RESUMO
BACKGROUND: This study assessed efficacy of plant based bioequivalent nitrate complex, consist of vitamins, natural antioxidants and phytophenol rich food extracts to elevate nitric oxide (NO) bioavailability as determined by saliva conversion of nitrate (NO3-) to nitrite (NO2-) a required step to produce NO, in relationship to lowering blood pressure (BP) in both men and women. METHODS: 67 individuals (26 men; mean age of 59.3 ± 9.0 yrs) with mean baseline systolic and diastolic BP >120 and 80 mmHg respectively were randomized to receive daily dosing of 314 mM NO3- or NO3- free (placebo) tablets in double-blinded study for 12 weeks (wks). Inorganic NO3- tablets consist of NO3- rich beetroot extract, thiamine nitrate, and potassium nitrate in the presence of ascorbic acid, to facilitate NO bioavailability. RESULTS: The primary endpoint of the study was reduction in BP at 12 wks by improving endothelial function. At study conclusion, mean ± SD reduction in systolic BP (SBP) in the inorganic NO3- group was 12.5 ± 13.3 mmHg (p = 0.0007), as compared to 6.19 ± 11.39 mmHg (p = 0.004) in the placebo group, for a placebo-corrected reduction of -6.31 mmHg (95% CI 10.89-2.31, p = 0.04). NO3- also reduced diastolic BP by 4.7 ± 10.3 mmHg (p = 0.01), while no significant reduction in placebo group (1.98 ± 9.38 mmHg, p = 0.24) was noted. Endothelial function improved at 12 weeks by 0.8 ± 3.1 (p = 0.03) in active group when compared to 0.1 ± 1.8 (p = 0.82) in placebo group. CONCLUSION: Endothelial function improved robustly reducing both systolic and diastolic BP in hypertensive individuals with daily supplementation of dietary NO3-. CLINICALTRIALS. GOV ID: NCT03909789.