Beetroot Drug, Supplement and Food Interactions: What the Evidence Shows

Beetroot Drug, Supplement and Food Interactions: The Summary

One glass of beetroot juice can nudge blood pressure down, redden your urine and add oxalate to your day. Beetroot drug, supplement and food interactions are therefore worth understanding, yet most remain plausible rather than proven. This page separates what trials have shown from what chemistry only suggests, so you can talk to a clinician with accurate information.

• Blood pressure. A meta-analysis of 16 randomized trials found beetroot juice and inorganic nitrate lowered systolic pressure by about 4.4 mm Hg on average, with no clear effect on diastolic pressure [1]. Additive effects with antihypertensives are plausible, but harm has not been established.
• Mouthwash. Antibacterial mouthwash is the best-documented interaction: it blunts the oral bacteria that activate dietary nitrate [6, 7].
• Nitrate and PDE5 medicines. Prescription nitrates and PDE5 inhibitors have a proven, dangerous interaction with each other [9, 10]. Beetroot's plant nitrate is a different compound, and no study shows the same hazard.
• Oxalate. Beets were among eight foods that raised urinary oxalate in a classic review [15], which matters mainly to people prone to calcium oxalate stones.
• Lab tests. Red urine after beetroot can look like blood, but a urinalysis shows no red blood cells [17].

This article is for education. It is not individual medical advice, and it does not replace your prescriber or pharmacist.

How Beetroot Interactions Are Identified

An interaction is a change in how a drug, nutrient or supplement behaves when taken with another. Researchers identify them in four ways, and each carries a different weight.

1. Human clinical evidence. Randomized trials give beetroot or placebo to people, sometimes while they take a medicine. This is the strongest tier.
2. Observational evidence. Cohort or record-based studies look for patterns in real-world use. They can suggest links but cannot prove cause.
3. Mechanistic evidence. Laboratory, animal or physiology studies show how an effect could occur. Rat data, for example, cannot be assumed to apply to humans.
4. Theoretical concern. Two substances share a pathway, such as vasodilation, so an interaction seems logical, yet nobody has tested it.

Beetroot adds a practical difficulty: dose is inconsistent. Laboratory analysis of 24 juice products found roughly a 50-fold range in nitrate content, and samples of the same product varied by an average of 30% [13]. Another set of commercial tests found nitrate from 2.2 mg to 495.6 mg per serving [14]. A trial result for one product may therefore not transfer to another.

Drug Classes of Concern: Beetroot and Blood Pressure Medication

Beetroot's inorganic nitrate is converted to nitrite and then nitric oxide, a vasodilator [4]. That pathway explains why medicine classes acting on blood vessels are the main focus. Whether each pairing matters clinically differs widely.

Medicine class	Why it is discussed	Evidence type
Antihypertensives (ACE inhibitors, calcium channel blockers, others)	Both lower blood pressure, so effects could add up	Human trial data, no harm shown
Organic nitrates (nitroglycerin, isosorbide)	Both act through nitric oxide and cGMP signalling	Theoretical for beetroot
PDE5 inhibitors (sildenafil, tadalafil)	Both raise cGMP in blood vessels	Theoretical for beetroot
Potassium-raising medicines	Beetroot contains potassium	Theoretical
Antiseptic mouthwash (over the counter)	Kills nitrate-reducing oral bacteria	Human and mechanistic data

Potassium deserves context rather than alarm. Raw beetroot provides roughly 325 mg per 100 g according to USDA-derived values [18], similar to many vegetables. No study reviewed here links beetroot to dangerous potassium levels, so this remains a theoretical point for people with kidney disease or on potassium-sparing medicines.

Specific Documented Interactions

Antiseptic mouthwash

This is the clearest documented example, though the studies tested the nitrate pathway, not beetroot itself. In treated hypertensive adults, three days of antibacterial mouthwash lowered oral nitrate-to-nitrite conversion and raised systolic pressure by 2.3 mm Hg (95% CI 0.5 to 4.0) compared with water [6]. In 19 healthy volunteers, a chlorhexidine mouthwash cut oral nitrite production by 90% and plasma nitrite by 25%, with a blood pressure effect within one day [7]. A rat study found the pressure-lowering effect of nitrate disappeared with mouthwash [8]. Together these suggest antiseptic rinses may weaken beetroot's nitrate effect, although a direct beetroot-plus-mouthwash trial was not found in this review.

Antihypertensive medicines

Evidence here is mixed and does not show harm. A British Heart Foundation-funded trial gave 250 ml of beetroot juice or placebo to 64 adults; about half were taking antihypertensives yet had not reached target, and blood pressure fell by roughly 8/4 mm Hg [3]. The trial was small, as the release itself acknowledged. A separate randomized trial in treated hypertensive individuals reported no effect of beetroot juice on blood pressure [4]. Neither source reports a dangerous drop in pressure, but neither was designed to detect rare events. A 2022 systematic review of randomized trials in adults with hypertension also examined this question [2].

Organic nitrates with PDE5 inhibitors

This interaction is real but involves prescription drugs, not beetroot. Sildenafil increased the blood pressure-lowering effect of glyceryl trinitrate in a placebo-controlled crossover study, and the authors judged the combination contraindicated [9]. Nitroglycerin labelling carries the same contraindication [10], and UK guidance lists waiting periods of 24 hours after sildenafil and 48 hours after tadalafil before nitrates [12]. One observational analysis of co-prescription found no significant link with adverse cardiovascular events (odds ratio 0.58, 95% CI 0.28 to 1.13), yet the contraindication stands [11]. No source here tested beetroot with PDE5 inhibitors.

Theoretical and Mechanistic Interactions

The items below are reasoned from how beetroot works. None has been confirmed as a harmful interaction in the sources reviewed, so they should be read as questions for a clinician, not as findings.

• Additive blood pressure lowering. A meta-regression found larger daily nitrate doses were associated with larger systolic reductions [1]. In principle, a high-nitrate product plus several antihypertensives could lower pressure more than expected in someone already close to their target. This has not been demonstrated.
• Effects beyond nitrate. One meta-analysis argued beetroot juice may lower pressure through nitrate-independent routes too [5]. That makes any prediction based on nitrate content alone less certain.
• Shared nitric oxide signalling. Organic nitrates, PDE5 inhibitors and beetroot all act on the nitric oxide and cGMP pathway [9]. Beetroot nitrate must first be converted to nitrite, and its average effect on pressure is modest [1]. Whether it adds to these drugs is unknown.
• Potassium load. Possible relevance exists for people with reduced kidney function or potassium-sparing medicines, as noted above [18].
• Other products affecting oral bacteria. Because mouthwash disrupts nitrate activation [7], other agents that alter oral bacteria could plausibly do likewise. These have not been tested with beetroot.

Supplement-Supplement Interactions

Human studies pairing beetroot with other supplements are scarce, so most of this section is reasoning from related evidence.

• Vitamin C. A cross-sectional analysis of stone-forming and non-stone-forming adults cites earlier work reporting that 1,000 mg of vitamin C twice daily raised urinary oxalate by 22% [16]. Because beetroot also contributes oxalate [15], combining high-dose vitamin C with large beetroot intakes is a theoretical concern for stone-prone people. Direct testing was not found.
• Calcium. Dietary calcium can bind oxalate in the gut and reduce its absorption [15]. This is a possible protective pairing when calcium is taken with meals, not a proven treatment.
• Other nitric oxide boosters. Supplements marketed to raise nitric oxide, including arginine, citrulline and other nitrate-rich plant extracts, share beetroot's goal. Additive blood vessel effects are plausible, yet no study retrieved here has tested them together with beetroot.
• Multi-ingredient blends. Nitrate content is rarely labelled and varies widely [13, 14], so the total nitrate in a stack of products is hard to estimate.

Food Interactions and Kidney Stone Risk from Oxalate

Food interactions with beetroot centre on oxalate, calcium and nitrate.

Oxalate and stones. About 80% of kidney stones contain calcium, and most of those are mainly calcium oxalate [16]. A review of dietary oxalate named beets among only eight foods that significantly raised urinary oxalate in volunteers, though the rise was not proportional to each food's oxalate content [15]. The same review noted that risk is greatest in people who absorb oxalate efficiently. This is human evidence, but it comes from an older review of small feeding studies, and it did not test modern concentrated beetroot juices or powders.

Calcium. Restricting dietary calcium increased oxalate absorption and excretion, while higher calcium intake may lower urinary oxalate by binding oxalate in the gut [15]. For people with a stone history, that is why calcium-containing meals and urine testing, not blanket avoidance, are the usual discussion points with a clinician.

Other nitrate-rich vegetables. Beetroot is not the only source of inorganic nitrate; lettuce and cabbage also contain high levels [3]. Eating several nitrate-rich foods plus a concentrated beetroot product could add up, but no study here measured that combined effect.

Eating beetroot as a vegetable is a lower-concern situation than daily concentrated products, although no study here compared the two directly. The picture changes when juices, powders or shots deliver a concentrated dose every day.

Lab-Test Interference: Beeturia and Urine Colour

The one well-described interference is visual rather than chemical. Beeturia is pink to deep red urine after eating beetroot, reported in about 10% to 14% of people and more often in those with iron deficiency or malabsorption [17]. Pigments called betacyanins cause the colour.

Beeturia can be mistaken for blood in the urine. In beeturia, microscopic urinalysis finds no red blood cells even though the colour persists [17]. A clinician may still consider iron status when beeturia is frequent, since the same source links it with iron-absorption problems [17].

What the evidence does not cover matters too. No study retrieved for this article showed that beetroot alters routine blood chemistry, kidney function tests or stool-based bleeding tests, so any such effect is unestablished. Anyone with red urine or stools that is unexplained, painful or persistent should not assume beetroot is the cause, and should mention recent beetroot intake when seeking care.

Severity and Strength of Evidence

No beetroot interaction reviewed here has strong, direct evidence of serious harm. The table rates each item by evidence type and by the likely size of the consequence if it were real.

Potential interaction	Evidence type	Strength of evidence	Possible consequence	Sources
Antiseptic mouthwash weakens nitrate effect	Human trials of mouthwash alone; animal and mechanistic data	Moderate for the pathway; no direct beetroot trial found	Small blood pressure rise (about 2.3 mm Hg systolic)	[6, 7, 8]
Beetroot with antihypertensive medicines	Small human trials, mixed results	Low to moderate; no harm shown	Additive pressure lowering is theoretical	[3, 4]
Beetroot with organic nitrates or PDE5 inhibitors	Documented for the drug pair; theoretical for beetroot	Strong for the drugs, none for beetroot	Severe hypotension for the drug pair; unknown for beetroot	[9, 10, 12]
Beetroot oxalate and stone formation	Older human feeding data	Low to moderate	Higher urinary oxalate; stone outcomes not tested	[15, 16]
Vitamin C plus beetroot oxalate	Theoretical, from related data	Very low	Possible higher urinary oxalate	[15, 16]
Potassium with kidney disease or potassium-sparing drugs	Theoretical	Very low	Unknown	[18]
Red urine mistaken for blood	Clinical description	High that it occurs	Low; mainly confusion and worry	[17]

Who Should Consult a Healthcare Professional

These groups have a plausible reason to raise concentrated beetroot juice, powder or shots with a clinician or pharmacist first. Casual use of beetroot as food is a lower-concern situation.

• People taking blood pressure medicines or other medicines that act on blood vessels, including prescription nitrates and PDE5 inhibitors.
• People with low blood pressure or a history of fainting, because beetroot lowers systolic pressure on average [1].
• People with a history of kidney stones, high urinary oxalate or reduced kidney function [15, 16].
• People on potassium-sparing medicines or with kidney disease, where potassium intake is usually monitored [18].
• People who use antiseptic mouthwash daily and are taking beetroot for its blood pressure effect [6, 7].
• Anyone with persistent or unexplained red urine or stools, who should not assume beetroot is the cause [17].

Practical precautions

1. Check the label for nitrate content; it is often missing and varies enormously between products [13, 14].
2. Tell your prescriber and pharmacist about any beetroot supplement, as you would any herbal product.
3. Do not stop or change prescribed medicine on your own because of beetroot.
4. If you monitor blood pressure at home, share the readings when you start a concentrated product.
5. Contact a clinician promptly for dizziness, fainting or palpitations after starting, and seek emergency help for chest pain.

This is general information, not a recommendation for any individual.

Frequently Asked Questions About Beetroot Interactions

Can I take beetroot juice with blood pressure medicine?

Small trials, some including people on antihypertensives, did not report harm in the sources reviewed, and one found no effect in treated hypertension [3, 4]. Additive lowering is plausible, so ask your prescriber before using a concentrated product daily.

Is beetroot nitrate the same as the nitrate in heart medicines?

No. Beetroot supplies inorganic nitrate that the body converts to nitrite and then nitric oxide [4]. Heart medicines such as nitroglycerin are organic nitrates with their own labelled PDE5 contraindication [10]. No study here tested beetroot with PDE5 inhibitors, so follow your medicine's guidance.

Does mouthwash cancel beetroot's effect?

It may reduce it. Antibacterial mouthwash blunted oral nitrate conversion and raised blood pressure slightly in human studies [6, 7], but a direct beetroot trial was not found.

Does beetroot cause kidney stones?

This has not been shown. Beets can raise urinary oxalate [15], which matters for people prone to calcium oxalate stones, but stone outcomes were not measured.

Why is my urine red after eating beets?

Beeturia affects roughly 10% to 14% of people and is usually harmless, though it is more frequent with iron deficiency [17]. Seek advice if it persists or you are unsure.

Conclusion: What Is Known and What Is Not

Known: beetroot juice lowers systolic pressure modestly [1], antiseptic mouthwash can interfere with the pathway [6, 7], beets raise urinary oxalate in volunteers [15], and beeturia is common [17]. Uncertain: whether beetroot meaningfully adds to antihypertensives, nitrates or PDE5 inhibitors, and whether concentrated products affect stone risk. Many theoretical concerns here lack direct testing, and product doses vary widely [13, 14].

Bring your medicine list, any beetroot product label and your home blood pressure readings to your next appointment, and ask your clinician or pharmacist whether concentrated beetroot suits your situation.

References

All sources were opened or returned in search on 13 October 2026. Where a source page did not show a journal year or full author list, none is given here rather than guessed.

1. Inorganic nitrate and beetroot juice supplementation reduces blood pressure in adults: a systematic review and meta-analysis (authors include Siervo M and Mathers JC). PubMed-indexed record; Newcastle University record.
2. Benjamim CJR, Porto AA, Valenti VE, et al. Nitrate derived from beetroot juice lowers blood pressure in patients with arterial hypertension: a systematic review and meta-analysis. Front Nutr. 2022. doi:10.3389/fnut.2022.823039.
3. Queen Mary University of London. Daily beetroot juice lowers blood pressure, scientists find (news release on the trial published in Hypertension). qmul.ac.uk.
4. Dietary nitrate from beetroot juice for hypertension: a systematic review. Biomolecules. PMC6316347; reference list at MDPI.
5. The nitrate-independent blood pressure-lowering effect of beetroot juice: a systematic review and meta-analysis. PMC5683004.
6. Bondonno C, et al. Antibacterial mouthwash blunts oral nitrate reduction and increases blood pressure in treated hypertensive men and women. Flinders University record.
7. Physiological role for nitrate-reducing oral bacteria in blood pressure control. PMC3605573.
8. Petersson J, Carlstrom M, Schreiber O, et al. Gastroprotective and blood pressure lowering effects of dietary nitrate are abolished by an antiseptic mouthwash. Free Radic Biol Med. 2009;46(8):1068-1075. doi:10.1016/j.freeradbiomed.2009.01.011; PubMed 19439233.
9. Sildenafil citrate and blood-pressure-lowering drugs: results of drug interaction studies with an organic nitrate and a calcium antagonist. PubMed 10078539.
10. Nitroglycerin tablet prescribing information, contraindications and drug interactions (PDE-5 inhibitors). Medlibrary label copy.
11. Nitrate and PDE5 inhibitor concomitant use does not appear to be associated with adverse CV events (summary of a co-prescription study). Hospital Pharmacy Europe.
12. Nitrates and phosphodiesterase inhibitors (UK guidance summary). Primary Care Notebook.
13. Gallardo EJ, Coggan AR. What is in your beet juice? Nitrate and nitrite content of beet juice products marketed to athletes. Int J Sport Nutr Exerc Metab. 2019. doi:10.1123/ijsnem.2018-0223.
14. ConsumerLab. Tests of beetroot and nitrate products (press release, 9 December 2025). Commercial testing, not peer reviewed. consumerlab.com.
15. Effect of dietary oxalate and calcium on urinary oxalate and risk of formation of calcium oxalate kidney stones. J Am Diet Assoc. PubMed 8335871.
16. Determinants of 24-hour urinary oxalate excretion. PMC2518810.
17. Beeturia. StatPearls. NCBI Bookshelf NBK537012.
18. Potassium in beetroot, USDA-derived values. FoodStruct.