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Beetroot nitrate
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In one pass Beetroot, spinach, arugula, and celery contain nitrate.
Educational content, not medical advice — consult a clinician.
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Chapter 1
What it is
Beetroot, spinach, arugula, and celery contain nitrate. Eat enough and your blood pressure dips a little, and the same endurance effort costs slightly less, because the body ends up turning it into nitric oxide (), a molecule that relaxes blood vessels.
The first stop on this route is not in the blood vessels but on the tongue: bacteria on the back of the tongue turn nitrate into nitrite, and the body then turns nitrite into nitric oxide. Humans have no enzyme of their own to convert nitrate, so this step is left to the friendly bacteria in the mouth. Leafy greens are the main dietary source of nitrate.
The preservative added to processed meat belongs to the same family of ions, but it arrives with different companions and ends up with a different outcome.
The first stop on this route is not in the blood vessels but on the tongue: bacteria on the back of the tongue turn nitrate into nitrite, and the body then turns nitrite into nitric oxide. Humans have no enzyme of their own to convert nitrate, so this step is left to the friendly bacteria in the mouth. Leafy greens are the main dietary source of nitrate.
The preservative added to processed meat belongs to the same family of ions, but it arrives with different companions and ends up with a different outcome.
Mechanism · why station one is the tongue
The route is a short chain: the mouth (nitrate-reducing bacteria on the back of the tongue), then the blood, then the smooth muscle in the vessel wall.Saying the body outsources this step to bacteria is not a figure of speech. Mammals have no enzyme that reduces nitrate to nitrite; the bacteria living in the mouth do. Lundberg's 2008 review describes this as a real division of labor between humans and microbes.
Behind the old saying that dark vegetables are good for the heart, this is one mechanism that can be spelled out: leafy greens feed nitrate into this route (EFSA 2008).
Background · same ion, different companions
Nitrate in vegetables and the nitrate or nitrite added as a preservative to bacon, ham, and sausage are the same family of ions, in completely different settings.Vegetable nitrate arrives together with vitamin C, polyphenols, and other antioxidants, and travels the route that widens blood vessels and protects their lining. The health concern with processed meat comes mainly from nitrosamines, which form when nitrite reacts with amines during high-heat cooking, plus the salt and fat.
Same molecule, different companions, different outcome. Do not squeeze two dietary stories into one slogan that nitrate is bad or nitrate is good.
Chapter 2
How nitrate becomes nitric oxide
The body makes nitric oxide () by two routes, and beetroot uses the second.
The first is the classic route: an enzyme in the lining of blood vessels (eNOS) makes NO on the spot from arginine and oxygen. This is the route covered in the citrulline story, and it runs smoothly only when oxygen is plentiful.
The second is the enterosalivary circulation: after the nitrate you eat enters the blood, about a quarter of it is pulled back into the mouth by the salivary glands, bacteria on the tongue turn it into nitrite, and after you swallow, the nitrite becomes NO. The lower the oxygen and the more acidic the surroundings, the better this route works, so it steps in just when the first route is struggling. That makes it and citrulline two different entry points; loading up on both does not simply add their effects together.
The first is the classic route: an enzyme in the lining of blood vessels (eNOS) makes NO on the spot from arginine and oxygen. This is the route covered in the citrulline story, and it runs smoothly only when oxygen is plentiful.
The second is the enterosalivary circulation: after the nitrate you eat enters the blood, about a quarter of it is pulled back into the mouth by the salivary glands, bacteria on the tongue turn it into nitrite, and after you swallow, the nitrite becomes NO. The lower the oxygen and the more acidic the surroundings, the better this route works, so it steps in just when the first route is struggling. That makes it and citrulline two different entry points; loading up on both does not simply add their effects together.
Mechanism · four steps of enterosalivary circulation
Lundberg 2008 describes the second route as an enterosalivary circulation:1. The nitrate you eat is absorbed from the small intestine into the blood.
2. About 25% of it is actively pulled back by the salivary glands, concentrated in saliva, and returned to the mouth.
3. Reducing bacteria on the back of the tongue turn nitrate into nitrite.
4. After you swallow, the acidic stomach and tissues short of oxygen reduce the nitrite further into .
What mammals lack is the enzyme for step 3. Antibacterial mouthwash kills that community of bacteria, and the chain breaks at that step.
Mechanism · why the two routes complement each other
The key difference: the second route works better the lower the oxygen and the more acidic the surroundings, and that is exactly when the classic eNOS route starts to struggle, as in working muscle or tissue short of blood. So the two routes do not duplicate each other; they complement each other. One is the main supplier when oxygen is plentiful, and the other fills in when oxygen is low and conditions are acidic (Lundberg 2008; Jones 2018).That is also why beetroot and citrulline should not simply be bought and stacked together. Citrulline raises the arginine pool (feeding the first route); beetroot raises the nitrate and nitrite pool (feeding the second). Both end at NO, but through different entry points and for different situations. Loading up on both does not make 1+1=2.
Chapter 3
The blood-pressure effect
Dietary nitrate nudges blood pressure down a little. That is real, and that is as far as it goes: a modest, mostly short-term effect, not a blood-pressure prescription.
The mechanism is clear: relaxes the vessel wall. But it only matters alongside eating more vegetables, eating less salt, and exercising regularly. People with normal blood pressure will barely notice it. For people who eat few vegetables and already have higher blood pressure, it is more likely to help a little, although long-term trials in this group are still scarce.
If you take blood-pressure medicine or nitrate drugs, mention it to your doctor before using it as a deliberate supplement.
The mechanism is clear: relaxes the vessel wall. But it only matters alongside eating more vegetables, eating less salt, and exercising regularly. People with normal blood pressure will barely notice it. For people who eat few vegetables and already have higher blood pressure, it is more likely to help a little, although long-term trials in this group are still scarce.
If you take blood-pressure medicine or nitrate drugs, mention it to your doctor before using it as a deliberate supplement.
Numbers · how far systolic pressure falls
Siervo 2013 (Journal of Nutrition), a pooling 16 trials and 254 people, found that inorganic nitrate or beetroot juice lowered systolic blood pressure by about 4.4 mmHg on average. Diastolic pressure fell by only about 1.1 mmHg, a small change that did not reach statistical significance. The effect depended on dose: more nitrate, a slightly larger drop.How should you read 4.4 mmHg? It is real, the mechanism is clear, and it replicates reasonably well. But it is modest, and it cannot replace blood-pressure medicine on its own. The trials were all short, so the effect is mostly short-term: it shows up after a single dose or within a few days. Whether it lasts over the long term and translates into fewer heart attacks and strokes, the evidence has not yet shown.
So its place is one small piece of the dietary puzzle, not a blood-pressure prescription.
Clinical · if you take blood-pressure medicine
This section is not medical advice. It only points out where to check with a doctor:Already on blood-pressure medicine: beetroot's effect adds to the drug's and may push your pressure a little lower than usual. Usually that is fine, but if your dose is being adjusted, adding a variable worth a few mmHg a day makes it harder for your doctor to judge the drug, so it is worth mentioning.On nitrate drugs (nitroglycerin, isosorbide mononitrate, often used for angina): these drugs supply directly. Dietary nitrate doses are far below the drug doses, but pushing both ends of the NO pathway at once calls for caution, so ask your doctor first.Reduced kidney function: the kidneys help process and excrete nitrate and nitrite, so the body handles them differently in serious kidney disease. Do not take large doses on your own.Infants: high-nitrate sources (some homemade vegetable purées, well water) carry a risk of methemoglobinemia, a condition in which the blood cannot carry oxygen properly, in young babies. That is a separate setting from adult exercise use, but it is worth knowing.
Eaten as food, beetroot is safe for the great majority of people. Once you take any drug that affects blood pressure or NO, treat it as a variable to tell your doctor about.
Chapter 4
Endurance performance
Beetroot became famous among endurance athletes because it makes the same exercise cost less oxygen. In controlled trials, oxygen use during moderate exercise goes down, and the time you can last at high intensity before exhaustion gets longer.
Recreational athletes and stop-and-go, high-intensity efforts are where the benefit shows most. For highly trained elite endurance athletes, the benefit is clearly smaller and sometimes not measurable: training has already pushed their blood vessels and mitochondria close to the ceiling, leaving little room for nitrate to add. Evidence for long time trials is even less consistent.
It works more like delaying the moment you crash than like making you faster outright.
Recreational athletes and stop-and-go, high-intensity efforts are where the benefit shows most. For highly trained elite endurance athletes, the benefit is clearly smaller and sometimes not measurable: training has already pushed their blood vessels and mitochondria close to the ceiling, leaving little room for nitrate to add. Evidence for long time trials is even less consistent.
It works more like delaying the moment you crash than like making you faster outright.
Numbers · who measured what
Larsen 2007 (Acta Physiologica), 9 well-trained men: after nitrate, cycling at the same load, their oxygen uptake fell from 2.98 to 2.82 L/min, about 5% less, and their gross efficiency rose from 19.7% to 21.1%.Bailey 2009 (J Appl Physiol), 8 people: after beetroot juice, the extra oxygen needed for each step up in power during moderate exercise (the oxygen-uptake gain) was 19% smaller (8.6 vs 10.8 ml·min⁻¹·W⁻¹), and time to exhaustion in high-intensity exercise was about 16% longer (675 vs 583 s).
McMahon's 2017 (Sports Medicine) put it plainly: nitrate more reliably improves exercise tolerance (time to exhaustion, how long you last); the evidence for time-trial performance (how fast you go) is much weaker.
Elite endurance athletes (peak oxygen uptake, VO₂peak, above roughly 65 mL/kg/min) gain clearly less (Jones 2018). It is a real but limited aid, not a gearbox.
Mechanism · why it saves oxygen
Same work, less oxygen: why? Jones 2018 (Annual Review of Nutrition) groups the leading explanations into two:1. Mitochondria make more economically: from nitrate appears to let mitochondria make the same amount of ATP with less leakage (reduced proton leak), so each breath of oxygen yields more energy.
2. Muscle contraction costs less energy: NO improves calcium handling and blood-flow distribution in fast-twitch (type II) fibers. Type II fibers are exactly the ones that run short of oxygen and tire easily, and they are where the nitrate-nitrite route helps most under low oxygen and low pH. That explains why the benefit concentrates in high-intensity, stop-and-go exercise.
Two honest caveats: the mitochondrial-efficiency finding has not replicated reliably in later work, and some experiments detect no change at the mitochondrial level. So why it saves oxygen is still not fully settled: the efficiency gain is real, but the details of the pathway are still argued over. As for why elites benefit less, one reasonable guess is that training has already pushed the blood flow, mitochondria, and blood-vessel function of their type II fibers close to the ceiling.
So thinking of beetroot as a little extra NO for a system that still has headroom is closer to the truth than thinking of it as an all-purpose performance booster.
Chapter 5
Don't kill the bacteria
The first stop on beetroot's route is the bacteria on your tongue, which leads to a counterintuitive result: antibacterial mouthwash can switch the whole effect off.
Humans have no enzyme of their own to convert nitrate; it all depends on the bacteria on the back of the tongue. Antibacterial mouthwash kills bacteria without distinguishing good from bad, so this outsourced production line stops too. Counting on beetroot to lower your blood pressure or help your training while rinsing with an antibacterial mouthwash every day is building with one hand and tearing down with the other. At the very least, do not use an antibacterial mouthwash around the time you take nitrate.
Humans have no enzyme of their own to convert nitrate; it all depends on the bacteria on the back of the tongue. Antibacterial mouthwash kills bacteria without distinguishing good from bad, so this outsourced production line stops too. Counting on beetroot to lower your blood pressure or help your training while rinsing with an antibacterial mouthwash every day is building with one hand and tearing down with the other. At the very least, do not use an antibacterial mouthwash around the time you take nitrate.
Numbers · mouthwash shuts the path
Kapil 2013 (Free Radical Biology and Medicine), 19 healthy people: using a 0.2% chlorhexidine mouthwash (a strong antibacterial agent) daily for 7 days cut the mouth's ability to turn nitrate into nitrite by about 90%, lowered plasma nitrite by about 25%, and raised systolic and diastolic blood pressure by about 2-3.5 and 2 mmHg. The blood-pressure change was measurable after a single rinse and persisted over the following 6 days.The mechanism is simple: mammals have no nitrate-reducing enzyme of their own and rely entirely on the bacteria on the back of the tongue (Lundberg 2008). Kill those bacteria and dietary nitrate never gets to the nitrite step, so the downstream and the small drop in blood pressure disappear too.
Myth · superfood and detox
Two common exaggerations can be taken apart.Beetroot is a superfood that detoxes and purifies the blood: in the , systolic pressure fell only by about 4 mmHg (Siervo 2013). That is a real, modest effect, nothing super. The nitrate pathway has nothing to do with detox; that is a marketing word.
The more you drink, the better: the dose has a ceiling, and past the saturation point more juice brings no extra benefit; the numbers are in the chapter on dose and timing. Beetroot's value lies precisely in being verifiably modest: the mechanism is clear, and so is the ceiling. Hyping it as a miracle wastes the rare quality of being explainable.
Chapter 6
Practical use
The usable rules first. The dose is about 5-8 mmol of nitrate, roughly 310-500 mg, and one concentrated beetroot shot usually lands in that range. Nitrite in the blood peaks 2-3 hours after you drink it, so to help your exercise, drink it 2-3 hours before a race or training session, not in a gulp at the start line.
A single dose already has a measurable short-term effect; taking it for several days in a row is usually steadier. For most people, leafy greens come first, and concentrated juice second.
A single dose already has a measurable short-term effect; taking it for several days in a row is usually steadier. For most people, leafy greens come first, and concentrated juice second.
Numbers · the dose ceiling
One mmol of nitrate is about 62 mg. A concentrated beetroot shot contains about 400 mg, or 6.4 mmol, which falls inside the 5-8 mmol range.Wylie 2013 measured dose and response directly: nitrite in the blood peaked 2-3 hours after drinking, and at about 8.4 mmol of nitrate the performance benefit was already close to its maximum; doubling the dose to 16.8 mmol brought no extra benefit. More is not better; it is just more.
Food or supplement: a beetroot shot is precisely dosed and convenient, but eating enough arugula, spinach, beet greens, and lettuce every day also raises your nitrate pool, and brings fiber and other nutrients along with it. Vegetables first, concentrated juice second, is the more sensible order.
In practice · who it is worth trying for
Recreational endurance athletes, people in stop-and-go sports, and anyone who wants moderate exercise to feel a bit easier: a meaningful small boost. People with higher blood pressure who eat few vegetables: as one part of changing their diet. Elite endurance athletes hoping it will win them results: do not expect much; the benefit is likely too small to measure (Jones 2018).Two things not to forget. Do not kill the bacteria with antibacterial mouthwash. And beetroot uses a different entry point from citrulline: the two complement each other, but there is no need to stack both, so try each on its own before reaching for the whole bundle.
This page is general education, not medical advice. Beetroot as food is safe for the great majority of people, but if you take blood-pressure or nitrate medicine, have kidney disease, or are pregnant or breastfeeding, check with your doctor before using it as a deliberate supplement.
References · 9
- Lundberg, J. O., Weitzberg, E., & Gladwin, M. T. (2008). The nitrate-nitrite-nitric oxide pathway in physiology and therapeutics. Nature Reviews Drug Discovery, 7(2), 156-167. 10.1038/nrd2466
- EFSA Panel on Contaminants in the Food Chain. (2008). Nitrate in vegetables — scientific opinion. EFSA Journal, 6(6), 689. Leafy vegetables (including spinach) are major dietary nitrate sources; dietary nitrate from vegetables is part of the nitrate-nitrite-nitric-oxide pathway. 10.2903/j.efsa.2008.689
- Jones, A. M., Thompson, C., Wylie, L. J., & Vanhatalo, A. (2018). Dietary nitrate and physical performance. Annual Review of Nutrition, 38, 303-328. 10.1146/annurev-nutr-082117-051622
- Siervo, M., Lara, J., Ogbonmwan, I., & Mathers, J. C. (2013). Inorganic nitrate and beetroot juice supplementation reduces blood pressure: a systematic review and meta-analysis. The Journal of Nutrition, 143(6), 818-826. Dietary nitrate modestly lowered blood pressure (effect strongest from beetroot/leafy-green nitrate). 10.3945/jn.112.170233
- Larsen, F. J., Weitzberg, E., Lundberg, J. O., & Ekblom, B. (2007). Effects of dietary nitrate on oxygen cost during exercise. Acta Physiologica, 191(1), 59-66. 10.1111/j.1748-1716.2007.01713.x
- Bailey, S. J., Winyard, P., Vanhatalo, A., Blackwell, J. R., DiMenna, F. J., Wilkerson, D. P., Tarr, J., Benjamin, N., & Jones, A. M. (2009). Dietary nitrate supplementation reduces the O2 cost of low-intensity exercise and enhances tolerance to high-intensity exercise in humans. Journal of Applied Physiology, 107(4), 1144-1155. 10.1152/japplphysiol.00722.2009
- McMahon, N. F., Leveritt, M. D., & Pavey, T. G. (2017). The effect of dietary nitrate supplementation on endurance exercise performance in healthy adults: A systematic review and meta-analysis. Sports Medicine, 47(4), 735-756. 10.1007/s40279-016-0617-7
- Kapil, V., Haydar, S. M. A., Pearl, V., Lundberg, J. O., Weitzberg, E., & Ahluwalia, A. (2013). Physiological role for nitrate-reducing oral bacteria in blood pressure control. Free Radical Biology and Medicine, 55, 93-100. 10.1016/j.freeradbiomed.2012.11.013
- Wylie, L. J., Kelly, J., Bailey, S. J., Blackwell, J. R., Skiba, P. F., Winyard, P. G., Jeukendrup, A. E., Vanhatalo, A., & Jones, A. M. (2013). Beetroot juice and exercise: pharmacodynamic and dose-response relationships. Journal of Applied Physiology, 115(3), 325-336. 10.1152/japplphysiol.00372.2013