Beetroot Juice for Runners: Dose, Timing, and Who It Helps

Beetroot juice is one of the few sports supplements with genuine evidence behind it. The International Olympic Committee 2018 consensus statement on supplements puts it on a very short list: "only a few (including caffeine, creatine, specific buffering agents and nitrate) have good evidence of benefits."

The complication is that the benefit is small, and it is not evenly distributed. Pooled across 80 studies, nitrate supplementation beat placebo by d = 0.174 — the authors call that effect "objectively small" — and in two subgroups it was not observed at all: well-trained endurance athletes and women. So the useful question is not "does beetroot juice work." It is "does it work for me, and how much do I actually need to swallow."

The dose is the entire point

That figure comes from an umbrella review covering 20 systematic reviews, 180 primary studies and 2,672 participants (Poon et al., Sports Medicine, 2025). It found improved time to exhaustion (SMD 0.33; 95% CI 0.19-0.47), "with subgroup analyses indicating more pronounced improvements when a minimum dose of 6 mmoL/day (372 mg/day) and chronic (> 3 days) supplementation protocol was implemented."

The same review found effects on total distance covered (SMD 0.42), muscular endurance (SMD 0.48), peak power output (SMD 0.25) and time to peak power (SMD -0.76). Every other performance measure it looked at showed no significant improvement.

Read the quality rating alongside the result. The authors grade their own evidence base: "The AMSTAR-2 ratings of most included reviews ranged from low to critically low." That is not a critic saying it. That is the review team.

One more honest detail about the number. Six millimoles is a floor, not a target. The trials that actually found something mostly used more: 8.4 mmol per day in the two recreational-runner studies, 8.2 mmol in the sprint study. The one trial here that landed near 7 mmol is also the one that found nothing in well-trained athletes.

What 372 mg looks like as food

Nitrate is nitrate. Beetroot dominates this research area not because it is the richest source but because, as one of the lab groups that tested these products put it, beets "are readily juiced." A 2026 review of nitrate-rich vegetables says it directly: "many commonly consumed vegetables, particularly leafy and stem varieties, contain comparable or higher levels of nitrates."

Fresh vegetables: nitrate content and the amount needed to reach 372-496 mg

Vegetable (raw, fresh weight)	Nitrate per 100 g	Amount to reach the dose
Beetroot	250-400 mg	93-198 g (roughly 1-2 medium beets)
Rocket / arugula	300-600 mg	62-165 g
Spinach	250-500 mg	74-198 g
Lettuce	100-400 mg	93-496 g
Celery	150-250 mg	149-331 g
Brassicas (cabbage, kale, broccoli, cauliflower)	50-250 mg	149-992 g

Three limits on that table. The ranges come from a single narrative review, and other published figures for beetroot are lower, so treat them as one source's range rather than a settled value. They apply to raw, fresh produce only — cooking, storage and juicing all move the number. And they cannot be converted into powder figures by multiplying for water loss, because nobody has published the nitrate loss rate for dehydration.

The width of each range is not sloppiness. It is the real uncertainty created by soil nitrogen and storage conditions, which is also why the same product differs between batches. For where these vegetables fit into everyday eating rather than race week, see the daily nutrition guide for runners.

Timing: aim for two to three hours

The original trial protocols mostly dosed 2 to 3 hours before the effort: the two recreational-runner studies used 2 hours, the well-trained study used 2.5. Pharmacokinetic data cited in a 2019 survey of beetroot products puts the peak in plasma nitrite 2 to 3 hours after ingestion for most of them.

Manufacturer guidance is looser. One major brand opens the window wider, telling users to take a shot 1 to 3 hours before exercise and to build nitrate levels with a daily shot for up to six days before an event. The loading advice matches the research. The one-hour end of that window does not. Plan the last dose 2 to 3 hours out, which for most races means taking it with or just after breakfast — the race morning planner will place it against your wake-up and start time, and the pre-race meal calculator covers what else goes in that window.

Who it works for, and who it does not

A meta-analysis pooling 80 studies (Senefeld et al., Medicine and Science in Sports and Exercise, 2020) sets the baseline. Overall effect: d = 0.174 (95% CI 0.120-0.229, P<0.001), described by the authors as objectively small. The population where they found "a clear ergogenic effect" was specific: "recreationally active, young, healthy men."

Three subgroup findings matter more than the headline. The effect was "not observed in studies with only women" (n = 6; d = 0.116; 95% CI, -0.126 to 0.358; P = 0.347), and "not observed in well-trained endurance athletes" — those at 65 mL/kg/min or above (n = 26; d = 0.021; 95% CI, -0.103 to 0.144; P = 0.745). It was also "not modulated by FiO2 (hypoxia vs normoxia)."

If you are already fast, this is probably not your lever

A single trial illustrates what that null looks like up close. Ten well-trained men (VO2max 66 ± 7 mL/kg/min, 10K personal bests of 36 ± 2 minutes) took roughly 7 mmol 2.5 hours before testing. Their blood chemistry responded exactly as the theory predicts: plasma nitrite rose from 61 to 473 nmol/L (P<0.001). Their performance did not follow.

Time to exhaustion showed no difference (P=0.5). The 10 km time trial showed no difference (P=0.6). The 11-second gap that did appear was smaller than the 51-second minimum important difference the researchers had set in advance, and only 3 of the 10 athletes showed a possibly beneficial change. That is a null result, not a harmful one — the point estimates leaned slightly toward nitrate, they just meant nothing.

One caveat on that study and one release from it. It was run in simulated altitude, and its conclusion sentence ends "in normobaric hypoxia", so on its own it says nothing about sea level. But the 80-study analysis above found the effect was not modulated by oxygen availability, and its 65 mL/kg/min threshold lands exactly on these athletes' 66. Taken together, the finding travels down to sea level.

A second, independent meta-analysis lands in the same place from a different dataset. Pooling 118 studies of nitrate-rich and polyphenol-rich foods, it found that well-trained males — those at 65 ml/kg/min or above — "exhibited small, significant benefits following polyphenol, but not nitrate consumption." Its conclusion is blunter still: "Highly trained endurance athletes do not appear to benefit from consuming nitrate-rich foods but may benefit from polyphenol consumption." Two pooled analyses, two datasets, the same answer for fast runners.

The evidence base is men, and the female subgroups came back null

This needs saying plainly because most beetroot articles skip it. Every original beetroot trial cited on this page recruited men only: thirteen men, fourteen men, ten men. The dosing protocol above was established in male participants.

Two independent meta-analyses then looked for an effect in women and did not find one. The 80-study analysis reports it "not observed in studies with only women" (P = 0.347). A separate 118-study analysis of nitrate-rich and polyphenol-rich foods states that "no effect of nitrate or polyphenol consumption was found in females."

A null in a small subgroup is not proof that nothing happens; six women-only studies is a thin base and the confidence interval crosses zero in both directions. But it is what the evidence says today, and the honest version is this: if you are a woman, there is currently no published basis for expecting the benefit that the male data supports.

A better VO2max is not a faster 10K

Two studies from the same research group, published the same year, make this distinction unavoidable. Both used 8.4 mmol per day for 3 days in recreational runners, with the final dose 2 hours before testing.

The physiology study (n=13) found real improvements: VO2max 46.6 ± 6.4 versus 45.1 ± 5.8 mL/kg/min (P=0.022), velocity at VO2max 14.5 ± 0.8 versus 13.9 ± 1.0 km/h (P=0.024), and peak velocity 15.5 ± 1.1 versus 15.2 ± 1.2 km/h (P=0.038).

The performance study (n=14) put the same protocol into a 10 km time trial. Result: 50.1 ± 5.3 minutes on beetroot versus 51.0 ± 5.1 on placebo, P=0.391. Not significant. The first 5 km were significantly faster (P=0.027), and 10 of the 14 runners finished quicker, but the finishing times as a group did not separate. Treat improved lab numbers and improved race times as two separate claims, because in this pair of studies they were.

How to read a beetroot label

Here is the structural problem with this whole category: there is currently no agreed unit of measure that lets a shopper compare one product against another. That statement is not an accusation, and the two sides of the shelf get there for different reasons, which is why they should not be lumped together.

On the beetroot side the cause is the raw material. Nitrate content tracks soil nitrogen, growing conditions and storage, so batches genuinely differ and a printed number can drift away from what is in the bottle. On the tart cherry side the cause is different and harder: the measurement method itself is not standardised, on top of the same raw-material variation.

Independent testing shows the scale. A 2019 study bought 45 lots of 24 different beetroot products and measured them by HPLC. Between batches of the same product, the mean coefficient of variation was 30% ± 26% (range 2-83%). Between products there was "almost a 50-fold range in NO3- content", and only five of the 24 products consistently delivered at least 5 mmol per serving.

A 2025 round of independent testing by a consumer testing lab found the same shape. One serving of a beetroot product could deliver "as much as 495.7 mg to as little as 4.3 mg of nitrate - more than a 100-fold difference." Juices ran about 200 to 300 mg per 8 fl oz cup; one concentrated shot came in near 500 mg. That lab also notes that clinical trials have typically used "around 300 mg to 600 mg daily", which brackets the 372 mg floor.

Since milligrams are not comparable across the shelf, compare something that is: how many servings of a given form you would have to get through to reach the dose the studies used.

Servings needed to reach 372-496 mg of nitrate (6-8 mmol)

Form	One serving	Servings to reach the dose	What the number rests on
Sports beetroot shot (Beet It Sport Nitrate 400)	70 mL	1	Claims 400 mg (6.45 mmol); independently measured at 6.41 ± 0.60 mmol
Bulk juice, richest tested (Lakewood Organic)	by volume	160-213 mL	Measured 18.77 ± 1.59 mmol per 500 mL
Bulk juice, weakest tested (Love Beets)	by volume	896-1194 mL	Measured 3.35 mmol per 500 mL
Beetroot powder (HumanN SuperBeets)	5 g scoop	about 6-8 scoops	Measured 1.03 mmol per serving; no nitrate figure published by the brand
Nitrate energy gel (Beet It top-up)	1 gel	3.7-5.0	Labelled 100 mg; sold as an in-race top-up, not the main dose
Raw beetroot	fresh weight	93-198 g	One review's range of 250-400 mg per 100 g fresh weight

Three limits on that table. The measured values come from samples bought between September 2017 and June 2018 by a single laboratory, so they describe those lots, not the bottle in your hand. Given a between-batch coefficient of variation that reached 83% in that dataset, no single figure here should be read as a guarantee. And no comparable retest has been published since, so there is no way to say whether the industry has improved.

Note the spread among ordinary supermarket juices: 160 mL at one end, nearly 1.2 litres at the other, a 7.5-fold difference in how much you have to drink for the same dose. "Drinking beetroot juice" is not an intervention. The specific product is the intervention.

One honest caveat on the yardstick itself: nitrate is the component that can be measured and compared across products, but whether it accounts for the whole of what beetroot juice does is not settled.

The product that checks out, and the one you cannot check

This is not a story about brands being untrustworthy. In that 2019 dataset one product lines up exactly as it should: label claim 400 mg, independent measurement 6.41 ± 0.60 mmol, which is about 397 mg. Claim and assay agree.

Two footnotes keep that clean. The lab tested it under an earlier product name, and the identification rests on the arithmetic matching (400 divided by 62 equals 6.45 mmol, the exact claimed value in the paper) rather than on any announcement from the company. And the 400 mg lives in the product description, not in the regulated nutrition panel — nitrate does not appear on the panel at all.

The opposite case is not fraud either, which is exactly what makes it instructive. HumanN does not publish a nitrate figure for SuperBeets anywhere on its product page; what occupies that space is "1 scoop = 40X the functional benefits of fresh beets." There is no milligram claim to be wrong about. The problem is that you cannot verify what you took.

That is not one brand’s quirk. Of the six powders in the same 2019 testing round, not one stated a nitrate figure on its label, and not one delivered 5 mmol in a single serving. Measured contents ran from 0.43 to 2.56 mmol per serving, so the weakest of them would take fourteen scoops or more to reach the research dose. The form that most often omits the number is also the form least likely to contain enough of it.

A three-item check before you buy

• Look for milligrams or millimoles per serving. A 2026 analysis of 18 nitrate and beetroot supplements on the European market found 27.8% state no dose at all, and only 38.9% match protocols established in the scientific literature.
• Check the number against 372 mg. In that same analysis, 61.1% of products carried 300-500 mg per serving, so a compliant product does exist on most shelves.
• Treat substitute units as marketing. "Forty times the benefit of fresh beets" and "made from N beets" cannot be converted into a dose, because there is no legal nitrate content for one beet.

On cost, only the structural picture is stable enough to be worth printing. Powders were often the most cost-effective route to a given amount of nitrate in the 2025 testing round, despite being the form most likely to omit the number. Among supermarket juices, the volume needed for one dose spans that 7.5-fold range, and the cost gap runs with it.

The thirty-second way to waste every dose

Nitrate does nothing on its own. Bacteria living at the back of your tongue reduce it to nitrite; that is the step your body cannot do efficiently by itself. Remove the bacteria and the chain breaks.

In a 7-day study, antibacterial chlorhexidine mouthwash cut oral nitrite production by 90% (p<0.001) and plasma nitrite by 25% (p=0.001), and pushed systolic and diastolic blood pressure up by 2 to 3.5 mmHg. The effect appeared within one day of disrupting the oral bacteria. The authors concluded that "the recycling of endogenous nitrate by oral bacteria plays an important role in determination of plasma nitrite levels."

Be precise about what that means. The study measured blood pressure and nitrite, not running performance, so nobody has published what mouthwash does to a race time. What can be said is that it cuts the conversion pathway beetroot juice depends on. The action is simple: skip antibacterial mouthwash on loading days and on race morning.

Race week, step by step

1. Check the gate first. If your VO2max is around 65 mL/kg/min or higher, the pooled data says d = 0.021 and P = 0.745 — expect nothing. If you are a woman, the female subgroups came back null in two independent analyses.
2. Fix the dose before choosing a product. At least 6 mmol (372 mg) per day. Work out how many servings of your specific product that takes, using the table above or the label figure if there is one.
3. Load for more than three days. That is the boundary the umbrella review identified; one brand suggests up to six days before an event, which sits inside the same window.
4. Take the final dose 2 to 3 hours before the start. Not one hour, whatever the bottle says.
5. Drop antibacterial mouthwash for the whole loading period. This is the cheapest thing on the list and the easiest to get wrong.
6. Rehearse it in a hard training session first. This is the Australian Institute of Sport's instruction rather than a suggestion of ours: athletes intending to use nitrate before competition "are advised to first practice in training". Individual response also varies widely, which the IOC consensus states outright: responses "may vary widely between individuals because of factors that include genetics, the microbiome, and habitual diet."
7. Do not plan around it for recovery. Post-marathon, the trial evidence is null.
8. Settle the medical questions first. Blood pressure medication, nitrate drugs, PDE-5 inhibitors or kidney disease make this a conversation with a doctor before it is a training decision.

It did not help marathon recovery

Thirty-four marathon runners took beetroot juice or an isocaloric placebo for three days after a marathon. Countermovement jump and maximal voluntary contraction both dropped after the race, with no difference between groups (P>0.05). Muscle soreness: no difference (P=0.694). Interleukin-6: no interaction (P=0.213). Leukocytes, creatine kinase, AST and hs-CRP: no differences. The conclusion sentence is blunt — "Beetroot juice did not attenuate inflammation or reduce muscle damage following a marathon."

One limit on how far to push that. The trial answered a specific question, clearly: inflammation and muscle damage after a marathon. A 2024 review comparing beetroot juice against nitrate salts raises the separate possibility that the juice carries advantages the salts do not, recovery among them, attributed to the wider spectrum of compounds it contains — while stating that "significant limitations to published studies directly comparing BRJ and NIT make it quite challenging to draw any firm conclusions". A null result for post-marathon recovery is not a proven absence of any recovery role.

So this is a pre-race tool with a null result on the recovery side. The recovery evidence points at a different compound entirely, and there is a genuine reversal buried in it: the polyphenol route appears to work best in exactly the well-trained athletes where nitrate stops working. That comparison is laid out in the tart cherry juice guide.

The dose sits above the regulatory limit, and that needs both halves

Almost no running article raises this, so here it is with the context attached rather than as a scare. The acceptable daily intake for nitrate is 3.7 mg per kilogram of body weight per day, set by the SCF in 1997 and JECFA in 2002. For a 70 kg adult that is 259 mg. The protocol on this page, 372 to 496 mg a day, is 1.4 to 1.9 times that figure — and the trials cited earlier went higher still: the 8.4 mmol used in the two recreational-runner studies is about 521 mg, roughly twice the ADI for a 70 kg adult. Put the other way round, 6 mmol only equals the ADI at a body weight of about 100 kg.

Where the number came from matters. JECFA derived it from a no-observed-effect level of 370 mg/kg body weight per day in rats, divided by a safety factor of 100. The hazards behind it are methaemoglobinaemia in the short term and endogenous N-nitroso compound formation in the long term. It is a toxicology figure for an additive, not a dosing guideline for vegetables or for sport.

The committee that set it says as much. Data on the putative health benefits of nitrate "were not assessed, as this is not a safety issue and is therefore not within the purview" of the committee. EFSA, re-evaluating the additive in 2017, found that "it was not possible to derive a single value of the ADI from the available data", while also concluding there was "insufficient evidence to withdraw this ADI". Neither sentence is an endorsement and neither is a retraction.

Then the line that changes how the 1.4-to-1.9 multiple reads. The same EFSA opinion states that "if all sources of exposure to dietary nitrate are considered (food additive, natural presence and contamination), the ADI would be exceeded for all age groups at the mean and the highest exposure." Being over the ADI is not a place beetroot juice takes you on your own. It is roughly where people who eat vegetables already are.

A unit warning, because this is where the arithmetic usually breaks. The 3.7 mg/kg figure is expressed as nitrate ion, the same basis as the millimole conversion used throughout this page, so the two can be divided directly. The same committee also expressed the limit as 5 mg/kg on a sodium nitrate basis. Those are two ways of writing one limit, not two limits, and only the nitrate-ion version can be set against a dose worked out as millimoles times 62.

What is genuinely unresolved is the long run, and both sides of it are on the record. A systematic review on the benefits and risks of beetroot juice warns that drinking it "may easily increase nitrate intake above the acceptable daily intake, which is known to stimulate the endogenous formation of N-nitroso compounds", then adds that "compared to studies on the beneficial effects, the amount of data and literature on the negative effects of BRJ is rather limited, and should be increased in order to perform a balanced risk assessment."

Against that, JECFA's own review of the epidemiology did not find the association you would expect if dietary nitrate were driving cancer risk. A Dutch cohort followed for 6 years "found no significant association between the incidence of gastric cancer and intake of nitrate from food or drinking-water", and across the case-control studies of dietary nitrate "no association was found with oral, oesophageal, gastric or testicular cancer." The Australian Institute of Sport calls the older safety concerns "in any case disputed", while stating in the same document that "chronic use of nitrate supplements has not been well studied."

So the honest summary is neither "safe" nor "risky". It is that the evidence for short-term performance is considerably stronger than the evidence for long-term safety, and that a race-week protocol is a different proposition from a habit you keep for a decade.

For scale in the other direction: the Australian Institute of Sport estimates average dietary nitrate intake among adults in the US, Europe and Australia at 1-2 mmol per day, about 60-120 mg, with vegetables supplying roughly 80% of it. Measured against that estimate, the research dose is roughly 3 to 8 times an ordinary day's intake.

Those two official statements do not fit together, and both are official. The European regulator, above, says average intake already exceeds the ADI once every source is counted; a national sports institute puts typical adult intake well below it. We have no basis for deciding between them, so both are given here as published — do not read them as confirming each other.

Side effects: red output, and a stomach to test in training

Red urine and red stools are normal

Beetroot pigment can tint urine and stools pink or red. The Australian Institute of Sport puts it plainly: "The consumption of beetroot/juice may cause a temporary pink coloration of urine and stools. This is a harmless side-effect." Some people get it and some do not. The proportions usually quoted are repeated from older literature rather than measured, so they are not worth attaching a number to.

It is not a sign that your kidneys or liver are struggling. The research concluded that it "does not arise from deficiencies in hepatic metabolism or renal excretion" of the pigments, and that the variation between people is driven largely by stomach acidity and gastric emptying rate, with absorption of the pigment in the colon doing the rest. It is reported more often in people who are iron deficient or have malabsorption.

One boundary is worth keeping. Red urine has other causes, and beeturia appears in clinical references precisely because it sits on the differential for red urine. If red urine turns up when you have not eaten beetroot, or carries on after you stop, that is a question for a doctor rather than a footnote in a running guide.

The gut, and the one instruction worth following

The same official fact sheet says: "Beetroot juice, particularly in concentrated form and larger doses, sometimes causes mild gastrointestinal discomfort. Athletes who are inclined to use nitrate supplementation pre-competition are advised to first practice in training." That second sentence is where the rehearse-in-training step of the race-week protocol comes from: a national sports institute, not us.

How common is it? No published figure exists. "Beet burps" is community vocabulary with no counterpart in the literature: searches for reported rates of belching, bloating or gastrointestinal distress with beetroot or dietary nitrate come back empty. The only quantified signal found came from a four-arm trial in which gastrointestinal distress was greater with beetroot juice plus caffeine than with placebo (by 2.4 ± 3.6 a.u.; p < 0.05). That arm combined the two, so it says nothing about juice on its own.

If you juice raw beetroot yourself, handle it like any other raw produce. Finland recorded a cluster of gastrointestinal illness outbreaks in 2010 linked to raw grated beetroot served in institutional canteens, where no common foodborne pathogen or toxin was ever identified and all tested samples were of poor microbiological quality. That was catering-scale raw beetroot with an undetermined cause, not juice and not supplements. The transferable part is only about freshness and handling.

When this becomes a medical question

The best-documented physiological effect beetroot juice has is lowering blood pressure. In a trial of 18 men with normal blood pressure, doses of 100, 250 and 500 g lowered systolic (P < 0.01) and diastolic (P < 0.001) pressure across 24 hours in a "near dose-dependent manner". For most people that is a bonus. For some it is a complication.

• Blood pressure medication, or naturally low blood pressure. No trial has tested dietary nitrate alongside antihypertensive drugs, so an additive effect is a mechanistic expectation, not a measured one. Worth raising with whoever writes the prescription.
• Nitrate drugs or PDE-5 inhibitors. The label for sildenafil contraindicates it with "nitric oxide donors, such as organic nitrates or organic nitrites in any form", because it "was shown to potentiate the hypotensive effect of nitrates". Dietary nitrate is an inorganic nitrate ion and is not the drug class that label names, and no study has tested the combination in either direction. Absence of evidence is not evidence of safety, which makes this a question for a doctor rather than a self-assessment.
• Chronic kidney disease or dialysis. The one relevant dataset is eight haemodialysis patients given a single 70 mL, 400 mg dose: plasma nitrate exposure, both area under the curve and peak concentration, was significantly higher than in healthy volunteers, while blood pressure and plasma potassium were unaffected and no adverse events were reported. A single dose in eight people tracked for 44 hours says nothing about repeated use.
• Never swap nitrate for nitrite. The AIS warns that nitrate salts used as supplements carry a greater risk of misjudging dosages, and that athletes who mistakenly or deliberately use sodium or potassium nitrite expose themselves to "toxic effects such as methemoglobinaemia". The two words differ by one letter. Stay with food-form juice or concentrate.
• Not for infants. EFSA's contaminants panel notes that infants and children with bacterial gastrointestinal infections are more sensitive to nitrate, and advised against feeding spinach to those children. Badly stored cooked vegetables can also convert nitrate to nitrite in situ.

Each of those gaps is a search that came back empty rather than a question nobody thought to ask: no published trials of dietary nitrate with antihypertensives, none with PDE-5 inhibitors or organic nitrate drugs, and no long-term safety data on nitrate supplementation.