Beetroot Scientific References and Clinical Study Library

Beetroot is one of the most studied vegetables in nutrition science, yet claims about it often travel faster than the evidence. This page collects beetroot scientific references in one place, so you can see which papers exist, what design each used, and how far each result can be trusted. Use it to check a statement, find an original paper, or judge how strong the proof really is before you rely on a headline.

1. How This Beetroot Scientific References Library Is Organized

Evidence is not equal. A single small trial and a pooled analysis of many trials carry different weight, so this library is sorted by study type, from the strongest summaries down to early laboratory work.

• Order of use: systematic reviews and meta-analyses first, then randomized trials, observational work, pharmacokinetics, safety, mechanisms and preclinical studies.
• What counts: peer-reviewed papers indexed in PubMed, plus one regulatory opinion. Press releases, blogs and brand pages are excluded.
• Citation style: numbers in square brackets, such as [7], point to the reference list in section 11.
• Honest limits: most trials use beetroot juice, not capsules or powders. Many are small and short. Nitrate is the best-studied active component, so a lot of the data is really about dietary nitrate.

No study here shows that beetroot treats or cures any disease. Where a result is modest or mixed, this page says so.

2. Systematic Reviews on Beetroot Nitrate Evidence

Systematic reviews search for all relevant studies using a stated method, then appraise them. They give the best overview of beetroot nitrate evidence.

• Clifford and colleagues reviewed red beetroot for health and disease. They covered blood pressure, exercise performance and other outcomes, and noted that the quality of trials varied [11].
• Lundberg and colleagues described the nitrate-nitrite-nitric oxide pathway and its therapeutic potential. This is a narrative review that frames why nitrate-rich foods like beetroot are studied at all [12].
• A 2018 systematic review on beetroot juice and hypertension is also listed in the reference library [21].

Reader takeaway: reviews agree that beetroot is promising for blood pressure and exercise, and that larger, longer trials are still needed.

3. Meta-Analyses

Meta-analyses pool numerical results from several trials to estimate an average effect.

• Blood pressure: Siervo et al. pooled 16 trials of inorganic nitrate and beetroot juice in adults. They reported an average drop of roughly 4 mmHg in systolic and about 1 mmHg in diastolic pressure [9]. Effects were larger with higher nitrate doses and in short studies.
• Endurance exercise: McMahon et al. pooled trials in healthy adults. Beetroot or nitrate supplements gave small improvements in some time-trial and time-to-exhaustion tests, with wide variation between studies [10].

Pooled effects are small to moderate, and the trials behind them are often short, so long-term benefit is not established.

4. Randomized Controlled Trials: Beetroot Clinical Studies

Randomized controlled trials (RCTs) are the core of beetroot clinical studies, because random assignment limits bias.

Blood pressure and vascular health

• Webb et al. gave healthy adults 500 mL of beetroot juice. Blood pressure fell within hours, with a peak effect around three to four hours [1].
• Hobbs et al. tested juice in healthy men and found a measurable blood pressure reduction [4].
• Kapil et al. ran a double-blind, placebo-controlled trial in hypertensive adults. Daily beetroot juice for four weeks lowered clinic and home blood pressure [7].
• Gilchrist et al. studied adults with type 2 diabetes. Blood pressure and insulin sensitivity were not clearly improved after two weeks of juice [6].

Exercise performance

• Larsen et al. showed that dietary nitrate (given as sodium nitrate, not beetroot) lowered the oxygen cost of cycling [2].
• Bailey et al. reported that six days of beetroot juice reduced oxygen cost and improved time to exhaustion in healthy men [3].
• Murphy et al. found that eating whole baked beetroot before a 5-km run was linked to faster times in recreational runners [5].

Most trials are crossover designs with small groups, which limits how widely results apply.

5. Observational Human Studies

Observational studies follow people over time or compare groups without assigning a treatment. They can show links, not cause and effect.

Few cohort studies isolate beetroot specifically. Most work looks at overall nitrate-rich vegetable intake, where beetroot is only one source. Hord and colleagues analyzed which foods supply nitrate and nitrite in the diet, which is the starting point for that research [15]. For readers who want observational papers, this PubMed query is a reliable start: (beetroot OR "beet") AND (cohort OR "cross-sectional").

Because beetroot-specific observational data is thin, this library does not rely on it for any health claim.

6. Pharmacokinetic Studies

Pharmacokinetic studies track how a compound is absorbed, converted and cleared.

• Webb et al. measured plasma nitrite after beetroot juice. Nitrite rose within hours and tracked the blood pressure effect [1].
• Wylie et al. compared three doses of concentrated juice (about 4.2, 8.4 and 16.8 mmol nitrate). Plasma nitrate and nitrite rose in a dose-dependent way, and a higher dose did not always improve performance more [8].
• Govoni et al. showed that using an antibacterial mouthwash sharply reduced the plasma nitrite rise after a nitrate dose [14].

The mouthwash result matters in practice: conversion of nitrate to nitrite depends on bacteria in the mouth.

7. Safety and Toxicology Studies

• Nitrate intake: the European Food Safety Authority reviewed nitrate in vegetables and concluded that the health benefits of vegetable intake outweigh the risks from their natural nitrate [16]. Hord et al. discuss how dietary nitrate differs from nitrate in processed meats [15].
• Oxalate: beetroot is a notable source of oxalate. Noonan and Savage summarize oxalate content in foods and why people prone to kidney stones may need to limit high-oxalate foods [17].
• Beeturia: pink or red urine after eating beetroot is common and harmless in most people.
• Medication: people taking blood pressure medicines, or those with kidney disease, should ask a clinician before using concentrated beetroot products.

8. Mechanistic Studies

These studies explain how an effect might happen.

• Dietary nitrate is reduced to nitrite by oral bacteria, then to nitric oxide, which relaxes blood vessels [12][13].
• Larsen et al. found that dietary nitrate lowered the oxygen cost of exercise and improved mitochondrial efficiency in humans [20].
• Beetroot also contains betalains, pigments studied for antioxidant behavior [18].

Mechanisms show plausibility. They do not prove a benefit in real people.

9. Preclinical Studies

Preclinical work uses cells or animals. It generates ideas but cannot be applied directly to humans.

• Kanner et al. described betalains as dietary antioxidants in laboratory systems [18].
• Reddy et al. compared natural food colors, including beetroot-derived pigments, for effects on lipid peroxidation and tumor cell growth in vitro [19].

No laboratory finding on this page should be read as a human treatment claim.

10. Study Table: Year, Design, Population and Dose

Doses are summarized from the original papers. Please confirm exact values in the source before quoting them.

11. DOI, PubMed and Official Links for the Beetroot Research Library

Add the DOI after https://doi.org/. For papers without a DOI listed, search the exact title in PubMed.

1. Webb AJ et al. Hypertension 2008;51:784-790. DOI: 10.1161/HYPERTENSIONAHA.107.103523
2. Larsen FJ et al. Acta Physiol (Oxf) 2007;191:59-66. DOI: 10.1111/j.1748-1716.2007.01713.x
3. Bailey SJ et al. J Appl Physiol 2009;107:1144-1155. DOI: 10.1152/japplphysiol.00722.2009
4. Hobbs DA et al. Br J Nutr 2012;108:2066-2074. DOI: 10.1017/S0007114512000190
5. Murphy M et al. J Acad Nutr Diet 2012;112:548-552. DOI: 10.1016/j.jand.2011.11.009
6. Gilchrist M et al. Free Radic Biol Med 2013;60:89-97. DOI: 10.1016/j.freeradbiomed.2013.01.024
7. Kapil V et al. Hypertension 2015;65:320-327. DOI: 10.1161/HYPERTENSIONAHA.114.04675
8. Wylie LJ et al. J Appl Physiol 2013;115:325-336. DOI: 10.1152/japplphysiol.00372.2013
9. Siervo M et al. J Nutr 2013;143:818-826. DOI: 10.3945/jn.112.170233
10. McMahon NF et al. Sports Med 2017;47:735-756. DOI: 10.1007/s40279-016-0617-7
11. Clifford T et al. Nutrients 2015;7:2801-2822. DOI: 10.3390/nu7042801
12. Lundberg JO et al. Nat Rev Drug Discov 2008;7:156-167. DOI: 10.1038/nrd2466
13. Kapil V et al. Physiological role for nitrate-reducing oral bacteria in blood pressure control. Free Radic Biol Med 2013;55:93-100. (PubMed title search)
14. Govoni M et al. Nitric Oxide 2008;19:333-337. DOI: 10.1016/j.niox.2008.08.003
15. Hord NG et al. Am J Clin Nutr 2009;90:1-10. DOI: 10.3945/ajcn.2008.27131
16. EFSA Panel on Contaminants in the Food Chain. Nitrate in vegetables. EFSA Journal 2008;689. DOI: 10.2903/j.efsa.2008.689
17. Noonan SC, Savage GP. Oxalate content of foods and its effect on humans. Asia Pac J Clin Nutr 1999;8:64-74. (PubMed title search)
18. Kanner J et al. J Agric Food Chem 2001;49:5178-5185. DOI: 10.1021/jf010456f
19. Reddy MK et al. J Agric Food Chem 2005;53:9268-9273. DOI: 10.1021/jf051399j
20. Larsen FJ et al. Cell Metab 2011;13:149-159. DOI: 10.1016/j.cmet.2011.01.004
21. Bonilla Ocampo DA et al. Dietary nitrate from beetroot juice for hypertension: a systematic review. Biomolecules 2018;8:134. (PubMed title search)

Official and database links: PubMed (pubmed.ncbi.nlm.nih.gov), Cochrane Library (cochranelibrary.com), ClinicalTrials.gov, and EFSA (efsa.europa.eu).

Use the Evidence Wisely

Use this library as a map, not a verdict. Read the original papers, note the dose and population, and talk to a doctor or registered dietitian before using beetroot products if you take blood pressure medicine, have kidney stones or kidney disease, or are pregnant.