In recent years, the yoga craze has been growing across the U.S. According to a study published in Yoga Journal Magazine in 2008, 15.8 million people (6.9 percent of American adults) practice yoga.
What’s more, the study also reported that 6.1 percent of Americans have had a doctor or therapist recommend yoga to them.
So why would so many medical professionals be recommending the practice? How could yoga be connected to your mental, not just physical, health?
According to the Mayo Clinic, the practice of yoga, which has ancient roots in India, is today considered “a mind-body type of complementary and alternative medicine practice that brings together physical and mental disciplines to achieve peacefulness of body and mind.”
There are a wide variety of types and styles of yoga, but the most common is Hatha yoga. Typical yoga classes offered today are based on Hatha yoga and consist of two main components: postures and breath.
The physical poses range greatly in difficulty and intensity and often include series of movements in repetition. These postures are aimed at improving flexibility and increasing strength in the body.
Awareness and control of breathing is used as a practice for eventually controlling and calming the body and mind. As the Mayo Clinic puts it, “in yoga, breath signifies your vital energy” and is a key element of the practice.
Mental Health Connection
It is not necessarily obvious how all these poses and breathing could relate to mental health. However the Harvard Medical School (HMS) reports that despite the unknowns, yoga has been shown to potentially help regulate stress, anxiety and depression.
According to HMS, yoga can affect stress by easing perceived stressors and anxiety, thus affecting stress response systems and physiological arousal. Through this process, heart rate and blood pressure can both be lowered, and respiration calmed.
Furthermore, HMS reports that “there is also evidence that yoga practices help increase heart rate variability, an indicator of the body's ability to respond to stress more flexibly.”
In terms of depression and mood, yoga might affect these factors through similar channels as other forms of both exercise and relaxation techniques, as the practice combines these two activities.
The Mayo Clinic reports that a mood boost from yoga may also be due to its potential to improve sleep problems and fatigue through relaxation and stress release.
Yoga and the Brain
A 2010 study published in the Journal of Alternative and Complementary Medicine took these ideas a bit further by examining how gamma-aminobutyric (GABA) levels are affected by yoga versus other exercise (in this case, walking).
According to the authors, led by Chris Streeter, MD, low GABA levels are known to be connected to mood and anxiety disorders, like depression.
The study followed 34 healthy adults aged 18 to 45 and monitored both overall psychological state (through self-reports) and GABA levels (through brain scans) over a 12 week period.
The subjects were randomized into two groups, one group who practiced yoga for 60 minutes three times weekly, and one group who walked for 60 minutes three times weekly.
At the conclusion of the study, the authors found that “the yoga intervention was associated with greater improvements in mood and decreases in anxiety...compared to the metabolically matched walking intervention, suggesting that the effect of yoga on mood and anxiety is not solely due to the metabolic demands of the activity.”
Not only was mood improved, these positive changes correlated with an increase in GABA levels, showing a possible connection between GABA levels, yoga and mental health, beyond the normal interaction between exercise and mood.
This was a small study and broader research should be done before specific conclusions are drawn, but it does expand on hypothesis as to why some people find yoga so beneficial to their happiness and state of mind.
Yoga and Youth
As more research like Dr. Streeter’s GABA study is completed, we could see a change in yoga’s role in U.S. culture. Some are predicting that the presence of yoga in schools could increase, based on studies examining yoga and the mental health of adolescents.
One such preliminary study, led by Jessica Noggle, PhD, was published in the April 2012 edition of the Journal of Developmental & Behavioral Pediatrics and explored both yoga’s effect on teen mental wellness and the feasibility of introducing yoga as a part of school curriculum.
This small study followed 51 U.S. students in their final two years of high school over a ten week period. Students were randomized into two groups, who either attended a normal PE class or a yoga class several times a week.
Based on the self-reported results, mood improved in the yoga group as compared to the PE group on a variety of different scales (including the Profile of Mood States and Inventory of Positive Psychological Attitudes), as did stress levels.
The program was also generally well received by the students, suggesting that yoga as school curriculum is a feasible possibility.
This study was small, and some problems with attendance were noted, but according to the authors, the results show cause for further exploration both into yoga and teen mental health and yoga programs in schools.
As the popularity of the practice continues to grow, there is no doubt that more and more research will be completed and more questions answered as to how yoga can affect mental wellness.
In the meantime, when your spirits are down, it might be worth trying out a downward-facing dog to see if you feel any mental benefits.