Another herb which can help reduce high blood pressure naturally is Stevia rebaudiana. Stevia is a tropical perennial shrub which is widely cultivated for its sweet leaves.
Background: Stevia rebaudiana is a tropical perennial shrub originally native to Paraguay which has leaves which are 10-15 times sweeter than sugar. The native peoples of South America still use this herb as a heart tonic, a diuretic, and as a remedy for heartburn. It can be found growing wild in mountainous regions of southern South America today and is cultivated commercially in a number of different countries, including Brazil and China.
Description: A shrubby tropical perennial which can be grown to a height of 12 to 15 inches in one season in 6 inch pots. The soft, pale green stems bear ovate, serrated leaves up to one inch long as well as clusters of tiny white flowers in the wintertime.
Cultivation: Stevia does best in a warm, partly shaded location with damp (but well drained) acidic soil. It is easily started by sowing seed into a growing tray placed on a heating mat set to 80 degrees F in the greenhouse in the springtime. Given the right set of conditions, Stevia can be a remarkably fast grower.
Parts Used: leaves
Harvest: the leaves may be picked at any time and used fresh, or dried and ground into a powder which can be used as a natural, non- caloric sweetener.
Research: Clinical studies have demonstrated that Sweet Herb (Stevia rebaudiana) can lower blood pressure in humans. A study published in the British Journal of Clinical Pharmacology [i] in 2000 showed that Stevia significantly decreased blood pressure in hypertensive human subjects in a randomized, double-blind study. Participants who received 250 mg of stevioside (a chemical compound in Stevia responsible for its sweetness) three times daily for one year averaged a reduction of 9.4-6.8 mm Hg (systolic) and 5.2-3.6 mm Hg (diastolic) in their blood pressure readings. Another study [ii] in 2006 using human subjects confirmed these results. Test participants in this study were given differing amounts of stevia for up to 11 weeks. Those receiving at least 15 mg/kg/day showed a marked decrease in their blood pressure readings over a six week period. (Note: These human studies also confirm earlier Brazilian studies [iii] which reported that Stevia lowers blood pressure in rats.)
Footnotes:
[i] Chan P., et al: A double-blind placebo-controlled study of the e ffectiveness and tolerability of oral stevioside in human hypertension. Br J Clin Pharmacol 50(3):215-220, 2000.
[ii] Ferri LA, et al. Investigation of the antihypertensive effect of oral crude stevioside in patients with mild essential hypertension. Phytother Res. Sep;20(9):732-6.2006
[iii] Melis MS, Sainati AF. Effect of calcium and verpanim on renal function of rats during treatment with stevioside. J. Ethnopharmacol. 11:257-262 1991