Tea Effects on Blood Pressure

Tea Effects on Blood Pressure
Epidemiological investigations have shown that tea consumption may exert a lowering effect on blood pressure. A survey of adults in China that average rate of hypertension in the group who drank tea as a habit was lower than that in the group who did not.

A clinical investigations on patients with hypertension revealed that a 10 g daily intake of green tea for half a year resulted in reduction of the blood pressure by 20-30%.

Oral administration of tea polyphenols also yielded a decrease of blood pressure in patients, a number of studies also revealed the blood pressure decreasing effects of tea in experimental animal models.

The reported active substance include tea extracts, polyphenols and tea tannin.

In addition, theanine, the amino acid component of tea, was found to be effective in decreasing the blood pressure of spontaneous hypertensive rates.

Caffeine may exert a variable effect on blood pressure. Intravenous administration of caffeine may cause an initial fall in blood pressure and then a secondary rise.

So, caffeine should be taken into account if whole tea preparation instead of tea component is used in studying the effect on blood pressure.
Tea Effects on Blood Pressure

Drinking tea can reduce high blood pressure

A study (published Archives of Internal Medicine 2012) of 95 patients from Western Australia suggested that drinking three cups a day of black tea can reduce blood pressure by 2-3 mmHg in both systolic and diastolic blood pressure.

Black tea is a good source of flavonoids. Flavonoids protect LDL cholesterol from oxidation, and this can reduce the risk of atherosclerosis, stroke, hypertension and heart attack.

Oral administration of tea polyphenols also yielded a decrease of blood pressure in patients. The reported active substances include tea extracts, polyphenols and tea tannin. Tea tannins (2 to 4 mg orally) could reduce the systolic blood pressure in rats. Investigation proved that tea components, especially TFDG and EGCG showed beneficial effect.

In addition, theanine, an amino acid found in tea produces a calming effect on the brain. It induces a feeling of relaxation and was found to be effective lowers the blood pressure of spontaneous hypertensive rates.

Tea polyphenols and caffeine may also ameliorate the development of hypertension by improving the renal circulatory state as a result of its direct action on the kidney, including the activation of the kinin-kallikrein-prostaglandin system in the kidney.
Drinking tea can reduce high blood pressure