But there's growing belief that being near, on, in, or under water has a far more powerful impact on our mental, and physical health than we might realise.
The "Blue Mind" ethos, which is the subject of growing European research, is being championed by Californian biologist and researcher Wallace J Nichols, who tells us he believes "the idea that water is medicine will be quite mainstream" within 10 years.
Here we meet some of the people who are already using the power of water to improve their mental health.
"Clean, healthy water is a fundamental and free health resource to us. It is underutilised and undervalued."
Read more here.