Talking about breathing, it was found that it can also control high blood pressure. It was reason that the body automatically response to poor oxygen level in the blood by pumping out more blood. Simple logic is to increase the pressure... so there goes high blood pressure. Now, don't believe me, go to google and enter the key words "High Blood Pressure Breathing" and you will get load of information.
Here is my evidence:
Before I started my breathing, it was 135/90. After breathing exercise for one minute, it drop to the above!
This seems to work even if you are currently on drug. So, if you have HiBP, try it. If you have no HiBP, try it anyway because slow breathing is good for you.