The long-term intake of green tea was associated with improved blood pressure levels. Studies suggest drinking 3 to 4 cups of the tea to help regulate blood pressure.
One study also stated that as a result of lowered blood pressure (due to green tea consumption), participants saw a reduction in coronary heart disease risk by 5 percent and stroke risk by 8 percent (8).
Blood pressure is usually caused by angiotensin-converting enzyme (or ACE), an enzyme secreted by the kidneys.
Most drugs for blood pressure act as ACE inhibitors. But green tea, unbelievably, is a natural ACE inhibitor. It prevents the action of this enzyme and helps lower blood pressure (9).