Induction of salivary nerve growth factor by yogic breathing: A randomized controlled trial - Balasubramanian et al. (2015)
Key Points
Nerve growth factor (NGF) is found in saliva, and relaxation/yogic breathing/slow breathing stimulates saliva production
NGF is significantly increased in the saliva of subjects who perform 20 minutes of yogic breathing compared to controls
The Breathing Diabetic Summary
If you sit, relax, and breathe slowly, you will notice your mouth begin to water. I use this as a indicator that I dropped into deep relaxation during my slow breathing practice. It turns out that this “side effect” of relaxation might not be a side effect at all, but a therapeutic benefit.
Twenty healthy volunteers were broken into two groups: 10 were given instructions in yogic breathing and 10 were simply told to read an article for 20 minutes. The yogic breathing group started out with 10 minutes of Om chanting followed by 10 minutes of a specific breathing practice called Thirumoolar Pranayamam, which is an alternate nostril breathing technique in which one inhales through the left nostril for 2 sec, holds for 8 seconds, and exhales through the right nostril for 4 seconds. The process is then repeated with the nostrils reversed. The scientists measured nerve growth factor (NGF) in the saliva of the participants just before starting the breathing (or reading for the controls) and after 20 minutes.
NGF increased significantly after the yogic breathing, whereas it remained almost unchanged in the control group. Statistical modeling of the results indicated that yogic breathing increased NGF 7.7 points more than reading an article. The authors suspect that the NGF stimulated by yogic breathing could be transferred to the central nervous system through the oral organs or by sublingual absorption into the bloodstream.
A quick Google search and Wiki article highlights the importance of these findings:
“…numerous biological processes involving NGF have been identified, two of them being the survival of pancreatic beta cells and the regulation of the immune system.”
There is still a lot of research to be done to understand the therapeutic role of NGF produced in the saliva. However, I think these results are very encouraging. They might also help explain why taping up at night and waking up with a moist mouth results in deeper, more restorative sleep. I am excited to see what future studies show us about saliva stimulated by relaxation.
Journal Reference:
Sundaravadivel Balasubramanian, Jacobo E. Mintzer, and Amy E. Wahlquist (2015), Induction of salivary nerve growth factor by yogic breathing: A randomized controlled trial, International Psychogeriatrics, 27 (1), 168 – 170.