Dr, Benson states, “the elicitation of the relaxation response - can be traced back to the earliest civilizations. It appears that one of our most basic bodily avenues to better health is the simple following of the breath, in and out, and the avoidance of distracting thoughts”.

Russill Paul says, “Vocal sound production is also known to affect the vagus nerve, which is the single most important nerve in the body. This nerve passes through the neck and services the heart, the lungs, intestines and intestinal tract and back muscles. It has also been determined, through the phenomenal work of molecular biologist Candice Pert, that emotional toxicity can remain lodged in the neuropeptides that line the walls of our intestines, particularly since most of the time we breathe shallow.  Since chanting naturally embodies cycles of deep respiration, a significant amount of this emotional toxicity can be released from the body, which is why people enjoy it so much. Chanting is therefore a sort of “Divine therapy,” a means of cleansing the soul of unwanted psychic residue, and a process that has corresponding physiological effects.”

Jon Lundberg and Eddie Weitzberg discovered that humming can help to ventilate and open the sinuses., They found that humming increased nitric oxide levels fifteen fold, compared to quiet exhalations without sound. The exhalations of people with healthy sinuses tend to have high nitric oxide levels, meaning  that more air is able to flow between the sinuses and the nose.

The two researchers defined humming simply as exhaling with sound while the mouth is closed; they say that chanting "Om" produces the same effects. Chanting and humming both create sound vibrations, which encourage air to move back and forth between the sinus membranes and nasal passages. This air movement then opens tiny ducts, or ostia, that connect the nose to the sinuses, allowing sinuses to drain properly.

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