As a means of providing long-term relief from chronic pain, flotation tanks simply don’t hold water, according to a study published in JAMA Network Open. To test the true potential of flotation restricted environmental stimulation therapy (REST)—which involves floating inside a soundproof, lightless tank filled with salt water heated to skin temperature—investigators focused on 99 adults who had been struggling with pain for at least 6 months between 2018 and 2020. One-third of the patients were randomly assigned to undergo flotation tank therapy. Another one-third was assigned to a placebo tank environment—the same floating tank but with diminished water buoyancy and far less sound and light control. A control group was told to continue their baseline pain therapy. The flotation tank groups underwent five sessions, lasting 60-90 minutes each for nearly 3 weeks. Pain relief was assessed 1 week, 3 months, and 6 months after the last session. Both the REST group and the placebo tank group reported significant short-term drops in pain intensity and anxiety, and a reduction in the areas of their body affected by pain. But REST appeared to provide no appreciable leg up when it came to long-term chronic pain relief. “We found no long-term effects of floating on chronic pain, but strong short-term improvements,” a coauthor said. “These improvements were similar in the placebo group, suggesting that they might not be caused by sensory deprivation or effortless floating as previously thought.”