Table 2.

The effects of dietary inorganic nitrate on blood pressure in patient population studies

Author	Participants	BP primary or secondary endpoint	Primary endpoint	Secondary endpoint	Nitrate source/dose	Placebo	Effect on BP	BP measurement method	Study design	Intervention length
Bondonno et al. [86•]	Hypertensive (10 M, 17 F) mean age 63 years	Primary	BP	HR, plasma and salivary nitrite/nitrate, urinary Na+, K+ and creatinine	5.5 mmol/day beetroot juice	Nitrate-depleted beetroot juice	No effect	ABPM and home BP	Randomized, double-blind, placebo-controlled, crossover (2-week washout)	Chronic 1 week
Kapil et al. [87•]	Hypertensive (64 F) mean age 56 years (ctl) and 58 years (NO3−)	Primary	BP	HR, FMD, PWV, plasma, salivary and urinary nitrite/nitrate, plasma cGMP	6.4 mmol/day beetroot juice	Nitrate-depleted beetroot juice	Clinic −7.7/2.4 mmHg (P < 0.050). 24-h ABPM −7.7/5.2 mmHg (P < 0.001 for both). Home −8/3.8 mmHg (P < 0.001, P < 0.01)	Clinic, ABPM and home BP	Randomized, double-blind, placebo-controlled, crossover (2-week run-in)	Chronic 4 weeks
Bondonno et al. [88]	Pre-hypertensives (12 M, 26 F) mean age 61 years	Primary	BP, PWV, augmentation index	HR, plasma and salivary nitrite/nitrate	6.45 mmol/day nitrate-rich vegetables	Low-nitrate vegetables	SBP (NS), DBP (NS)	Clinic, ABPM and home BP	Randomized, placebo-controlled, crossover (7-day washout)	Chronic 1 week
Jajja et al. [89•]	Overweight, older (12 M, 9 F) mean age 62 years	Primary	BP	Salivary and urinary nitrite/nitrate	4.84–6.45 mmol/day (conc beetroot juice)	Blackcurrant juice	Daily SBP −7.3 mmHg during final week (P = 0.02), DBP (NS)	Clinic, ABPM and home BP	2-arm, parallel, randomized clinical trial	Chronic 21 days
Ghosh et al. [70]	Grade 1 hypertensives n = 15 (M and F) mean age 53 years	Primary	BP, PWV	HR, Plasma nitrite/nitrate and cGMP	3.3 mmol beetroot juice	Water	SBP −11.2 mmHg (P < 0.001), BP −9.6 mmHg (P < 0.001)	Clinic	Randomized, open-label crossover	Acute 24 h
Gilchrist et al. [90]	Type 2 diabetics (18 M, 9 F) mean age 67 years	Primary	BP, microvascular endothelial function, isoglycemic clamp	Plasma nitirte/nitrate	7.5 mmol beetroot juice	Nitrate-depleted beetroot juice	No effect	ABPM	Randomized, double-blind, placebo-controlled, crossover (4-week washout)	Chronic 2 weeks
Kelly et al. [91•]	Older, (6 M, 6 F) mean age 64 years M, 63 years F	Primary	BP, O2 uptake kinetics, and muscle (e.g. PCr) and cognitive function	HR, plasma nitrite/nitrate	9.6 mmol/day (conc beetroot juice)	Nitrate-depleted beetroot	SBP −5 mmHg (P < 0.05), DBP −3 mmHg (P < 0.05)	Clinic	Randomized, double-blind, placebo-controlled, crossover (72-h washout)	Chronic 3 days
Kenjale et al. [92•]	Peripheral artery disease (4 M, 4 F) mean age 67 years	Secondary	Exercise performance (e.g. VO2 and muscle PCr)	BP, HR, Plasma nitrite/nitrate, vascular testing	9.1 mmol beetroot juice	Orange juice	SBP −18 mmHg (P < 0.05) 2-min post exercise, DBP −8 mmHg (P < 0.05) at rest and during exercise	Clinic	Randomized, double-blind, placebo-controlled, crossover (7–14-day washout)	Acute 4 h

Table summarizing the methods and findings of clinical studies investigating the effects of inorganic nitrate on blood pressure (BP) in various patient populations, including hypertensive, diabetic and peripheral artery disease patients as well as older and/or overweight individuals. Study information includes participant information (M male, F female), primary and secondary study end points (BP blood pressure, FMD flow-mediated dilatation, PWV pulse wave velocity), nitrate and placebo sources and doses, summary of effects on systolic (SBP) and diastolic (DBP) blood pressure, blood pressure method of measurement (clinic, home or ambulatory (ABPM) blood pressure monitoring), study design and intervention length (acute or chronic). Numbers for referencing purposes are found in [square brackets]