Beetroot Juice

Last reviewed October 2026 · Based on 37 studies

Bottom line

Beetroot juice may give healthy adults a small gain in tests of endurance to exhaustion. It has not reliably improved time trials, and sprint results conflict. In adults with high blood pressure, reviews of small trials find clinic systolic pressure falls by about 4 to 5 mmHg, but 24-hour results are mixed. The harms have been studied less than the benefits.

What it helps with

Extends time to exhaustion in endurance exercise — Benefit, evidence grade C (Limited). Several meta-analyses agree on small to moderate gains; downgraded for inconsistency (time-trial and well-trained-athlete results are null) and for low-quality included reviews in the umbrella review.
Improves time-trial performance — No effect, evidence grade B (Moderate). Three reviews report no significant time-trial effect; downgraded once because a 2020 review finds a small overall benefit across all tests, so results are not fully consistent.
Improves sprint and high-intensity interval performance — Mixed results, evidence grade C (Limited). One 2021 meta-analysis of 17 studies found no significant gain and a 2026 review of 33 studies found gains; the results conflict and the 2026 subgroup findings are hypothesis-generating.
Adds to gains from endurance training — No effect, evidence grade C (Limited). Nine studies with 228 people; downgraded for small total sample, and the review reports low statistical power.
Lowers blood pressure — Mixed results, evidence grade C (Limited). Meta-analyses of small trials mostly find a clinic systolic drop of 4 to 5 mmHg, but 24-hour results and some meta-analyses are null; downgraded for inconsistency and small total samples, plus low-certainty evidence in the largest review.
Improves exercise capacity in heart, lung and metabolic disease — No effect, evidence grade C (Limited). Small crossover trials in patients with low statistical power; downgraded for small total sample and inconsistent subgroup results.

What it is

Beetroot juice is a drink rich in inorganic nitrate, which the body can convert into nitric oxide [1]. It is the most commonly used route of dietary nitrate supplementation [2]. Juice brand is one of several factors that may change the effect, according to a 2026 review [3].

How it might work

Proposed mechanism: nitric oxide relaxes blood vessels, which may increase oxygen and nutrient delivery to muscles and improve muscle efficiency [1]. A 2017 meta-analysis suggests some blood pressure effects may not depend on nitrate, so the mechanism is not fully understood [4].

What the research says

Endurance: a 2017 meta-analysis of 76 trials in healthy adults found a significant gain in time to exhaustion, with an effect size of 0.33 [5]. An umbrella review of 20 systematic reviews found the same for time to exhaustion, with a standardised mean difference of 0.33 [6]. Time trials: a 2021 meta-analysis found no significant difference in time-trial performance [7], and a 2018 review found no significant effect on time to cover a set distance [8]. Sprints and intervals: a 2021 meta-analysis of 17 studies found no significant change in power output [9], while a 2026 review of 33 studies found significant gains in high-intensity sprint performance and mean power output [3]. Training: adding nitrate to at least three weeks of training did not significantly improve VO2peak or time to exhaustion in nine studies with 228 people [10]. Heart, lung and metabolic disease: a 2024 meta-analysis of 22 crossover trials found no significant effect on time to exhaustion, oxygen uptake or six-minute walk distance [11]. In COPD, a 2021 meta-analysis of eight trials found no significant change in six-minute walk distance, cycling endurance time or maximal oxygen uptake [12]. Blood pressure: in adults with hypertension, clinic systolic pressure fell by about 5.3 mmHg versus placebo in a 2024 meta-analysis of 11 trials, with low certainty [13], and by 4.95 mmHg in a 2022 meta-analysis of 7 trials [14]. A 2017 meta-analysis of 22 trials found systolic pressure 3.55 mmHg and diastolic pressure 1.32 mmHg lower, with larger drops at higher juice doses and longer use [4]. Individual trials reported bigger reductions: a 4-week trial in 68 adults found drops of about 8 mmHg in clinic, 24-hour and home readings [15], a 7-day crossover trial in 20 treated adults found a 24-hour systolic drop of 8 mmHg [16], and a 60-day trial in 47 Tanzanian adults found a 24-hour systolic drop of 10.8 mmHg versus 0.3 mmHg with placebo [17]. Other results are mixed: a 2017 meta-analysis found the systolic drop only in clinic readings, not with 24-hour or home monitoring [18], a 2023 meta-analysis found no significant drop in people with hypertension [19], and a 2026 meta-analysis of sodium nitrate in older adults found no significant drop [20]. A 2026 cohort linked higher plant-sourced nitrate intake to a 3.5 mmHg greater 5-year fall in systolic pressure [21].

Doses used in studies

In an umbrella review of endurance studies, time-to-exhaustion gains were larger with at least 6 mmol of nitrate a day (about 372 mg) and more than three days of use [6]. The same umbrella review of 15 meta-analyses reported significant gains with a single dose 2 to 3 hours before exercise, and with 8.3 to 16.4 mmol (515 to 1,017 mg) a day, but described most effects as small or negligible [2]. In hypertensive adults, trials used 70 to 250 mL of juice a day, about 200 to 800 mg of nitrate, for 3 to 60 days [14][13]. A 2017 meta-analysis of blood pressure found larger drops with 500 mL a day of juice than with 70 to 140 mL a day [4].

Safety and interactions

Upper limit: none was found in the studies read. A 2021 review warns that drinking beetroot juice can easily push nitrate intake above the acceptable daily intake, which stimulates formation of N-nitroso compounds, known to be carcinogenic [1]. Side effects: the same review says data on negative effects are rather limited compared with data on benefits [1]. The studies read did not give a full list of common side effects. Medicine interactions: because beetroot juice can lower blood pressure in some trials, people on blood pressure medicines should talk to a doctor before using it regularly [13]. Interactions with other medicines were not covered by the studies read. Pregnancy and breastfeeding: small trials have tested beetroot juice only in pregnant women with high blood pressure or kidney disease [22][23]. An 8-day feasibility trial in 40 women with high blood pressure found the juice acceptable but no overall blood pressure reduction [22]. In a 2026 trial in 108 women with chronic kidney disease, those given 400 mg of nitrate a day had fewer serious adverse events than standard care (23% vs 51%) and fewer needed blood pressure medicines (37% vs 66%), but the trial tested recruitment, not efficacy [23]. Safety in healthy pregnancy and in breastfeeding is not established. Kidney disease: people with kidney disease should check with their doctor first [23].

Caveats and open questions

Results conflict across tests and reviews, including sprints [9][3] and blood pressure [13][19][20]. Blood pressure drops are seen more often in clinic readings than with 24-hour monitoring [18]. Many trials have low statistical power [10]. Most reviews are of low methodological quality [6]. Subgroup differences, such as by athlete status or timing, are hypothesis-generating [3]. Some blood pressure effects may not depend on nitrate [4]. One meta-analysis disclosed grants from Bayer and Roche and other drug-company ties, outside the review [7].