A double-blind placebo-controlled study of the effectiveness and tolerability of oral stevioside in human hypertension

Aims Stevioside is a natural plant glycoside isolated from the plant Stevia rebaudiana which has been commercialized as a sweetener in japan for more than 20 years. Previous animal studies have shown that stevioside has an an tihypertensive effect. This study was to designed to evaluate the effect of stevioside in human hypertension. Methods A multicentre, randomized, double-blind, placebo-controlled study w as undertaken. This study group consisted of 106 Chinese hypertensive subje cts with diastolic blood pressure between 95 and 110 mmHg and ages ranging from 28 to 75 years with 60 subjects (men 34, women 26; mean +/- s.d., 54.1 +/- 3.8 years) allocated to active treatment and 46 (men 19, women 27; mea n +/- s.d., 53.7 +/- 4.1 years) to placebo treatment. Each subject was give n capsules containing stevioside (250 mg) or placebo thrice daily and follo wed-up at monthly intervals for 1 year. Results After 3 months, the systolic and diastolic blood pressure of the st evioside group decreased significantly (systolic: 166.0 +/- 9.4-152.6 +/- 6 .8 mmHg; diastolic: 104.7 +/- 5.2-90.3 +/- 3.6 mmHg, P < 0.05), and the eff ect persisted during the whole year. Blood biochemistry parameters includin g lipid and glucose showed no significant changes. No significant adverse e ffect was observed and quality of life assessment showed no deterioration. Conclusions This study shows that oral stevioside is a well tolerated and e ffective modality that may be considered as an alternative or supplementary therapy for patients with hypertension.