Yoga for Depression: the research evidence

Yoga for Depression
By Kelli Foulkrod
 




We all know that practicing yoga makes you feel good, but did you know that science is now beginning to demonstrate evidence that a consistent yoga and meditation practice is also an effective treatment for depression?  Scientists think yoga works by regulating the nervous system by increasing vagal tone and supports the body’s ability to successfully respond to stress by practicing meditation and breathing practices to calm the mind. 
 
Let’s break down the healing benefits yoga has on the nervous system by examining the evidence.  There is now a growing body of scientific research studies to support the use of yoga and meditation in the treatment of depression.

1. Decreases depressive symptoms – Woolery et al., 2004 found in a group of young adults that the yoga group demonstrated a significant decrease in depressive symptoms and state trait anxiety.  Also, Uebelacker et al, 2017 did a randomized controlled trial in a group with persistent depression and found that the yoga group reported fewer depressive symptoms over the 6 month follow period, and had better social and role functioning.
2. Increases GABA – Streeter et al., (2010) showed in a pilot study that increases in GABA activity were found in the brains of the group with a consistent yoga practice.   GABA is of course the most abundant calming neurotransmitter and low levels have been linked to anxiety and depression.   
3. Lowers cortisol  - Kamei et al., (2000) demonstrated decreases in serums cortisol during a yoga practice and hypothesized that this was related to alpha brain wave activation.  Cortisol is the stress hormone that when released chronically has been linked to lower levels of serotonin and dopamine in the brain.
4. Increases self-esteem and well-being - Goldstein et al., (2016) found that young adults had significant increases in self-esteem and sense of well being and empowerment after completing a yoga and breathing group.
5. Increased heart rate variability – Tyagi & Cohen, (2016) Meta-analysis suggest that yoga can affect cardiac autonomic regulation with increased HRV and vagal dominance during yoga practices.  Depression has been previously linked to low heart rate variability in cardiac patients. 
6. Anti-inflammatory effects - Kaliman et al (2014) found enhanced genomic expression of anti-inflammatory genes and suppression of inflammatory in a group of expert meditators.  There is a theory in functional medicine which suggests that the negative mood symptoms of anxiety and depression are actually a by product of the body’s innate alarm system, altering the individual of immune system activation due to inflammation in the body.  Therefore, current researchers are now exploring the correlation between high levels of inflammatory cytokines and mental health symptoms.
7. Vagal nerve tone - Kalyani, et al., (2011) using functional magnetic resonance imaging (fMRI) researchers showed that chanting OM deactivated the limbic system, which is similar to the effects of vagus nerve stimulation treatments used for depression. 
8. Addresses trauma – Rhodes et al., (2016) 60 women with chronic PTSD in a long term follow up study found that those with a consistent yoga practice, demonstrated greater decreases in PTSD symptom severity and depression symptoms.
9. Reduces anxiety and worry – Hylander, F., et al. (2017) Found significant reductions in anxiety symptoms and worry when using a combination of mindfulness and yin yoga. 
10. Balances blood sugar – Chimkode et al., (2015) yoga group over a 2-year period found to have lowered high blood sugar levels in patients with type 2 diabetes.  Hypoglycemia has been repeatedly connected to a wide range of mental and emotional symptoms such as anxiety and significant sadness.

 
With the growing mountain of research evidence supporting the use of yoga for mental health benefits, it is worth considering as a treatment option for those looking for alternatives to pharmaceuticals or looking to take less pharmaceuticals.  Just as one would take a pharmaceutical daily, it is recommended that yoga and meditation be practiced consistently in order to see the full benefits of the practice.  Yoga is dose dependent, meaning the more you do, the better you will feel!

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