A practice that holds water
Soothing the body and mind with flotation therapy may help your mental health
Flotation therapy — which involves floating in a tank of warm, salt-saturated water — is a popular form of relaxation. Now, a small but growing body of research suggests it may also reduce symptoms of mental health conditions.
Most float tank sessions last about an hour. During a typical experience, you disrobe in a private room and enter the pod, which may resemble an oversized hot tub. The pod is filled with shallow body-temperature water that's saturated with Epsom salts to buoy your body. You can leave the pod open or close the lid to be cocooned in an environment devoid of light and sound.
Experts say float therapy seems to work on several levels, heightening the senses, aiding relaxation and soothing the body and mind.
“It calms the mind, sharpens our sense of the body and helps us live in the moment — all of which can break the cycle of negative thoughts,” said Sahib Khalsa, principal investigator and clinical director at the Laureate Institute for Brain Research in Tulsa, a hub of float therapy research.
Abby Michel, 27, had been in therapy for anxiety since she graduated from high school. When she moved to Boston in 2019, she became a receptionist at the Indoor Oasis, a wellness centre with float tanks in Newton, Mass. Michel said she began floating regularly, and it became “an important tool in the tool box” to manage her anxiety.
“It's become like a ritual,” she said. “You unwind, and you begin to see life differently, from a more distanced perspective.”
The research on the mental health benefits of flotation therapy is mixed and limited. Some studies have shown that float therapy may reduce symptoms of a variety of conditions, including generalized anxiety disorder, as well as depression and anxiety. The therapy also appears to lower blood pressure and decrease soreness after high-intensity exercise. Preliminary research suggests it may minimize cravings in addiction-related illness.
A 2021 review of the research on float therapy for mental health conditions found “limited evidence” from two randomized controlled trials that floating may reduce anxiety and symptoms associated with anxiety, including muscle tension, sleep difficulties and depression.
Marc Wittmann, a brain and time perception researcher based in Freiberg, Germany, compares the experience to meditation. “During meditation, you feel that you lose your body boundaries and you are more one with the environment,” said Wittmann, who uses float tanks for some of his research.
Wittmann says this dissolving sense of one's body is correlated with lower anxiety, according to his own research that hasn't been published yet.
One explanation for the potential mental health benefits of floating is that it can enhance a biological process known as “interoception.” Interoception is defined as the process by which the nervous system “senses, interprets and integrates” signals from the body — essentially how the brain understands the body. Dysfunction of interoception may play a role in anxiety and eating disorders, among other mental health conditions.
One problem in evaluating specific therapies, such as floating, is defining the mechanisms at work, said Wen Chen, the National Institutes of Health branch chief for basic and mechanistic research in complementary and integrative health. “Is there something special about flotation, or not?” she said. “Maybe you're just in a very relaxing environment, so how unique is it compared to other relaxation techniques we have?”
Some researchers are studying whether flotation therapy can help people with eating disorders. One NIH-funded study, which is recruiting patients, will investigate how augmenting float therapy with interoception-focused psychotherapy can improve anxiety and body image in patients with anorexia nervosa.
In another study, a randomized controlled trial that included 68 women and girls hospitalized for anorexia, researchers reported that twice-weekly float sessions improved patients' levels of body dissatisfaction, a hallmark of the disease.
“Floating might shift attention away from how the body looks to how it feels, promoting a healthier body image,” said Khalsa, the study's senior author.
Consumer demand for float tanks is growing. According to one estimate, there are now close to 400 float centres in the United States, up from about 50 in 2010, with costs ranging from approximately $50 to $100 per 60- or 90-minute session. Many newer float centres are a far cry from the “sensory deprivation” tanks made infamous in pop culture with films like Altered States. Now, people can add calming music and serene lighting to their float experiences and choose less claustrophobia-inducing pools that are more like open-style hot tubs.
Justin Feinstein, director and president of the non-profit Float Research Collective, which is raising money to conduct more research, said many doctors still hold outdated views about the practice.
“Floating has been referred to as `sensory deprivation,' which I think is a misnomer,” Feinstein said. On the contrary, he said, patients have reported “enhancement” of internal sensations during flotation, such as noticing their breath and heartbeat.
For some individuals, floating can offer profound relief.
After unsuccessful treatments for eating disorders, Emily Noren, 28, of San Diego, tried floating.
At first, she said she found the experience uncomfortable. But after the first 90-minute float she returned for more.
“The float tank helped me to take a break from the real world, a break from my body for a little bit,” said Noren, who has self-published a book, Unsinkable, about the experience. “Before, I'd hear the eating disorder voice, the diet commercial voice, the influencer who lost weight voice, the dad trauma voice. In the float tank, I could hear my own voice.”