Everything in the universe is pulsating and vibrating – nothing is really standing still! The sound Om, when chanted, vibrates at the frequency of 432 Hz, which is the same vibrational frequency found throughout everything in nature.
As such AUM is the basic sound of the universe; so by chanting it we are symbolically and physically tuning in to that sound and acknowledging our connection to all other living beings, nature and the universe.
In addition the vibrations and rhythmic pronunciation also have a physical affect on the body by slowing down the nervous system and calming the mind similar to meditation. When the mind is relaxed, your blood pressure decreases and ultimately the health of your heart improves.