Research dossier
Clinical research on Beetroot
12 trials reviewed across 2 indications.
Strongest evidence
Exercise economy & endurance performance
Mechanism
Nitrate-derived nitric oxide may influence muscle contractile efficiency, oxygen delivery and the energy cost of force production. These mechanisms can help explain findings in some exercise tests, but do not establish a performance benefit on their own.
Reviews suggest small, outcome-specific benefits for exercise tolerance, muscular endurance and some power measures. Time-trial findings are less consistent, despite positive small trials. Newer evidence also supports some sprint outcomes; no universal 8 mmol cutoff is established.
Training status, exercise task and dosing protocol may affect results, but elite athletes are not uniformly nonresponders. Most reviews in the 2025 umbrella review had low or critically low methodological quality.
Trials cited
Dietary nitrate and oxygen cost of exercise
positive · RCT
Larsen et al., 2007, Acta Physiologica (Oxf)n=9Three days of sodium nitrate reduced submaximal cycling oxygen cost: VO2 fell from 2.98 to 2.82 L/min (p<0.02), while gross efficiency rose from 19.7% to 21.1% (p<0.01). Lactate did not change.
Tiny sample (n=9), used pharmaceutical sodium nitrate rather than beetroot, and measured physiology — not race performance. Mechanistically seminal, but a long way from a real-world outcome.
Beetroot juice reduces O2 cost of walking and running
positive · RCT
Lansley et al., 2011, Journal of Applied Physiologyn=9Compared with nitrate-depleted juice, nitrate-rich juice reduced the oxygen cost of walking and running and extended time to task failure during severe-intensity running. The matched placebo supports a role for nitrate in these effects.
Small (n=9), short-term study of men. Laboratory economy and exercise-tolerance findings do not establish a comparable improvement in race times.
Beetroot juice improves cycling time-trial performance
positive · RCT
Lansley et al., 2011, Medicine & Science in Sports & Exercisen=9A single dose of nitrate-rich juice improved 4-km time-trial performance by ~2.8% and 16.1-km by ~2.7% versus nitrate-depleted placebo in nine cyclists, with higher power output for similar oxygen uptake.
Small (n=9), single acute dose in club-level cyclists. The 2025 umbrella review did not find a significant pooled time-trial benefit, so this result should not be generalized to all athletes or events.
Beetroot juice dose-response for plasma nitrite and exercise
positive · RCT
Wylie et al., 2013, Journal of Applied Physiologyn=10In 10 men, 8.4 and 16.8 mmol nitrate extended time to task failure by 14% and 12%; 4.2 mmol did not. Oxygen cost fell significantly at 16.8 mmol, while the reduction at 8.4 mmol did not reach significance (p=0.06).
This small acute study found no extra exercise-tolerance benefit at 16.8 versus 8.4 mmol. It does not establish a universal 8 mmol minimum or a ceiling for every outcome, population or dosing schedule.
Beetroot juice and repeated-sprint performance across training levels
mixed · RCT
Jonvik et al., 2018, European Journal of Sport Sciencen=52Six days of nitrate-rich juice did not improve peak or mean Wingate power, but shortened time to peak power by ~2.8%. Responses did not differ between recreational, competitive and elite athletes.
One sprint protocol in 52 athletes. Null peak/mean-power findings coexist with faster time to peak power and cannot support a blanket claim that nitrate has no sprint benefits.
Dietary nitrate and exercise performance (umbrella review)
mixed · Systematic review
Poon et al., 2025, Sports Medicinen=2672Small benefits were found for time to exhaustion, distance covered, muscular endurance and peak power, plus faster time to peak power. Other outcomes, including time-trial performance, did not improve significantly in pooled analyses.
Most included reviews were rated low or critically low quality. Subgroup findings do not establish a universal minimum effective dose; overlapping evidence should not be counted as independent trials.
Beetroot juice and aerobic/anaerobic performance (meta-analysis)
positive · Meta-analysis
Cai et al., 2026, Frontiers in Nutritionn=519Across 33 studies, pooled effects favored beetroot juice for high-intensity interval sprint performance, mean power output and VO2max. Findings support some sprint/power benefits rather than a blanket null effect.
Small-to-moderate effects across varied methods. Subgroup differences were not significant and are exploratory. Differences from earlier reviews underscore that results depend on the evidence set and outcome.
Blood pressure & vascular function
Mechanism
Dietary nitrate is concentrated in saliva, where nitrate-reducing oral bacteria convert it to nitrite. Swallowed nitrite is reduced further to nitric oxide in the acidic, low-oxygen environment of the stomach and tissues. Nitric oxide relaxes vascular smooth muscle and lowers blood pressure — bypassing the body's own nitric-oxide-synthase pathway entirely.
Low-certainty evidence: a 2024 meta-analysis of 11 trials found a 5.31 mmHg reduction in office systolic BP in adults with hypertension, but no significant office diastolic or 24-hour BP benefit. Individual trials are inconsistent.
These pooled findings concern adults with hypertension, not everyone taking beetroot. Responses vary, including among people taking BP medication. Beetroot is not a substitute for prescribed medication.
Inorganic nitrate / beetroot juice and blood pressure (meta-analysis)
positive · Meta-analysis
Siervo et al., 2013, Journal of Nutritionn=254Across 16 RCTs (254 participants), systolic BP fell by 4.4 mmHg (95% CI -5.9 to -2.8). The diastolic reduction was not significant. Meta-regression associated higher nitrate doses with larger systolic reductions, but cannot establish causation.
Small crossover trials lasting 2 hours to 15 days. These short-term BP findings do not establish prevention of cardiovascular events; newer hypertension-specific evidence is low certainty.
Dietary nitrate for sustained BP lowering in hypertension
positive · RCT
Kapil et al., 2015, Hypertensionn=68In 68 adults with hypertension, four weeks of daily nitrate-rich juice reduced office systolic BP by 7.7 mmHg versus placebo, with reductions in home and ambulatory BP and improved endothelial function.
Four weeks is short, and the endpoint was BP rather than cardiovascular events. Later pooled evidence did not find significant 24-hour BP benefits, so this trial should not be read as a universal response.
Beetroot juice over 4 weeks in older hypertensives (null)
Null · RCT
Fejes et al., 2024, Food & Functionn=15Despite higher plasma and salivary nitrate/nitrite, four weeks of nitrate-rich juice did not improve forearm vascular function, 24-hour ambulatory BP or home BP versus placebo in 15 older adults with hypertension taking medication.
Small (n=15). But it sits alongside other null trials in treated hypertensives, tempering the optimistic read from Kapil 2015 — the population and medication background matter.
Beetroot juice and blood pressure in hypertension (meta-analysis)
mixed · Meta-analysis
Grönroos et al., 2024, Nutrition, Metabolism and Cardiovascular Diseasesn=349Across 11 trials (349 patients), office systolic BP fell by 5.31 mmHg (95% CI -7.46 to -3.16). There was no significant effect on office diastolic BP or 24-hour BP outcomes.
Low-certainty evidence with moderate-to-high heterogeneity. The studied dose range is not an established optimal dose, and these results do not establish prevention of cardiovascular events.
2 forms of Beetroot compared
Beet It Sport (and similar)
Nitrate-standardized beetroot juice / shot
Declared nitrate content allows dose comparison; batch testing provides stronger assurance than a juice or shot label alone
Best forBlood pressure, exercise economy and enduranceCompare milligrams of nitrate per serving, not milligrams of beetroot or milliliters of juice. Exercise studies use varied doses, often timed 2–3 hours before exercise; the 2025 umbrella review found greater time-to-exhaustion effects in subgroups using ≥6 mmol/day (372 mg nitrate/day) and >3 days, not a universal cutoff. The 2024 hypertension review studied 200–800 mg nitrate/day, with low-certainty BP evidence. These are nitrate amounts, not beetroot-mass dosing recommendations.
Plain beetroot powder
Nitrate dose is unknown from powder mass alone; content varies by product and batch
Best forBlood pressure or exercise claims require a known nitrate dose to compare with trialsA 500 mg beetroot capsule is not 500 mg nitrate. Do not assume a fixed nitrate percentage for plain powder. An assay of 24 products across 45 lots found nearly 50-fold variation in nitrate per serving across powders and drinks, with variation within products too. A powder or capsule with quantified nitrate can be assessed on that amount; an unstandardized product has an unknown nitrate dose, not demonstrated zero efficacy.
Are you deficient? Symptoms, risk groups, lab tests
Beetroot is a food, not an essential nutrient — there is no 'beetroot deficiency.' It is supplemented for the pharmacological effect of its dietary nitrate on nitric oxide, not to correct a shortfall. Leafy greens (rocket, spinach) and beets are the richest dietary nitrate sources.
Side effects and drug interactions
Side effects
Beeturia (red/pink urine and stool)
Common
Harmless reddish discoloration of urine and stool from betalain pigments, seen in roughly 10–14% of people. Frequently mistaken for blood. Benign and reversible — but worth knowing before it causes a panic.
Worse with:nitrate-standardized beetroot juice, beetroot powder
GI upset
Uncommon
Mild stomach discomfort or loose stool, mostly from the sugar and fiber load of concentrated juice rather than the nitrate itself.
Lightheadedness / hypotension
Uncommon
Because nitrate lowers blood pressure via nitric oxide, large doses can cause mild lightheadedness, especially when stacked with blood-pressure medication or nitrates.
Drug interactions
Additive effect
nitrates (nitroglycerin, isosorbide)PDE-5 inhibitors (sildenafil, tadalafil)antihypertensivesDietary nitrate raises nitric oxide and is vasodilatory. Stacking with prescription nitrates, ED drugs, or blood-pressure medication can produce additive blood-pressure lowering.
Use caution combining concentrated beetroot/nitrate with prescription nitrates, PDE-5 inhibitors, or antihypertensives; watch for lightheadedness. Discuss with a prescriber if you are on nitrate therapy for angina.
Reduces nutrient status
antibacterial / antiseptic mouthwash (chlorhexidine, cetylpyridinium)Some antibacterial mouthwashes suppress nitrate-reducing oral bacteria and can reduce conversion of dietary nitrate to nitrite. This may blunt nitrate-related effects, but does not establish that every mouthwash abolishes every benefit.
Do not stop prescribed mouthwash to improve a supplement response. Ask your dentist or prescriber about mouthwash use if you are considering nitrate supplementation.
Other critical caveats
- Dose comparisons must use nitrate, not total beetroot mass. Nitrate content varies widely among products and batches. A powder, capsule or juice without quantified nitrate has an unknown nitrate dose; a fixed powder-to-nitrate conversion is not justified.
- Antibacterial mouthwash can reduce oral nitrate-to-nitrite conversion (Govoni 2008). This biomarker effect is not evidence that every BP or exercise benefit is abolished. Do not discontinue prescribed mouthwash without advice from your dentist or prescriber.
- Exercise benefits are small and outcome-specific. Poon 2025 found benefits in some endurance and power measures, and Cai 2026 supports some sprint outcomes. Wylie 2013 does not establish a universal 8 mmol cutoff; more nitrate is not necessarily more effective.
- Blood-pressure evidence is low certainty. Grönroos 2024 found lower office systolic BP, but no significant office diastolic or 24-hour BP benefit. The 200–800 mg/day studied range refers to nitrate, not beetroot, and does not establish an optimal dose or replace prescribed medication.
- Red urine and stool (beeturia) is benign. It affects ~10–14% of people and is harmless betalain pigment, not blood — but it surprises people who don't expect it.
Frequently asked
Does beetroot actually lower blood pressure?
It may lower office systolic blood pressure in adults with hypertension. A 2024 meta-analysis of 11 trials found an average reduction of 5.31 mmHg, but no significant office diastolic or 24-hour BP benefit. Evidence was low certainty and individual results varied. The studies used 200–800 mg nitrate/day, not that amount of beetroot powder. Do not replace prescribed BP medication with beetroot.Is beetroot powder as good as beetroot juice?
The key comparison is nitrate per serving, not powder versus juice. Nitrate content varies widely across products and batches; there is no reliable universal percentage for plain powder. Look for declared nitrate content and preferably batch testing. A powder or capsule with quantified nitrate can be compared with trial doses. Without that information, its nitrate dose is unknown — not automatically ineffective.Can mouthwash reduce beetroot's effects?
Some antibacterial mouthwashes suppress the oral bacteria that convert nitrate to nitrite. A small chlorhexidine study found a reduced rise in plasma nitrite after nitrate intake, but did not test BP or exercise benefits. The effect depends on the mouthwash and context; it does not mean every benefit is abolished. Do not stop prescribed mouthwash without advice from your dentist or prescriber.Will beetroot make me faster or fitter?
Possibly, but the average benefits are small and depend on the task. Reviews support some exercise-tolerance, muscular-endurance and power outcomes, while race-time results are less consistent. Some sprint outcomes also improve. Studies often time intake 2–3 hours before exercise; a 2025 umbrella review found greater time-to-exhaustion effects in ≥6 mmol/day (372 mg nitrate/day) and >3-day subgroups. These are not universal minimums, and beetroot mass alone cannot establish the nitrate dose.Why is my urine red after taking beetroot?
That's beeturia — harmless red or pink discoloration of urine (and sometimes stool) from beetroot's betalain pigments. It happens to roughly 10–14% of people and is completely benign, though it's often mistaken for blood. It's not a sign anything is wrong.
References
- 01Examine.com — Nitrate
- 02Siervo et al., 2013 — Inorganic nitrate and beetroot juice and blood pressure meta-analysis (J Nutr)
- 03Kapil et al., 2015 — Dietary nitrate provides sustained BP lowering in hypertension (Hypertension)
- 04Wylie et al., 2013 — Beetroot juice dose-response (J Appl Physiol)
- 05Govoni et al., 2008 — Antibacterial mouthwash attenuates plasma nitrite rise (Nitric Oxide)
- 06Grönroos et al., 2024 — Beetroot juice and blood pressure in hypertension (systematic review and meta-analysis)
- 07Poon et al., 2025 — Dietary nitrate and exercise performance (umbrella review of 20 reviews)
- 08Cai et al., 2026 — Beetroot juice and aerobic/anaerobic performance (systematic review and meta-analysis)
- 09Gallardo and Coggan — Nitrate and nitrite content of beet juice products marketed to athletes
Last reviewed2026-10-21