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Cited by 375Blood Pressure and Hypertension StudiesNitric Oxide and Endothelin EffectsCardiovascular Health and Disease Prevention

Inorganic Nitrate and Beetroot Juice Supplementation Reduces Blood Pressure in Adults: A Systematic Review and Meta-Analysis

Open access
Siervo, Mario, Lara, Jose, Ogbonmwan, Ikponmwonsa, Mathers, John C.·2013·The Journal of Nutrition
DOI 10.3945/jn.112.170233
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Abstract

Diets including food products rich in inorganic nitrate are associated with lower blood pressure (BP). The evidence for the BP-lowering effects of inorganic nitrate and beetroot in randomized clinical trials has not been systematically assessed. The objective was to conduct a systematic review and meta-analysis of randomized clinical trials that examined the effects of inorganic nitrate and beetroot supplementation on BP. Medline, EMBASE, and Scopus databases were searched from inception to February 2013. The specific inclusion criteria were: 1) randomized clinical trials; 2) trials reporting effects on systolic or diastolic BP or both; and 3) trials comparing inorganic nitrate or beetroot juice supplementation with placebo control groups. Random-effects models were used to assess the pooled BP effect sizes. Sixteen trials met the eligibility criteria for the systematic review. All studies had a crossover study design. The trials were conducted between 2006 and 2012 and included a total of 254 participants with 7-30 participants/study. The duration of each intervention ranged from 2 h to 15 d. Inorganic nitrate and beetroot juice consumption were associated with greater changes in systolic BP [-4.4 mm Hg (95% CI: -5.9, -2.8); P < 0.001] than diastolic BP [-1.1 mm Hg (95% CI: -2.2, 0.1); P = 0.06]. The meta-regression showed an association between daily dose of inorganic nitrate and changes in systolic BP (P < 0.05). Inorganic nitrate and beetroot juice supplementation was associated with a significant reduction in systolic BP. These findings need to be tested in long-term trials and in individuals at greater cardiovascular risk.

AI snapshot

Written from the paper’s full text.

TL;DR

This systematic review and meta-analysis of 16 randomized crossover trials found that inorganic nitrate and beetroot juice supplementation lowered systolic blood pressure in adults, with a smaller and statistically nonsignificant diastolic effect. The evidence was short-term and drawn mostly from young, healthy men, so long-term and clinical-population benefits remain uncertain.

Key findings

  • Pooled systolic blood pressure fell by 4.4 mm Hg (P < 0.001), while the pooled diastolic change was −1.1 mm Hg (P = 0.06), as reported in the paper’s discussion and abstract.
  • Beetroot juice and inorganic nitrate salts produced similar systolic reductions: −4.5 mm Hg and −4.2 mm Hg, respectively (both P < 0.001); neither intervention significantly changed diastolic blood pressure in subgroup analyses.
  • Meta-regression showed that a higher daily inorganic nitrate dose was associated with greater systolic blood pressure reduction (P < 0.05), but study duration and plasma nitrite concentration were not significantly associated with systolic or diastolic changes.
  • Heterogeneity was high for systolic blood pressure (I² = 66%) and moderate for diastolic blood pressure (I² = 45%); Egger’s test did not indicate publication bias (P = 0.47).

Methods

  • Systematic review and meta-analysis following PRISMA, searching Medline, EMBASE, and Scopus from inception to February 2013 for randomized clinical trials comparing inorganic nitrate or beetroot juice with placebo in adults.
  • Sixteen crossover trials met inclusion criteria, conducted between 2006 and 2012, including 254 participants (7–30 per study), with intervention durations from 2 h to 15 d and washout periods from 6 to 28 d; 16 trials contributed to systolic and 13 to diastolic meta-analyses.
  • Random-effects DerSimonian–Laird models estimated pooled mean differences in blood pressure; sensitivity analyses examined imputed pre-post correlations, study duration, intervention type, exclusion of exercise-performance studies, and potential publication bias, with meta-regression for nitrate dose, duration, and plasma nitrite.

Limitations

  • The paper states that the trials had small samples, short intervention periods, and mostly recruited young, healthy, nonsmoking men, limiting applicability to women and to people with cardiovascular or metabolic disease; long-term maintenance of effects is unknown.
  • The authors note that restricting the search to English-language, peer-reviewed articles may have increased publication bias, and that the meta-analysis relied on retrospective inference, imputed pre-post correlations, and limited access to individual participant data.
  • The paper also reports that one abstract-only study was included qualitatively but excluded from the meta-analysis, and that trials using 24-h ambulatory blood pressure monitoring did not confirm the beneficial effects seen with resting blood pressure; the text makes evident that several included studies primarily examined exercise performance rather than blood pressure.

Model-written summary. Check it against the paper before relying on it.

Integrity signals

Registry

Crossref · 10.3945/jn.112.170233

Cites

18 of 18 references verified0 citation errors · 0 not checkable

Statistics

Nothing to recompute.

Claims the paper makes

0 of 39 cited sources checked · 0 supported · 0 flagged

  • Findingown data

    High statistical heterogeneity was present in the systolic blood pressure meta-analysis (I2 = 66%, Q = 44.3, P < 0.001).

    “We observed a high heterogeneity for systolic (I 2 = 66%, Q = 44.3,P < 0.001) and moderate heterogeneity for diastolic (I 2 = 45%, Q = 25.7,P < 0.01) BP meta-analysis models.”
    Quote in the paperSubstantial claim
  • Findingown data

    In the qualitative synthesis, 12 included studies reported a significant reduction in systolic blood pressure.

    “Twelve studies showed a significant reduction in systolic BP (12,(29)(30)(31)(33)(34)(35)37,38,41,42), whereas a significant change in diastolic BP was observed in 6 studies (10,30,33,(36)(37)(38).”
    Quote in the paperSubstantial claim
  • Findingown data

    Plasma nitrite concentration is not associated with the change in systolic blood pressure.

    “but not with the study duration (P = 0.67) (Fig. 4B) or plasma nitrite concentrations (P = 0.40) (Fig. 4C).”
    Quote in the paperNot a substantial claim
  • Findingown data

    Inorganic nitrate supplementation significantly reduces systolic blood pressure.

    “The effects of beetroot juice supplementation [24.5 mm Hg (95% CI: 26.4,22.5); P < 0.001] (12,(30)(31)(32)(33)(34)(35)(37)(38)(39)(40)(41) and inorganic nitrate [24.2 mm Hg (95% CI: 26.1, 22.2); P < 0.001] (10,33,36,42) on systolic BP were both significant, whereas neither beetroot juice nor inorganic nitrate supplementation was associated with significant changes in diastolic BP (Table 1).”
    Quote in the paperSubstantial claim
  • Findingown data

    Study duration is not associated with the change in diastolic blood pressure.

    “Changes in diastolic BP were not associated with the the daily dose of inorganic nitrate, study duration or plasma nitrite concentrations (Fig. 5).”
    Quote in the paperNot a substantial claim
  • Classified as probably not a substantial claim. 13
  • May combine two claims. 18
  • The quote only partly states this claim. 6

  • Probably not a substantial claim: may not pass S3 (load-bearing).

    Findingown data

    The included trials had 7 to 30 participants per study.

    “The trials were conducted between 2006 and 2012 and included a total of 254 participants, with 7-30 participants per individual study.”
    Quote in the paperNot a substantial claim

  • May combine two claims.

    Findingown data

    In adults, supplementation with inorganic nitrate or beetroot juice reduces systolic blood pressure, with a pooled mean difference of 4.4 mm Hg (95% CI: 5.9, 2.8; P < 0.001).

    “Inorganic nitrate and beetroot juice consumption were associated with greater changes in systolic BP [24.4 mm Hg (95% CI: 25.9, 22.8); P < 0.001] than diastolic BP [21.1 mm Hg (95% CI: 22.2, 0.1); P = 0.06].”
    • Also stated in: § BP quantitative results (meta-analysis). · plain
      “Inorganic nitrate and beetroot juice consumption was associated with greater changes in systolic BP [24.4 mm Hg (95% CI: 25.9, 22.8); P < 0.001] (Fig. 2) than diastolic BP [21.1 mm Hg (95% CI: 22.2, 0.1); P = 0.06] (Fig. 3).”
    Quote in the paperNot a substantial claim

  • Probably not a substantial claim: may not pass S3 (load-bearing).

    Findingown data

    The duration of interventions in the included trials ranged from 2 h to 15 d.

    “The duration of the interventions ranged from 2 h to 15 d and the washout period from 6 to 28 d.”
    Quote in the paperNot a substantial claim

  • Probably not a substantial claim: may not pass S3 (load-bearing).

    Findingown data

    The included trials had a total of 254 participants.

    “The trials were conducted between 2006 and 2012 and included a total of 254 participants, with 7-30 participants per individual study.”
    Quote in the paperNot a substantial claim

  • May combine two claims.

    Findingown data

    The diastolic blood pressure effect was not significant in either short (<3 d) or longer (≥3 d) duration strata.

    “Similarly, the stratification by study duration did not modify the effect on diastolic BP, because the model was not significant for both longer studies [$3 d, 21.7 mm Hg (95% CI: 23.6, 0.1); P = 0.07] (10,30-32,35,37) and shorter [<3 d, 20.2 mm Hg (95% CI: 21.3, 0.9); P = 0.71] interventions (12,33,34,36,39,41,42).”
    Quote in the paperNot a substantial claim

  • May combine two claims.

    Findingreasoning

    The meta-analysis included 16 studies for systolic blood pressure and 13 studies for diastolic blood pressure.

    “Therefore, a meta-analysis of the effects of inorganic nitrate and beetroot supplementation on systolic and diastolic BP was performed for 16 (10,12,(30)(31)(32)(33)(34)(35)(36)(37)(38)(39)(40)(41)(42) and 13 (10,12,(30)(31)(32)(33)(36)(37)(38)(39)(40)(41)(42) studies, respectively.”
    Quote in the paperSubstantial claim

  • Probably not a substantial claim: may not pass S3 (load-bearing).

    Findingown data

    One eligible study was included in the systematic review but excluded from the meta-analysis because full blood pressure results were unavailable.

    “However, this study matched the inclusion and exclusion criteria and it was included in the systematic review (qualitative analysis) but excluded from the meta-analysis (quantitative analysis), because the full results on changes in BP were not available.”
    Quote in the paperNot a substantial claim

  • May combine two claims.

    Findingnone given

    Beetroot juice supplementation has a greater effect on both systolic and diastolic blood pressure than inorganic nitrate supplementation.

    “Beetroot juice supplementation had a greater effect than inorganic nitrate on both systolic and diastolic BP.”
    Quote in the paperNot a substantial claim

  • May combine two claims.

    Findingown data

    In adults, supplementation with inorganic nitrate or beetroot juice does not significantly reduce diastolic blood pressure; the pooled mean difference was 1.1 mm Hg (95% CI: 2.2, 0.1; P = 0.06).

    “Inorganic nitrate and beetroot juice consumption were associated with greater changes in systolic BP [24.4 mm Hg (95% CI: 25.9, 22.8); P < 0.001] than diastolic BP [21.1 mm Hg (95% CI: 22.2, 0.1); P = 0.06].”
    • Also stated in: § BP quantitative results (meta-analysis). · plain
      “Inorganic nitrate and beetroot juice consumption was associated with greater changes in systolic BP [24.4 mm Hg (95% CI: 25.9, 22.8); P < 0.001] (Fig. 2) than diastolic BP [21.1 mm Hg (95% CI: 22.2, 0.1); P = 0.06] (Fig. 3).”
    Quote in the paperSubstantial claim

  • Probably not a substantial claim: may not pass S3 (load-bearing).

    Findingown data

    The included trials were conducted between 2006 and 2012.

    “The trials were conducted between 2006 and 2012 and included a total of 254 participants, with 7-30 participants per individual study.”
    Quote in the paperNot a substantial claim

  • Probably not a substantial claim: may not pass S3 (load-bearing).

    Findingown data

    The washout period in the included trials ranged from 6 to 28 d.

    “The duration of the interventions ranged from 2 h to 15 d and the washout period from 6 to 28 d.”
    Quote in the paperNot a substantial claim

  • May combine two claims.

    Findingown data

    The included studies generally had small samples, short durations, and an over-representation of young, healthy men.

    “However, all studies were characterized by a small sample size and short duration and most of the studies recruited young, healthy, nonsmoking men, making the representativeness of the results debatable.”
    Quote in the paperSubstantial claim

  • May combine two claims.

    Findingown data

    Adding a null mean difference for systolic and diastolic blood pressure reduced the pooled systolic difference by 0.6 mm Hg (from 4.4 to 3.8 mm Hg), while the pooled effect stayed significant (P < 0.001).

    “Similarly, the inclusion of a null mean difference in systolic and diastolic BP [to evaluate the potential effect of the study (29) reporting a nonsignificant effect on BP] reduced the mean difference in systolic BP by 0.6 mm Hg (from 4.4 to 3.8 mm Hg), but the pooled effect size remained significant (P < 0.001) (Supplemental Table 3).”
    Quote in the paperNot a substantial claim0 of 1 sources checked
    • cites [29] Lidder, 2011, Acute effects of dietary nitrate on glucose handling and insulin levels during an oral glucose tolerance test in healthy subjects. Nitric Oxide -., Biol Chem.

      Not checked in the free run.

  • Probably not a substantial claim: may not pass S1 (asserted), S3 (load-bearing), S4 (based).

    Findingnone given

    The combined effect on diastolic blood pressure was a smaller reduction of 1.1 mm Hg.

    “The pooled effect for the 2 interventions showed a reduction in systolic BP of 4.4 mm Hg with a more modest decrease (21.1 mm Hg) in diastolic BP.”
    Quote in the paperNot a substantial claim
    • The authors state this as an assumption: The methodologies of the included studies are consistent enough to combine in a meta-analysis.

  • Probably not a substantial claim: may not pass S3 (load-bearing).

    Findingcitation

    Some included studies enrolled highly physically active individuals because their main aim was to test inorganic nitrate effects on exercise performance.

    “In addition, some of the studies included individuals with high physical activity levels (30)(31)(32)34,35,37), as the primary aim of the studies was to test the effect of inorganic nitrate on exercise performance.”
    Quote in the paperNot a substantial claim0 of 1 sources checked
    • cites (30)(31)(32)34,35,37)

      Not checked in the free run.

  • The quote only partly states this claim.

    Findingown data

    For trials lasting less than 3 days, the pooled diastolic blood pressure change was -0.2 mm Hg (95% CI: -1.3, +0.9; P = 0.71; I2 = 0%).

    “| ,3 d | 7 | 20.2 (21.3, +0.9) | 0.71 | 0 | 2.5 (0.86) |”
    Quote in the paperNot a substantial claim
    • The authors state this as an assumption: The methodologies of the included studies are consistent enough to combine in a meta-analysis.

  • The quote only partly states this claim.

    Findingown data

    For beetroot juice trials, the pooled systolic blood pressure reduction was 4.5 mm Hg (95% CI: -6.4, -2.5; P < 0.001; I2 = 73.7%).

    “| Beetroot juice | 12 | 24.5 (26.4, 22.5) | ,0.001 | 73.7 | 41.4 (,0.001) |”
    Quote in the paperSubstantial claim
    • The authors state this as an assumption: The methodologies of the included studies are consistent enough to combine in a meta-analysis.

  • The quote only partly states this claim.

    Findingown data

    Study duration was not significantly associated with diastolic blood pressure mean difference (slope = -0.002, Q = 0.30, P = 0.58).

    “Meta-regression on the effects of the study duration (in hours) on mean differences in DBP.Slope = 20.002,Q = 0.30, d.f.= 1, P = 0.58.”
    Quote in the paperNot a substantial claim

  • The quote only partly states this claim.

    Findingown data

    Plasma nitrite concentration was not significantly associated with diastolic blood pressure mean difference (slope = -0.002, Q = 0.85, P = 0.35).

    “Meta-regression on the effects of plasma nitrite concentrations (in nmol) on mean differences in DBP.Slope = 20.002,Q = 0.85, d.f.= 1, P = 0.35.”
    Quote in the paperNot a substantial claim

  • The quote only partly states this claim.

    Findingown data

    For beetroot juice trials, the pooled diastolic blood pressure change was -0.9 mm Hg (95% CI: -2.3, +0.5; P = 0.21; I2 = 58.8%).

    “| Beetroot juice | 10 | 20.9 (22.3, +0.5) | 0.21 | 58.8 | 21.6 (0.01) |”
    Quote in the paperNot a substantial claim
    • The authors state this as an assumption: The methodologies of the included studies are consistent enough to combine in a meta-analysis.

  • The quote only partly states this claim.

    Findingown data

    For inorganic nitrate trials, the pooled systolic blood pressure reduction was 4.2 mm Hg (95% CI: -6.1, -2.2; P < 0.001; I2 = 0.5%).

    “| Inorganic nitrate | 4 | 24.2 (26.1, 22.2) | ,0.001 | 0.5 | 2.5 (0.47) |”
    Quote in the paperSubstantial claim
    • The authors state this as an assumption: The methodologies of the included studies are consistent enough to combine in a meta-analysis.

  • May combine two claims.

    Premisecitation

    Inorganic nitrate has high bioavailability and is absorbed quickly from the stomach and upper small intestine.

    “This approach was based on the evidence that inorganic nitrate is rapidly absorbed from the stomach and proximal small intestine with high bioavailability (23).”
    Quote in the paperSubstantial claim0 of 1 sources checked
    • cites [23] Hord, 2011, Dietary nitrates, nitrites, and cardiovascular disease., Curr Atheroscler Rep. source

      Not checked in the free run.

  • May combine two claims.

    Study design and conductown data

    The meta-analysis found no evidence of publication bias for systolic blood pressure; Egger's regression test was nonsignificant (P = 0.47).

    “EggerÕs regression test confirmed the nonsignificant association between the mean differences and the SEs of each study (P = 0.47).”
    Quote in the paperNot a substantial claim

  • Probably not a substantial claim: may not pass S3 (load-bearing).

    Premisecitation

    Recent work proposed that the DASH diet's blood pressure benefits stem from the high nitrate content of certain foods it includes.

    “recent research has suggested that the beneficial effects of the DASH diet on BP are related to the high inorganic nitrate content of some of the food products included in the DASH dietary plan (e.g., green leafy and root vegetables) (9).”
    Quote in the paperNot a substantial claim0 of 1 sources checked
    • cites [9] Hord, 2009, Food sources of nitrates and nitrites: the physiologic context for potential health benefits., Am J Clin Nutr. source

      Not checked in the free run.

  • May combine two claims.

    Study design and conductreasoning

    The meta-analyses relied on retrospective analytical inference and could be affected by factors including study quality, search inclusiveness, assumptions about methodological consistency, inconsistent reporting, limited access to individual data, and inability to identify the exact source of heterogeneity.

    “The meta-analyses are based on retrospective analytical inference, which may be affected by several factors”
    Quote in the paperNot a substantial claim
    • The authors state this as an assumption: The methodologies of the included studies are consistent enough to combine in a meta-analysis.

  • May combine two claims.

    Interpretationreasoning

    Because participants were mostly healthy, normal-weight men, the findings may not generalize to women or to people with cardiovascular or metabolic diseases.

    “Participants recruited in the studies were mostly healthy, normal-weight men and therefore the results may not be applicable to a female population or to individuals with cardiovascular or metabolic diseases.”
    Quote in the paperSubstantial claim

  • Probably not a substantial claim: may not pass S3 (load-bearing). May combine two claims.

    Premisecitation

    Cyclic GMP is the second messenger of the nitric oxide pathway and a biomarker of nitric oxide bioactivity.

    “Cyclic GMP (cGMP) is the second messenger of the NO pathway and it represents a biomarker of NO bioactivity (13).”
    Quote in the paperNot a substantial claim0 of 1 sources checked
    • cites [13] Siervo, 2011, Measurement of in vivo nitric oxide synthesis in humans using stable isotopic methods: a systematic review., Free Radic Biol Med. source

      Not checked in the free run.

  • May combine two claims.

    Interpretationown data

    The intervention periods were short, and whether the blood pressure reductions persist long term is unknown.

    “In addition, the duration of the interventions was short and it is not known whether the observed BP-lowering effects will be maintained in the long term.”
    Quote in the paperSubstantial claim

  • May combine two claims.

    Study design and conductreasoning

    Defining inclusion and exclusion criteria a priori and searching three major electronic databases plus reference lists likely reduced bias and improved representativeness.

    “The clear delineation of a priori inclusion and exclusion criteria and the comprehensive search of 3 major electronic databases and reference lists are likely to have minimized bias and increased the representativeness of the results.”
    Quote in the paperNot a substantial claim

  • Probably not a substantial claim: may not pass S3 (load-bearing).

    Study design and conductnone given

    The authors could not conduct a sensitivity analysis to examine a possible interaction with gender.

    “However, we were unable to perform a sensitivity analysis to assess the interaction with gender, which needs to be tested in future studies.”
    Quote in the paperNot a substantial claim

  • Probably not a substantial claim: may not pass S1 (asserted), S3 (load-bearing), S4 (based). May combine two claims.

    Premisecitation

    A recent meta-analysis found that oral L-arginine supplementation significantly reduced systolic blood pressure by 5.3 mm Hg and diastolic blood pressure by 2.6 mm Hg.

    “A recent meta-analysis of the effects of oral L-arginine supplementation on BP reported a significant effect on systolic BP (25.3 mm Hg) and diastolic BP (22.6 mm Hg) (47), which are comparable with the effect sizes observed in our meta-analysis.”
    Quote in the paperNot a substantial claim0 of 1 sources checked
    • cites [47] Dong, 2011, Effect of oral l-arginine supplementation on blood pressure: a meta-analysis of randomized, double-blind, placebo-controlled trials., Am Heart J. source

      Not checked in the free run.

  • Classified as probably not a substantial claim.

    Interpretationreasoning

    These factors may have changed the pharmacokinetics of plasma nitrate and nitrite and thereby altered their relationship with blood pressure.

    “These factors may have influenced the pharmacokinetic profile of plasma nitrate and nitrite and altered the association with BP.”
    Quote in the paperSubstantial claim

  • May combine two claims.

    Interpretationown data

    The similar blood pressure effects may be explained by comparable daily inorganic nitrate doses, since mean intake was similar between beetroot and nitrate studies (beetroot 12.0 ± 13.2 mmol/dose; inorganic nitrate 15.5 ± 9.2 mmol/dose).

    “The results seem to indicate that the similar effects on BP may be accounted for by comparable daily doses of inorganic nitrate, because the mean intake in the beetroot and nitrate studies was similar (beetroot, 12.0 6 13.2 mmol/dose; inorganic nitrate, 15.5 6 9.2 mmol/dose) and the presence in beetroot juice of other bioactive compounds (vitamin C, magnesium, betaine, and flavonoids) (43)(44)(45)”
    Quote in the paperSubstantial claim

  • May combine two claims.

    Study design and conductown data

    The analysis imputed a pre-post correlation for blood pressure changes, and sensitivity testing showed that the systolic and diastolic models were unaffected by using different correlation values.

    “The analysis was also based on the imputation of prepostintervention correlation of BP changes and the sensitivity analysis confirmed that the models for systolic BP and diastolic BP were not affected by the inclusion of different correlation values.”
    Quote in the paperNot a substantial claim

  • May combine two claims.

    Study design and conductnone given

    All studies reported washout period durations, which were sufficient to reduce carryover effects.

    “All studies reported the duration of washout periods, which was adequate to minimize the influence of carryover effects.”
    Quote in the paperNot a substantial claim
35 of 35

  • The paper relies on this without support.

    Prior to this review, no systematic assessment had been made of randomized trial evidence on inorganic nitrate and beetroot effects on blood pressure.

    “The evidence for the BP-lowering effects of inorganic nitrate and beetroot in randomized clinical trials has not been systematically assessed.”

  • The authors state this as an assumption.

    The methodologies of the included studies are consistent enough to combine in a meta-analysis.

    “assumptions on consistency of methodologies applied across the different studies”
2 of 2

Claims other papers make about this one

Each is checked against this paper’s own text: does it say what the citing paper says it does?

  • This may be due to greater responsiveness resulting from baseline NO deficiency.

    “possibly due to greater responsiveness resulting from baseline NO deficiency [112,155,245].”

    From Dietary Nitrate-Rich Vegetables as Natural Modulators of Health: Mechanisms and Benefits in Ageing Populations (2026) · cites this paper as [155]

    The Introduction links reduced NO bioavailability to hypertension and proposes that dietary nitrate may lower blood pressure by increasing NO availability. It does not say that people with baseline NO deficiency respond more strongly; the discussion reports a nonsignificant association between changes in plasma nitrite and blood-pressure changes. The proposed mechanism is supported, but the claim of greater responsiveness is not. (LLM, conf=0.79)

    Experimental — accuracy not yet measured

  • Older individuals may experience substantial improvements in blood pressure and endothelial function after consuming nitrates.

    “clinical studies suggest that older individuals may experience substantial improvements in blood pressure and endothelial function after consuming nitrates”

    From Dietary Nitrate-Rich Vegetables as Natural Modulators of Health: Mechanisms and Benefits in Ageing Populations (2026) · cites this paper as [155]

    The discussion under FIGURE 3 reports improved resting systolic and diastolic blood pressure after three days of beetroot juice in older healthy participants, but no significant effect on 24-hour blood pressure in older participants with type 2 diabetes. The Introduction links nitric oxide to endothelial function, but the review does not report improved endothelial function after nitrate consumption in older people. The claim therefore extends a blood-pressure finding to an additional outcome and to older individuals more generally. (LLM, conf=0.88)

    Experimental — accuracy not yet measured

  • While the efficacy of dietary nitrate to reduce systemic blood pressure in older age has been extensively studied, relatively few studies have assessed the effects of nitrate supplementation on exercise capacity in healthy older individuals.

    “While the efficacy of dietary NO 3 -to reduce systemic blood pressure in older age has been extensively studied (reviewed in 140; see also 139, 142), relatively few studies have assessed the effects of NO 3 -supplementation on exercise capacity in healthy older individuals.”

    From Dietary Nitrate and Physical Performance (2018) · cites this paper as [140]

    Split into 2 atoms — 1 confirmed, 1 partially supported, 0 disputed, 0 misattributed, 0 unverifiable. Expand the claim to see per-atom verdicts.

    Experimental — accuracy not yet measured

  • Inorganic nitrate found in certain fruit and vegetable juices has the potential to reduce blood pressure.

    “inorganic nitrate found in certain fruit and vegetable juices has shown the potential to reduce blood pressure (Siervo et al. 2013)”

    From Oral nitrate and citrulline decrease blood pressure and increase vascular conductance in young adults: a potential therapy for heart failure (2016) · cites this paper as Siervo et al. 2013

  • Antimicrobial mouthwash abolishes the beneficial blood pressure effect of nitrate supplementation both acutely and chronically.

    “and that antimicrobial mouthwash abolishes this beneficial effect both acutely and chronically (reviewed in:[108,109]).”

    From Enterosalivary nitrate metabolism and the microbiome: Intersection of microbial metabolism, nitric oxide and diet in cardiac and pulmonary vascular health (2017) · cites this paper as [108]

Self-check

Percentages, sums and reported differences re-computed from the paper’s own numbers.

Each contradiction between two passages listed here was confirmed by an independent check.

  • Claimed observed reduction exceeds the pooled systolic effect

    Major

    The conclusion says a systolic reduction of at least 5 mm Hg was observed here, but the paper reports a pooled reduction of 4.4 mm Hg. The claim is used to frame the potential mortality benefit.

  • Study-duration meta-regression has two different P values

    Minor

    The results text gives P = 0.67 for study duration and systolic BP, while the corresponding Figure 4B caption gives P = 0.40.

  • Plasma-nitrite meta-regression has two different P values

    Minor

    The results text gives P = 0.40 for plasma nitrite and systolic BP, while the corresponding Figure 4C caption gives P = 0.87.

  • Diastolic subgroup citations include studies said to lack diastolic data

    Minor

    Studies 34 and 35 are identified as not reporting diastolic BP, yet both appear in citations for the diastolic duration subgroups.

  • Diastolic meta-analysis study count conflicts with subgroup counts

    Minor

    The text says 13 studies contributed to the diastolic meta-analysis, but Table 1 lists seven studies in each of two nonoverlapping duration groups, for a total of 14.

  • Sensitivity analysis reverses the stated diastolic significance result

    Minor

    The main diastolic result is reported as nonsignificant at P = 0.06. The sensitivity analysis says adding a study with a null effect did not modify that result, but reports P < 0.05.

6 of 6

Cites

Flagged first, then by citations

Research works printed but not linked: 28

  1. Ezzati, 2002, Selected major risk factors and global and regional burden of disease., Lancet., 360, 1347, 10.1016/S0140-6736(02)11403-6 · DOI · Paper page
  2. Cutler, 2008, Trends in hypertension prevalence, awareness, treatment, and control rates in united states adults between 1988–1994 and 1999–2004., Hypertension., 52, 818, 10.1161/HYPERTENSIONAHA.108.113357 · DOI
  3. Egan, 2010, US trends in prevalence, awareness, treatment, and control of hypertension, 1988–2008., JAMA., 303, 2043, 10.1001/jama.2010.650 · DOI · Paper page
  4. Savica, 2010, The effect of nutrition on blood pressure., Annu Rev Nutr., 30, 365, 10.1146/annurev-nutr-010510-103954 · DOI
  5. Appel, 2006, Dietary approaches to prevent and treat hypertension: a scientific statement from the American Heart Association., Hypertension., 47, 296, 10.1161/01.HYP.0000202568.01167.B6 · DOI · Paper page
  6. Appel, 1997, A clinical trial of the effects of dietary patterns on blood pressure., N Engl J Med., 336, 1117, 10.1056/NEJM199704173361601 · DOI · Paper page
  7. Moore, 2001, DASH (Dietary Approaches to Stop Hypertension) diet is effective treatment for stage 1 isolated systolic hypertension., Hypertension., 38, 155, 10.1161/01.HYP.38.2.155 · DOI
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Cited by

Sorted by citations

Authors
Siervo, M., Lara, J., Ogbonmwan, I., & Mathers, J. C.
Affiliations
Newcastle University (GB)
Corresponding author
Siervo, Mario
ORCID
Venue
The Journal of Nutrition
Publisher
Elsevier BV
Published
2013-06
Volume
143
Issue
6
Pages
818-826
ISSN
0022-3166 (ISSN-L)
DOI
10.3945/jn.112.170233
OpenAlex
W2142970408
Cited by
375
References
18
Citations by year
2026: 20 · 2025: 24 · 2024: 33 · 2023: 33 · 2022: 18 · 2021: 30 · 2020: 31 · 2019: 31 · 2018: 33 · 2017: 42 · 2016: 34 · 2015: 30 · 2014: 14 · 2013: 2
FWCI
4.52
Type
journal article
Language
en
Open access
Licence
Locations
  • Journal of Nutrition (publishedVersion)
  • PubMed (publishedVersion)
  • Newcastle University ePrints (Newcastle Univesity)
Topics
  • Health Sciences › Medicine › Cardiology and Cardiovascular Medicine › Blood Pressure and Hypertension Studies
  • Health Sciences › Medicine › Physiology › Nitric Oxide and Endothelin Effects
  • Health Sciences › Medicine › Cardiology and Cardiovascular Medicine › Cardiovascular Health and Disease Prevention
Keywords
inorganic nitrate, beetroot juice, blood pressure, systolic blood pressure, nitrate supplementation, dose-response relationship, cardiovascular risk
MeSH terms
Adult, Beverages, Blood Pressure, Female, Humans, Hypertension, Male, Nitrates, Placebos, Randomized Controlled Trials as Topic, MEDLINE, Potassium Compounds, Plant Roots, Cross-Over Studies, Beta vulgaris

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