, 65-595-0300

5. The trend: "Earthing."
This one sounds a little Portlandia, even to me. Earthing refers to making direct contact with the earth's surface. The claim: Grounding the body to the earth's electron-rich elements stabilizes our natural electric rhythms, reducing inflammation and lowering blood pressure. All of this is accomplished — deep breath, because this'll blow your mind — by walking barefoot outside.
Where to do it: The Bathhouse Spa at Calistoga Ranch in Napa Valley. Hikers traverse "sandy soil with loose rocks" on the 157-acre complex, and Steve the gardener teaches vineyard management. Even the nightcaps there are healthy: You can get a wine facial with Steve's own Sotero's Cabernet Sauvignon. It all comes full circle.
The Bathhouse Spa at Calistoga Ranch, 580 Lommel Rd., Calistoga, California, 707-254-2800

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