Dietary inorganic nitrate supplementation reduces central blood pressure, aortic stiffness, and blood pressure responsiveness in older adults

Aging is associated with increased aortic stiffness and exaggerated stress-induced blood pressure (BP) responsiveness, both of which contribute to the risk of cardiovascular disease. Supplementation with inorganic nitrate increases nitric oxide (NO) bioavailability and is a promising potential treatment to improve vascular function. While the acute effects of dietary inorganic nitrate supplementation on various measures of vascular function and BP have been demonstrated in several studies, the effects of increasing NO bioavailability through prolonged use (i.e. weeks) is unclear. Therefore, we tested the hypothesis that 4-weeks of inorganic nitrate supplementation will effectively increase NO bioavailability (as measured by plasma nitrate and nitrite) and reduce central BP, aortic stiffness, and BP responsiveness to a cold pressor test (CPT) in older adults. Thirteen older adults (67±3 years; 7 males and 6 females) completed a randomized, double-blind, placebo-controlled, crossover trial consisting of two 4-week supplementation periods (nitrate vs. placebo) separated by a 4-week washout. Central BP and carotid-femoral pulse wave velocity (cfPWV) were measured via applanation tonometry. Peripheral BP responses were assessed using beat-by-beat BP at baseline and during CPT. Plasma nitrate (40±24 to 76±46 µM, P0.05 for all). Additionally, the peak change (Δ from baseline) in peripheral SBP (28±10 to 23±6 mmHg, P< 0.05) and mean arterial pressure (MAP; 17±6 to 14±3 mmHg, P< 0.05) during the CPT were reduced following nitrate with no changes observed after placebo (SBP 25±8 to 26±12 mmHg, P=0.51; MAP 14±4 to 16±8 mmHg, P=0.19). Our findings demonstrate 4-weeks of inorganic dietary nitrate supplementation has favorable effects on central BP, aortic stiffness and BP responsiveness in older adults. This abstract was presented at the American Physiology Summit 2026 and is only available in HTML format. There is no downloadable file or PDF version. The Physiology editorial board was not involved in the peer review process.