An hour’s flight from Tokyo, on the island of Shikoku, is a small, secluded resort called the Utoco Deep Sea Therapy Center & Hotel. It’s the brainchild of Shu Uemura, a man already known globally for his eponymous makeup range. Fascinated by the healing properties of the area’s waters, Uemura decided to harness them into products and build this ultramodern 17-room spa, which opened a year and a half ago. Inside, the spare furnishings suit the remote location. Although you wouldn’t call the decor clinical, this place is certainly not for those who prefer suede walls and chocolates on the pillow. But escaping to an island off the coast makes for a total retreat, and the overall effect is a variation on the way Europeans used thalassotherapy to revitalize and detox two centuries ago.
Unlike the much shallower waters along, say, the coast of France, the seabeds off Kochi’s Cape Muroto are so deep that they are completely static. While the world’s seas move relentlessly, the stagnant depths here have kept all the valuable trace elements of magnesium, potassium, calcium, sulfate, and sodium. Utoco pipes in this concentrated form from about 1,200 feet down and refines it for use in treatments and therapy. From the products to the swimming pool, everything is infused with the vitamin-rich, restorative brew: Guests bathe in it, are massaged in marine mud or detoxifying seaweed, inhale sea fog in the hammam, or simply drink the elements in the water. Meals, which include miso soup with aosa seaweed, grilled fish marinated in rice vinegar, crispy tempura shrimp, and smoked tofu dipped in Muroto sea salt, are cooked with the water as well. According to Uemura, this can improve digestion and skin tone. A Japanese pharmacological study also focused on the water’s capacity to lower cholesterol. Whatever the case, taking the waters at Utoco offers new meaning to "seaside resort." $560 per person, with breakfast and dinner; 81-08/8722-1811; utocods.co.jp