Hostname: page-component-78c5997874-4rdpn Total loading time: 0 Render date: 2024-11-15T00:32:58.075Z Has data issue: false hasContentIssue false
  • English
  • Français

Effect of inorganic nitrate and beetroot juice supplementation on blood pressure: a systematic review

Published online by Cambridge University Press:  19 October 2012

I. Ogbonmwan ,
M. Siervo ,
J. Lara  and
J. C. Mathers
I. Ogbonmwan
Affiliation:
Human Nutrition Research Centre, Institute for Ageing and Health, Newcastle University, NE4 5PL, UK
M. Siervo
Affiliation:
Human Nutrition Research Centre, Institute for Ageing and Health, Newcastle University, NE4 5PL, UK
J. Lara
Affiliation:
Human Nutrition Research Centre, Institute for Ageing and Health, Newcastle University, NE4 5PL, UK
J. C. Mathers
Affiliation:
Human Nutrition Research Centre, Institute for Ageing and Health, Newcastle University, NE4 5PL, UK
Rights & Permissions [Opens in a new window]

Abstract

An abstract is not available for this content. As you have access to this content, full HTML content is provided on this page. A PDF of this content is also available in through the ‘Save PDF’ action button.
Type
Abstract
Information
Proceedings of the Nutrition Society , Volume 71 , Issue OCE2: Summer Meeting hosted by the Irish Section, 16–19 July 2012, Translational nutrition: integrating research, practice and policy , 2012 , E33
Copyright
Copyright © The Authors 2012

Inorganic nitrate and beetroot juice supplementation have both been associated with a decrease in blood pressure in humans( Reference Gilchrist 1 ). The effects seem to be mediated by an increased non-enzymatic conversion of nitrate into nitric oxide, a key endothelial-derived vasodilator( Reference Lundberg 2 ).

The aim of the study was to perform a systematic review of randomized clinical trials to evaluate the effects of inorganic nitrate and beetroot supplementation on systolic (SBP) and diastolic (DBP) blood pressure in humans.

We searched the Embase, Medline and Scopus medical databases from inception until March 2012. The databases were searched for title and abstract and were restricted to human, randomized, placebo controlled clinical trials published in English. Predefined search terms (nitrate, blood pressure, hypertension, vascular, nitrate, nitric oxide, beet root) and Boolean operators (AND, OR, “”, *) were used to increase the power of the search strategy. The protocol for the study has been registered with PROSPERO International prospective register of systematic reviews (CRD42012002144). We identified 8284 records and 3135 articles were included in the database after removal of duplicates. Titles and abstracts of each article were independently evaluated for eligibility by two members of the research team (IO, MS) and discrepancies were resolved by discussion with a third reviewer (JL). Twenty-two articles were selected and the full text of each manuscript was obtained for data extraction. The reference lists of the selected articles and relevant reviews were searched to retrieve other potential eligible articles. Eight articles were excluded after data extraction and 14 studies were included in the database for the final analysis (Table 1).

Table 1. Effects of beetroot and inorganic nitrate supplementation on systolic (SBP) and diastolic (DBP) blood pressure in randomized clinical trials

↓=Significant decrease in BP; −=No significant change in BP; n/a=BP values were not available; *=results reported in the same article.

All studies were characterized by a crossover, double-blind, placebo controlled, randomized study design. Thirteen studies included healthy volunteers and one study was conducted in patients with type 2 diabetes. Large heterogeneity was observed in the duration of the interventions (range: 3 hours – 15 days) but it was not associated with changes in SBP and DBP. An improvement in SBP was observed in 11 studies whereas only 5 studies reported a decrease in DBP. Beetroot juice supplementation did not have an effect on BP in type 2 diabetic patients.

Inorganic nitrate and beetroot juice supplementation are both associated with beneficial effects on vascular homeostasis, which could be mechanistically explained by an increased generation of nitric oxide. The majority of the studies have been conducted in healthy individuals and therefore the benefits of inorganic nitrate and beetroot supplementation in subjects at high risk of cardiovascular diseases remain to be established.

References

1. Gilchrist, M et al. (2011) Cardiovasc Res 89(3): 492–498.CrossRefGoogle Scholar
2. Lundberg, J et al. (2008) Nat Rev Drug Discov 7(2): 156–167.Google Scholar
3. Webb, A et al. (2008) Hypertension 51(3): 784–790.CrossRefGoogle Scholar
4. Bailey, S et al. (2009) J Appl Physiol 107(4): 1144–1155.CrossRefGoogle Scholar
5. Bailey, S et al. (2010) J Appl Physiol 109(1): 135–148.Google Scholar
6. Kapil, V et al. (2010) Hypertension 56(2): 274–281.CrossRefGoogle Scholar
7. Vanhatalo, A et al. (2010) Am J Physiol 299(4): R1121–31.Google Scholar
8. Gilchrist, M et al. (2011) J Hum Hyper 25(10): 626.Google Scholar
9. Lansely, K et al. (2011) Med Sci Sports Exerc 43(6): 1125–31.Google Scholar
10. Lansely, K et al. (2011) J Appl Physiol 110(3): 591–600.CrossRefGoogle Scholar
11. Larsen, F et al. (2006) N Engl J Med 355(26): 2792–2793.Google Scholar
12. Larsen, F et al. (2007) Acta Physiol (Oxf) 191(1): 59–66.CrossRefGoogle Scholar
13. Larsen, F et al. (2010) Free Radic Biol Med 48(2): 342–347.Google Scholar
14. Lidder, S, et al. (2011) Nitr Ox – Biol & Chem 24: S32.Google Scholar
15. Bahra, M et al. (2012) Nitr Ox Article In Press.Google Scholar
16. Cermak, N et al. (2012) Int J Spt Nut & Ex Met 22(1): 64–72.Google Scholar
Figure 0

Table 1. Effects of beetroot and inorganic nitrate supplementation on systolic (SBP) and diastolic (DBP) blood pressure in randomized clinical trials