Beetroot is one of the most researched natural nitric oxide boosters on the planet. But does the science actually hold up under scrutiny? We dug into the clinical evidence to separate fact from hype.
Updated: March 28, 2026 · By the NitricHealthLab Research Team
Quick Take
Yes, beetroot is one of the most well-studied natural nitric oxide boosters available. The dietary nitrates found in beets convert to nitric oxide through a completely separate biological pathway from amino acid-based precursors like L-arginine and L-citrulline. This means beetroot does not just "support" NO production — it provides your body with an independent, alternative route to make it. Dozens of peer-reviewed studies and multiple meta-analyses confirm meaningful benefits for blood pressure, exercise performance, blood flow, and cognitive function.
That said, the details matter. How much beetroot you need, what form is most effective, and how your daily habits can completely block the pathway — these nuances make the difference between getting real results and wasting your time. Let us break down exactly what the research shows.
The Science
To understand why beetroot is so effective, you need to know that your body has two distinct pathways for producing nitric oxide. Most people — including many supplement companies — only talk about one of them.
Pathway 1: The L-Arginine/eNOS Pathway. This is the "classical" route. The amino acid L-arginine is converted to nitric oxide by an enzyme called endothelial nitric oxide synthase (eNOS) inside the cells lining your blood vessels. L-citrulline supplements work by converting to L-arginine in the kidneys, feeding this pathway. It is enzyme-dependent and declines significantly with age — which is why men over 35 often struggle with NO production even when they eat adequate protein.
Pathway 2: The Nitrate-Nitrite-NO Pathway. This is where beetroot shines. It works through an entirely different mechanism that does not require eNOS at all. Here is how it works, step by step:
Beetroot is exceptionally rich in inorganic nitrate (NO3-). When you eat beets or drink beetroot juice, these nitrates enter your bloodstream through the gastrointestinal tract and are absorbed rapidly.
About 25% of the circulating nitrate is actively taken up by your salivary glands and concentrated in your saliva — reaching levels 10-20 times higher than in your blood plasma. Your body is deliberately routing nitrate to your mouth.
Specific species of bacteria living on the back of your tongue (particularly in the deep crypts of the tongue's surface) reduce nitrate (NO3-) to nitrite (NO2-). Humans cannot perform this conversion on their own — we are entirely dependent on these oral bacteria. This is a symbiotic relationship that has evolved over millennia.
When you swallow the nitrite-enriched saliva, the acidic environment of the stomach converts some nitrite directly to NO. Additional nitrite enters the bloodstream, where it is reduced to nitric oxide in tissues under low-oxygen conditions — precisely where NO is needed most, such as working muscles during exercise.
This pathway is remarkable because it actually becomes more efficient under the exact conditions where the eNOS pathway struggles: low oxygen, acidic pH, and reduced blood flow. During intense exercise, when your muscles are oxygen-starved and generating lactic acid, the nitrate-nitrite-NO pathway kicks into higher gear. It is a backup system that complements the primary eNOS pathway beautifully.
The practical implication? If you are only using L-arginine or L-citrulline for nitric oxide support, you are only activating one of your body's two NO production systems. Adding beetroot (or dietary nitrates in general) activates the second pathway, giving you a dual-source approach to nitric oxide production.
Evidence Review
Beetroot's effects on nitric oxide are not theoretical. They are backed by a substantial and growing body of clinical research. Here are the key findings across five major health domains.
This is the most extensively studied benefit of dietary nitrate from beetroot, and the evidence is compelling.
A 2013 meta-analysis published in The Journal of Nutrition analyzed 16 randomized controlled trials and found that inorganic nitrate (primarily from beetroot juice) reduced systolic blood pressure by an average of 4.4 mmHg and diastolic blood pressure by 1.1 mmHg. A more recent 2017 meta-analysis in Advances in Nutrition confirmed these findings across 22 trials, reporting systolic reductions of 3.55 mmHg.
A larger 2018 meta-analysis looking at 43 randomized trials found systolic reductions ranging from 3 to 10 mmHg, with the most pronounced effects seen in people with higher baseline blood pressure. This is clinically meaningful — a sustained 5 mmHg reduction in systolic blood pressure is associated with a 7% reduction in all-cause mortality at the population level.
The mechanism is straightforward: nitric oxide produced from dietary nitrate causes vasodilation (blood vessel relaxation), reducing peripheral vascular resistance. The effect typically begins within 2-3 hours of consumption and can last 6-8 hours after a single dose. With regular daily intake, the blood pressure benefits become sustained.
Importantly, beetroot juice does not appear to cause dangerous drops in blood pressure in people with normal readings. The effect is more pronounced in those with elevated levels, suggesting a degree of self-regulation. However, if you are on blood pressure medication, consult your doctor before adding large amounts of beetroot to your routine.
Beetroot juice has become a staple in sports nutrition research, and for good reason.
A landmark 2009 study in the Journal of Applied Physiology by researchers at the University of Exeter found that beetroot juice supplementation reduced the oxygen cost of submaximal exercise by approximately 5% and extended time-to-exhaustion by 16%. These were stunning numbers for a natural food intervention.
Subsequent research has been slightly more conservative but still positive. A 2017 meta-analysis in the Journal of the International Society of Sports Nutrition reviewing 76 studies found that dietary nitrate supplementation (primarily from beetroot) improved time-to-exhaustion by 2-3% on average. While 2-3% may sound small, in competitive athletics, this margin is enormous — it can be the difference between a podium finish and not qualifying.
The performance benefits appear to stem from two mechanisms: (1) improved efficiency of muscle contraction, meaning less oxygen is needed for the same workload, and (2) enhanced blood flow to working muscles, improving oxygen and nutrient delivery. The effects are most pronounced in activities lasting 5-30 minutes at high intensity, and in recreational athletes rather than elite competitors (whose NO systems are already highly optimized through training).
For men over 40 who have noticed declining exercise capacity, beetroot's ability to improve oxygen efficiency is particularly relevant. It partially compensates for the reduced NO production that comes with age, helping you get more from each workout.
Nitric oxide's primary role is vasodilation — relaxing and widening blood vessels to improve blood flow. Multiple studies have directly measured beetroot's impact on this process.
A 2015 study in Hypertension demonstrated that daily beetroot juice consumption for four weeks improved flow-mediated dilation (FMD) — the gold standard measure of endothelial function — by 20% in healthy volunteers. Arterial stiffness, measured by pulse wave velocity, was also significantly reduced.
Research in patients with peripheral arterial disease (PAD) has shown that beetroot juice improves walking distance and reduces the pain associated with poor leg circulation. A 2020 study in Circulation Research found that acute beetroot juice consumption increased calf muscle oxygenation during exercise in PAD patients, demonstrating that the nitrate-derived NO was reaching exactly where it was needed.
These findings have particular relevance for men experiencing signs of low nitric oxide like cold extremities, slow recovery, or declining sexual performance — all of which are driven by impaired blood flow.
Your brain consumes roughly 20% of your body's oxygen despite representing only 2% of your body weight. Adequate cerebral blood flow is non-negotiable for optimal cognitive performance, and nitric oxide is the molecule that regulates it.
A 2011 study published in Nitric Oxide: Biology and Chemistry used MRI to demonstrate that a single dose of beetroot juice increased blood flow to the frontal lobes of older adults — specifically to the white matter regions associated with executive function and working memory. These are the brain areas most vulnerable to age-related blood flow decline.
A 2016 study in The Journals of Gerontology went further, showing that combining beetroot juice with moderate exercise produced greater improvements in brain network connectivity than exercise alone. The researchers noted that the combination mimicked the brain connectivity patterns of younger adults.
While the cognitive research is still developing, the mechanism is well-established: more NO means more cerebral blood flow, which means better oxygen and glucose delivery to neurons. For men experiencing brain fog or declining mental sharpness alongside other signs of low nitric oxide, dietary nitrate supplementation through beetroot is a research-supported strategy worth considering.
Beyond blood pressure, beetroot-derived nitric oxide has broader cardiovascular benefits. Arterial stiffness — a key marker of cardiovascular aging — increases as we get older, driven in part by declining NO levels. Stiff arteries mean the heart has to work harder, and they are independently associated with higher risk of heart attack and stroke.
A 2015 clinical trial in Clinical Nutrition found that just two weeks of daily beetroot juice significantly reduced arterial stiffness in overweight older adults, as measured by aortic pulse wave velocity. A 2019 study in Heart replicated these findings in patients with heart failure, showing improved exercise capacity and reduced vascular resistance after beetroot supplementation.
Platelet aggregation (the tendency of blood cells to clump together, forming clots) is also inhibited by nitric oxide. Several studies have demonstrated that beetroot juice has anti-platelet effects, potentially reducing the risk of thrombotic events. A 2013 study in Free Radical Biology and Medicine showed that dietary nitrate consumption inhibited platelet aggregation within 3 hours of ingestion.
These cardiovascular benefits are cumulative and complementary. Better vasodilation, reduced stiffness, lower blood pressure, and inhibited platelet aggregation — together, they paint a picture of a food that genuinely supports heart health through multiple mechanisms.
Dosing
The effective dose of dietary nitrate used in most clinical research is approximately 6.4 mmol (400 mg) of inorganic nitrate per day. Here is what that translates to in practical terms:
Approximately 500 ml (about 17 oz) of regular beetroot juice provides roughly 6.4 mmol of nitrate. This is the volume used in many of the studies cited above. Drink it 2-3 hours before you want peak effects.
A 70 ml (2.4 oz) concentrated beetroot shot delivers the same ~6.4 mmol nitrate dose in a fraction of the volume. These are the most popular format in sports nutrition research because they are practical and precisely dosed.
Two to three medium-sized raw beets daily provide a comparable nitrate dose. However, nitrate content varies significantly depending on growing conditions, soil quality, and storage time, making precise dosing difficult with whole food alone.
Capsules and powders standardized for nitrate content offer the most consistent dosing. Quality varies widely between brands — look for products that specify the nitrate content per serving rather than just listing "beetroot extract" without quantification.
Timing matters. Plasma nitrite levels (the precursor to NO) peak approximately 2-3 hours after consuming dietary nitrate. For exercise performance benefits, consume beetroot 2-3 hours before training. For general blood pressure and vascular health, consistent daily intake is more important than timing.
One important note: a single dose of beetroot juice can measurably increase plasma nitrite and lower blood pressure, but the most significant benefits in research come from sustained daily intake over periods of 1-4 weeks. Like most natural interventions, consistency is key.
Comparison
| Factor | Beetroot Juice | Concentrated Shot | Supplement (Capsule/Powder) | Whole Beets |
|---|---|---|---|---|
| Nitrate Dose Consistency | Moderate | High | High (if standardized) | Low (variable) |
| Research Backing | Extensive | Extensive | Moderate | Limited (as sole source) |
| Convenience | Moderate | High | Very High | Low |
| Additional Nutrients | Yes (betalains, potassium, vitamin C) | Some | Minimal | Yes (fiber, folate, minerals) |
| Sugar Content | Moderate (~25g per 500ml) | Low (~5g per shot) | None | Moderate |
| Shelf Life | Short (refrigerate) | Moderate | Long | 1-3 weeks |
| Taste | Earthy (acquired taste) | Intense | None (capsule) / Mild (powder) | Earthy, sweet |
| Cost per Effective Dose | $2-4/day | $2-3/day | $0.50-2/day | $1-2/day |
For most people, a combination approach works well: include whole beets and beetroot juice in your regular diet, and use a concentrated supplement on days when you need reliable, precise dosing — especially before workouts or when dietary intake is inconsistent.
Counterintuitive
Here is one of the most fascinating and counterintuitive findings in nitric oxide research: your antibacterial mouthwash may be sabotaging your beetroot's NO-boosting effects.
Remember that the nitrate-nitrite-NO pathway depends entirely on specific bacteria living on the back of your tongue. These bacteria — species like Veillonella and Actinomyces — are the only way your body can convert dietary nitrate to nitrite. Without them, the chain breaks at the very first step. The nitrates from your beetroot juice get absorbed, circulate through your blood, get concentrated in your saliva, arrive at your tongue, and then... nothing. No bacterial reduction. No nitrite. No nitric oxide.
Antiseptic mouthwashes like chlorhexidine and alcohol-based formulas (Listerine, Scope, and most commercial brands) are designed to kill bacteria indiscriminately. They are extremely effective at this — which is precisely the problem. They wipe out the beneficial nitrate-reducing bacteria along with everything else.
The research on this is striking:
A 2013 study in Free Radical Biology and Medicine found that antibacterial mouthwash completely abolished the blood pressure-lowering effect of dietary nitrate. Participants who consumed beetroot juice after using chlorhexidine mouthwash showed no increase in plasma nitrite levels — the pathway was effectively shut down.
A 2019 study published in Free Radical Biology and Medicine went further, finding that regular antiseptic mouthwash use (twice daily) was independently associated with increased blood pressure and elevated risk of pre-diabetes and diabetes. The researchers hypothesized that chronic disruption of the oral nitrate-nitrite-NO pathway contributed to systemic metabolic dysfunction.
A 2020 study in Scientific Reports confirmed that chlorhexidine mouthwash reduced oral nitrite production by over 90% within just one hour of use, and the effect persisted for at least 12 hours.
The practical takeaway is simple but important: if you are consuming beetroot for its nitric oxide benefits, avoid antiseptic mouthwash. Switch to a non-antibacterial alternative, use saltwater rinses, or simply brush your teeth without mouthwash. Protecting your oral microbiome is not just about dental health — it is a critical component of your cardiovascular system.
This is one of those rare situations in health where doing less is more effective than doing more.
Strategy
Once you understand that your body has two independent pathways for producing nitric oxide, a powerful strategy becomes obvious: activate both of them simultaneously.
Beetroot (dietary nitrate) feeds the nitrate-nitrite-NO pathway. This pathway does not require the eNOS enzyme, works better under low-oxygen conditions, and is especially valuable during exercise and for men whose eNOS activity has declined with age.
L-citrulline feeds the L-arginine/eNOS pathway. L-citrulline converts to L-arginine in the kidneys, which is then used by eNOS to produce nitric oxide directly in the endothelial cells. This pathway is the primary mechanism for moment-to-moment blood flow regulation.
These pathways are not redundant — they are complementary. They operate in different tissues, under different conditions, and through different biochemical mechanisms. When one is impaired (as the eNOS pathway often is with age), the other can partially compensate. When both are well-supplied, the combined NO output is greater than either alone.
Some nitric oxide supplements are formulated to leverage both pathways simultaneously. Nitric Boost Ultra, for example, combines L-citrulline with beetroot extract specifically to activate both the eNOS pathway and the nitrate-nitrite-NO pathway in a single formula. This dual-pathway approach is consistent with the current understanding of NO physiology and represents a more comprehensive strategy than relying on either ingredient alone.
Whether you achieve this through a combination supplement or by pairing dietary beetroot with a standalone L-citrulline supplement, the principle is the same: two pathways are better than one. You can read our full ingredient breakdown here.
Who It Helps
While virtually anyone can benefit from the nitric oxide-boosting effects of dietary nitrate, certain groups stand to gain the most based on the current research.
The exercise performance data is strongest for recreational athletes and people engaged in endurance activities. The 2-3% improvement in time-to-exhaustion, improved oxygen efficiency, and enhanced blood flow to working muscles translate into real-world performance gains. Even weekend warriors and gym regulars benefit from faster recovery and better training quality.
By age 40, most men have lost 20-25% of their peak nitric oxide production. The nitrate-nitrite-NO pathway becomes increasingly important as the eNOS pathway declines. Beetroot provides the precursors for this backup pathway, helping compensate for the enzymatic decline that comes with age. This applies to energy levels, circulation, cognitive sharpness, and sexual health.
The blood pressure research consistently shows the most benefit for individuals with elevated or mildly hypertensive readings. A 3-10 mmHg reduction in systolic pressure can be the difference between a concerning reading and a healthy one. Beetroot is not a replacement for blood pressure medication, but it is a meaningful dietary intervention that works through a well-understood mechanism.
If you experience any of the common signs of low nitric oxide — fatigue, cold extremities, brain fog, declining exercise performance — beetroot addresses the root cause rather than masking symptoms. It provides your body with the raw material it needs to produce more nitric oxide through a pathway that does not depend on aging enzymes.
Common Questions
Beetroot juice begins raising plasma nitrite levels within 1-2 hours of consumption, with peak nitric oxide availability occurring around the 2-3 hour mark. This is why sports scientists recommend consuming beetroot juice 2-3 hours before training or competition. A single dose can measurably lower blood pressure for 6-8 hours. However, the most significant and sustained benefits — particularly for blood pressure and vascular health — come from consistent daily intake over 1-4 weeks. Think of it like exercise: a single session helps, but the real transformation comes from daily consistency.
Beetroot is a food, not a drug, so toxicity is not a realistic concern for most healthy adults. The effective dose used in research is approximately 6.4 mmol of nitrate daily (equivalent to 500 ml of juice or a 70 ml concentrated shot). Consuming significantly more than this does not appear to provide additional nitric oxide benefits — there is a ceiling effect. The most common side effect of high beetroot intake is beeturia, a completely harmless red or pink discoloration of urine and stool caused by betalain pigments. It occurs in about 10-14% of people and has zero health significance. People with calcium oxalate kidney stone history should moderate intake due to beets' oxalate content, and those on blood-thinning medications should consult their doctor.
Cooking reduces nitrate content, but the degree depends on the method. Boiling is the worst offender — up to 50% of the nitrates leach into the cooking water (though you can recapture them by using the water in soups, sauces, or smoothies). Steaming preserves significantly more nitrate, and roasting falls somewhere in between. Raw beetroot and fresh beetroot juice retain the highest nitrate levels. For maximum nitric oxide benefit, raw juice, concentrated shots, or standardized supplements are the most efficient delivery methods. That said, even cooked beets contribute meaningful nitrate — do not let the "perfect" be the enemy of the "good."
Both are effective, and the best choice depends on your priorities. Beetroot juice has the most extensive clinical research behind it and provides additional nutrients (betalains, potassium, vitamin C) beyond just nitrate. However, it has a relatively short shelf life, an earthy taste that not everyone enjoys, and moderate sugar content. Beetroot supplements (capsules or powders) offer standardized nitrate dosing, superior convenience, no sugar, and a long shelf life. Some comprehensive NO supplements like Nitric Boost Ultra combine beetroot extract with L-citrulline to activate both NO pathways simultaneously — something juice alone cannot do. If you enjoy beet juice and want whole-food nutrition, drink the juice. If you want precise dosing and dual-pathway support, a quality supplement may be more practical.
Beetroot is very well tolerated by most people. The most notable side effect is beeturia — red or pink coloration of urine and sometimes stool. This is caused by betalain pigments, is completely harmless, and occurs in about 10-14% of the population. It can be alarming if you are not expecting it, but it has no health significance whatsoever. Some people experience mild digestive discomfort (bloating or gas) when first increasing their beetroot intake, which typically resolves within a few days as the gut adjusts. Beetroot juice contains natural sugars (~25g per 500 ml), which is worth noting if you are managing blood sugar. Beets are moderately high in oxalates, so individuals prone to calcium oxalate kidney stones should consume them in moderation. If you are taking blood pressure medication, talk to your doctor before adding concentrated beetroot to your routine, as the combined effect could lower blood pressure excessively.
The science is clear: beetroot is one of the most effective natural ways to boost nitric oxide production. But getting the full benefit requires the right dose, consistent daily intake, and protecting the oral bacteria that make the pathway work. For men looking to combine beetroot's nitrate pathway with the L-citrulline/eNOS pathway, a well-formulated supplement can activate both systems simultaneously.
Check Nitric Boost Ultra on Official SiteBeetroot extract + L-citrulline dual-pathway formula · 60-day money-back guarantee · Free shipping on 3+ jars