There is a nearly indescribable feeling that comes over us in the water. A calmness, a determination, sometimes an invincibility. This is a feeling that is unique to the pursuit of surfing. As science is now learning, it's not an imagined Zen―these effects are not only real, but are proving increasingly beneficial to those living with mental illness and mental health disorders.A 2010 British study sought to test this hypothesis through a six-week study for aspiring surfers between the ages of twelve and twenty-three, with mental illnesses ranging from depression to schizophrenia and psychosis. What they found is that six weeks of surfing was enough to provide not only physical benefit - creating surfers that could stand up and catch waves "at a reasonable standard" ― but also mental benefits, including heightened self-esteem, perceptions of fun, and the ability to stave off negative feelings.A South African organization called Waves for Change also recognized the positive mental changes that could come from time in the water and capitalized on it to grow their program, which combines use of surfing and therapy to tackle mental illness. On a continent where many countries have no access to mental health therapy, this program stands out for creatively addressing a rampant public health worry.Presently, it is the third most pressing health concern in the country (after HIV/AIDS and tuberculosis), but Waves for Change has grown from two surfers to over four hundred while effectively addressing anxiety, depression, and other symptoms of trauma that can seem endemic - some estimates indicate that 1 in 5 children suffer from PTSD.And back Stateside, researcher Ryan Pittsinger of the University of Iowa found that just one half hour surfing unlocked feelings of calm and heightened mood in surveyed Manhattan Beach surfers.So, the positive, mind-calming effects of surfing has been documented well across not just the country, but the world. The question now stands: why? Why does surfing have this effect? A closer look at the sport is showing it may not just be the practice of surfing, but also the chemicals it creates and provokes that make a difference.As with other activities that arouse passion in their participants, surfing elevates two key hormones that counteract powerfully the hormones and neurotransmitters that facilitate mental illness: adrenaline and dopamine. The former raises your heart rate and increases your reaction time (allowing you to progress in the very act of learning to surf); the latter is triggered when you find enjoyment in an activity, making you feel good and confident in what you're doing. But it's not just the internal chemical process that affects mood while surfing."Surf stoke," or the calm but powerful feeling that comes from surfing, increasingly appears to be the result of a chemical reaction happening in the air surrounding waves as they churn and break. The turbulence in the air created by breaking waves leads to the breaking of air and water molecules, releasing charged ions. This release of negatively charged ions has proven to lift the spirits by triggering the release of endorphins and serotonin―hormones and neurotransmitters that affect mood―in the surfer.This domino effect of positive hormone and chemical releases seems to last well after one has left the water, along with an increase of blood flow and circulation of oxygen in the body that would come with any aerobic exercise that one chooses to undertake. Given that running or biking don't provide the same opportunity to churn the all-important ions, surfing seems to be a uniquely healing experience.These skills are particularly important to another group that Pittsinger is working with these days: U.S. Marines who have been diagnosed with combat-related PTSD. His Camp Pendleton-based study, seeking to utilize what he calls "ocean therapy," hopes to help these former soldiers take the lessons of confidence, devotion, and trust, and use them both on the water as they learn to surf and in group discussions to help them address their struggles from during and after their time in combat.Make no mistake, these benefits can come to anyone who chooses to embrace the stoke - not just those seeking to improve their mental health. Bev Sanders, founder of Las Olas Surf Safaris for Women, recognizes its potential to help anyone seeking to center themselves in a society that rarely affords us the permission to slow down: "You have to be forgiving, patient with yourself, and willing to let go. You're really not thinking about anything else and that's hard to come by these days."In many ways, the benefits cited from surfing mimic those cited from a different popular means of treating mental illness: meditation. The presence it requires―you worry about little else, beyond finding the next wave and making it to shore safely - can make it a high-impact, high-thrill alternative to the often touted practice.Mntanywa, one of the South African youth benefiting from South Africa's Waves for Change program, recognizes the importance of that presence in helping him deal with his traumatic past:Just being in the water - away from his family and in a beautiful place - helps him deal with his past. "Pasts don't go away, man. It's always on your mind. But when I'm in the beach," he says, "I always think about the waves."So, if you're near the water, and are in need of a boost, a surprisingly effective way to combat the blues may be hiding just over the next set of waves.