A recent pilot study suggests that humming - Bee Breath in Yoga Classes - can physiologically reduce stress.
(Do read the full study below)
Bhramari Pranayama has long been said to calm the mind and slow the heart rate but now a new small study (April) 23) peer reviewed, of 23 people suggest that this could be true.
HRV - Heart Rate Viability was measured for physical activity, emotional stress, sleep and humming. The stress index was lowest in those that did the humming which suggest that humming is better at lowering stress than physical active or sleep. It does this by enhancing the parasympathetic nervous system and reducing the sympathetic nervous system. The current thought is that it stimulates the vagus nerve - that is cranial nerve X that controls heart rate, blood pressure, bloating, dizziness and much else.
Stress is well known to affect disease progression and increase the risk of heart disease. Stress may affect the onset of diabetes and is associated with greater amounts of depression in people. It may make breathing conditions worse and affect sleep.
The link between stress, the autonomic nervous system and HRV is well documented. Slow breathing may show that HRV can be increased and Heart Rate HR goes down.
Humming has been associated with lower HR, increased concentration, better focus and attention as well as better sleep quality and lower stress levels.
As a yoga teacher of 23 years I have found the result of Bee Breath - humming -very calming and so have many of my students over the years. Limitations are that this pilot study is very small and is a pilot so more work could be done in this area but there are no side effects to humming so why not try a daily practice to see if it works for you.
Pub. Med. Central
Trivedi G, Sharma K, Saboo B, Kathirvel S, Konat A, Zapadia V, Prajapati PJ, Benani U, Patel K, Shah S. Humming (Simple Bhramari Pranayama) as a Stress Buster: A Holter-Based Study to Analyze Heart Rate Variability (HRV) Parameters During Bhramari, Physical Activity, Emotional Stress, and Sleep. Cureus. 2023 Apr 13;15(4):e37527. doi: 10.7759/cureus.37527. PMID: 37193427; PMCID: PMC10182780.
https://www.ncbi.nlm.nih.gov/pmc/articles/PMC10182780/#:~:text=Humming%20(simple%20Bhramari)%20can%20be,and%20slow%20down%20sympathetic%20activation.