Yoga has become an increasingly popular practice in Western cultures over the past few decades. As more individuals turn to yoga as a means of staying physically fit and stress-free, research has begun to explore the various mental health benefits that yoga may provide. While the physical aspects of yoga such as improved flexibility and core strength have been widely recognized, a growing body of scientific literature now supports the notion that yoga is equally beneficial—if not more so—for one’s psychological and emotional well-being. This paper aims to review the current research on specific mental health conditions that may be positively impacted by a regular yoga practice.
Stress is a near universal modern-day problem that takes both a physical and mental toll. As Western lifestyles become increasingly fast-paced and demanding, more individuals are suffering from stress-related issues such as anxiety, depression, and impaired quality of life (Woodyard, 2011). Yoga has emerged as a popular complementary and alternative therapy for stress management. Several studies have found that yoga reduces perceived stress levels and the physiological stress response. In one randomized controlled pilot study, adults who engaged in either Iyengar or Kundalini yoga classes twice weekly for 8 weeks showed significantly reduced cortisol levels (a physiological marker of stress) compared to a waitlist control group (West et al., 2004). Improvements in mood, self-esteem, energy levels, and coping skills were also reported.
Another randomized controlled trial assessed the effects of 12 weeks of yoga on stress levels in 120 moderately stressed employees (Telles et al., 2012). Participants were randomly assigned to either yoga or a waitlist control group. Those who practiced yoga demonstrated significantly greater reductions in perceived stress, anxiety, and depression compared to controls. Improvements were also seen in stress biomarkers including serum cortisol levels and heart rate variability. Yoga may help relieve stress through its focus on conscious breathing regulation (pranayama), physical postures, and mental relaxation. Practicing yoga provides a soothing experience in which one synchronizes movement with breath to foster mindfulness of the present moment rather than ruminating on worries of the past or future (Woodyard, 2011). For example, holding postures while consciously breathing deeply likely elicits the relaxation response, slowing heart rate and lowering blood pressure, which then reduces the physiological stress response itself.
In addition to reducing stress levels, a regular yoga practice has exhibited antidepressant and anxiolytic effects. In one review of randomized controlled trials examining yoga for depression, yoga was found to be “significantly more effective than inactive controls such as relaxation techniques or no treatment” (Cramer, Lauche, Langhorst, & Dobos, 2013, p. 1). For example, in a 3-armed randomized controlled trial, 81 patients diagnosed with a major depressive episode were randomly assigned to 12 weeks of yoga, antidepressant medication, or a waitlist control group (Sharma et al., 2014). Both the yoga and medication groups demonstrated significantly greater reductions in depression scores on the Hamilton Depression Rating Scale compared to controls at the end of treatment and 3-month follow-up, indicating yoga was similarly effective to medication for improving depressive symptoms. Interestingly, one pilot study found that 8 weeks of Iyengar yoga led to greater decreases in depressed mood, rumination, and maladaptive cognition associated with depression compared to aerobic exercise or a waitlist control (Schumer et al., 2018). The specific postures and breath control in Iyengar yoga may target thought patterns more directly.
Yoga has also demonstrated anxiolytic properties. A review of 7 randomized controlled trials found yoga to be an efficacious intervention for reducing symptoms of anxiety, with “moderate between-group effect sizes for anxiety” compared to controls (Cabral, Meyer, & Ames, 2011, p. 1). For example, one study randomly assigned 102 individuals diagnosed with generalized anxiety disorder to either 12 weeks of twice-weekly Iyengar yoga lessons or a waitlist control (Kirkwood et al., 2005). Compared to controls, the yoga group exhibited significantly greater reductions in anxiety symptoms as measured by the Hamilton Anxiety Rating Scale and the State-Trait Anxiety Inventory. Improvements were maintained at 3-month follow-up. While the mechanisms underlying yoga’s anti-anxiety effects are not fully understood, researchers posit that the mindfulness meditation aspects foster metacognitive awareness to disengage from anxious thoughts, and physical practice paired with conscious breathing reduces physiological arousal.
In addition to stress, depression and anxiety—all common and impairing mental health issues—emerging research suggests yoga may benefit individuals suffering from other conditions such as PTSD, ADHD, and schizophrenia. For example, a growing body of literature supports yoga as an efficacious complementary therapy for PTSD (Staples, Hamilton, & Uddo, 2013). A recent systematic review of 11 randomized controlled trials demonstrated moderate to large effect sizes for yoga versus inactive controls in reducing PTSD symptoms including re-experiencing, avoidance, negative cognitions and mood, and arousal (Dick et al., 2014). Yoga may help regulate stress reactivity and target avoidance behaviors associated with PTSD (Staples et al., 2013).
Preliminary findings also indicate potential benefits of yoga for children and adults with ADHD. One recent randomized controlled trial found that an 8-week yoga intervention improved ADHD symptoms and behavioral conduct compared to a waitlist control in 50 elementary school children with ADHD (Hariprasad et al., 2013). This was one of the first controlled trials to study yoga’s effects on ADHD. Research on the application of yoga for schizophrenia is limited but emerging. A few feasibility and case studies point to possible improvements in positive and negative symptoms, mental focus, and self-esteem (Duraiswamy et al., 2007; Piet & Hougaard, 2011). Adequately powered randomized controlled trials are still needed before definitive conclusions regarding the effectiveness of yoga for schizophrenia can be drawn. Overall, though research is nascent, yoga’s mindfulness components coupled with its ability to reduce nervous system arousal suggest it holds promise as a therapeutic option to explore further in these populations.
Scientific evidence has documented various mental health benefits associated with a regular yoga practice. Yoga has been shown effective at reducing perceived stress as well as physiological stress indicators such as cortisol levels. Furthermore, yoga demonstrates antidepressant and anxiolytic properties comparable to other first-line treatments. Preliminary positive findings have also emerged for additional mental health conditions including PTSD, ADHD, and schizophrenia. Mechanisms underlying yoga’s therapeutic effects likely include stress reduction, mindfulness cultivation, and alteration of cognitive/emotional processes through both physical postures and breath awareness. More research is still needed, particularly randomized controlled trials with larger sample sizes. Current evidence supports yoga as a valuable complementary option or adjunct to mainstream care for improving a variety of mental health issues. With its growing popularity and accessibility in the West, yoga shows promise as an empowering self-care tool that patients may readily incorporate into their daily lives to foster greater well-being.
Andrew Stroud