Many of the blood pressure drugs, the "alpha and beta-adrenergic inhibitors" function by interrupting the action of adrenalin, which stimulates the body to "fight or flight," and can increase the blood pressure in many people.
Meditation works in almost the same way. While one is doing meditation, one has a break from the chaotic thoughts and anxieties felt in daily life which cause the body to create adrenalin, and other excitatory physic-chemicals. The body has the time to return to homeostasis, that is, to rebalance. If an individual meditates once or twice every day, the rebalancing effect is greatly improved.
The mind is often and fittingly called "a drunken monkey," because of the continuous clamor of disorderly thought and internal dialogue. Meditation silences the monkey, thus giving the body the capability to heal itself.
"The Relaxation Response" a book written in 1975 by Herbert Benson, a Harvard physician, and Miriam Z. Klipper states that those who meditated on the word "one" had lower blood pressure, among other physical and psychological benefits. This was treated as an important medical discovery which was funny, since Easterners have used this method for many millennia.
Of course, the principal benefit of yoga meditation is the boost and growth of consciousness, sometimes to a godly degree. It is often said that when a person prays, one speaks to God, but when one meditates, one listens to God.