Beetroot Powder Side Effects: Facts vs. Myth

Free Tool · 7-Day Race Blueprint: Generate your personalized peak-week plan, complete with a branded PDF covering your daily calorie targets, 7-day nitrate loading and carb-load math, and an intra-race fuel menu calibrated to your body weight. Built from the research of Dr. Asker Jeukendrup, Dr. Andrew Jones, and the AIS Sports Supplement Framework.

Most athletes do their homework before adding a new supplement. If you searched "beetroot side effects" before buying, good: you are asking exactly the right questions. Here is the honest breakdown of what is real, what is form-dependent, and what disappears entirely when you choose a standardized extract over raw beet powder or juice.

Side effect	Frequency	Mechanism	Prevention
Beeturia (pink urine/stool)	~10-14% of population	Betalain pigment; genetic inability to break down	Harmless; no action needed
Digestive upset	~5-8% at acute doses	High oxalate content; rapid fermentation	Take with food; start at half dose
Temporary blood pressure drop	Possible at high doses	Nitric oxide vasodilation	Avoid >12 mmol single dose; caution with BP medication
Mouthwash interference	100% if used	CPC/chlorhexidine eliminates oral bacteria	Avoid antibacterial mouthwash on race day
Purple-stained teeth/tongue	Rare	Betalain pigment	Rinse mouth after taking
Loose stools	Rare, high doses	Oxalate load + osmotic effect	Reduce dose; avoid raw beet fiber forms

Side Effect 1: Beeturia (Pink or Red Urine and Stool)

Beeturia, the pink or red discoloration of urine and sometimes stool after eating beets, affects roughly 10 to 15 percent of people and is completely harmless. It is caused by betalain pigment passing through digestion partially intact, not by any kidney or digestive dysfunction. Standardized extract produces far less visible staining than raw beet powder or juice because the extraction process reduces pigment load while concentrating nitrate.

Beeturia is the pink or red discoloration of urine and stool that follows beet consumption. Roughly 10 to 15 percent of people experience it after eating whole beets or drinking beet juice. It is caused by betalain pigments, the same compounds responsible for beets' deep crimson color, passing through the digestive system partially intact and being excreted through the kidneys and colon.

Why do some people get it and others do not? Genetics. A subset of the population has reduced capacity to metabolize betalains in the gut. In those individuals, more pigment passes into circulation and ultimately into urine. This is not a sign of damage or abnormal kidney function. Iron-deficiency anemia can also increase betalain absorption, so beeturia sometimes prompts athletes with undiagnosed low iron to check their levels, which is actually useful information.

The practical relevance for supplement users: standardized beetroot extract produces far less visible staining than whole-root powder or juice. The extraction process concentrates dietary nitrates while reducing the betalain pigment load. If you have experienced alarming pink urine after beet juice shots, switching to a quality extract often resolves it. If you do notice mild coloration, no action is required.

Side Effect 2: GI Distress (Bloating, Cramping, Urgency)

GI distress from beet supplements is a fiber problem, not a nitrate problem. Raw beet powder and juice carry the whole root's insoluble fiber, and at race intensity, blood flow to the gut drops sharply, so undigested fiber ferments and triggers bloating, cramping, and urgency. Beetroot Pro's standardized extract removes that fiber and the natural sugar during processing, delivering a fiber-free, 0-gram-sugar nitrate dose so the GI liability disappears while the performance benefit stays intact.

GI distress is the most common complaint from athletes who use raw beet powder or high-volume beet juice. The culprit is fiber. Whole-root beet products carry substantial insoluble and soluble fiber. Under normal circumstances, dietary fiber is beneficial. During high-intensity exercise, it is not. Blood flow is redirected away from the gut, digestion slows, and undigested fiber ferments in the colon, producing gas and cramping. In worst-case scenarios, urgency becomes a race-day disaster.

Timing compounds the problem. Consuming raw powder or beet juice 30 minutes before exercise gives fiber almost no time to clear the stomach. Athletes who experience GI distress after beet products and push intake earlier, to 90 or 120 minutes pre-event, often see partial improvement, but the fiber load remains.

Standardized extraction removes the fiber during processing. The result is a concentrated nitrate dose without the bulk that triggers GI symptoms. This is one of the primary reasons extract is the race-day choice for elite endurance athletes rather than whole-root juice: you get the nitric oxide performance benefit without the gastrointestinal liability. For the full mechanism behind why fiber, not nitrate, is the trigger, see our breakdown of why beet supplements cause GI distress.

If you have abandoned beet supplements because of GI issues after juice or raw powder, extract is worth re-evaluating before writing off the category entirely.

Side Effect 3: Oxalate Load

Beets rank among the higher-oxalate vegetables, and daily nitrate-loading protocols with raw powder or juice can mean meaningful chronic oxalate intake, a real concern for anyone with a history of calcium oxalate kidney stones. Standardized extraction concentrates dietary nitrate from the beet matrix while removing much of the oxalate, so the same 300 to 600 mg clinical nitrate dose arrives with a far smaller oxalate load.

Beets are among the higher-oxalate vegetables. Oxalates are naturally occurring compounds found in many plant foods. For most people, dietary oxalate is absorbed, excreted by the kidneys, and causes no problems. For a subset of individuals, specifically those with a personal or family history of calcium oxalate kidney stones, chronic high oxalate intake can contribute to stone formation.

Athletes on daily nitrate-loading protocols who use raw beet powder or juice consume substantial oxalate over time. A clinical loading protocol might involve 500 to 600 mg of inorganic nitrate per day for several days, which, from a whole-beet source, comes packaged with meaningful oxalate content. See our guide on how much nitrate is in your beet supplement for how that dose is actually measured and verified on a label.

Standardized extraction concentrates inorganic nitrate from the beet matrix while removing much of the oxalate. For athletes who load frequently or use beetroot supplementation year-round, extract is the lower-risk long-term choice, particularly for those with any history of kidney stones (Hord NG et al., 2009).

If you have had a kidney stone previously, especially a calcium oxalate stone, consult a physician or registered dietitian before starting any high-dose beet supplement protocol regardless of the form.

Side Effect 4: The Mouthwash Interaction (Not a Side Effect, a Mechanism Killer)

Antibacterial mouthwash is the single most common reason beet supplements fail to work. The nitrate-to-nitric-oxide pathway depends entirely on oral bacteria to convert swallowed nitrate to nitrite, and chlorhexidine or CPC-based rinses eliminate those bacteria, blocking the conversion almost completely. Skipping antibacterial mouthwash on training and race days is a free fix with no downside.

This is not a side effect in the traditional sense, but it deserves prominent placement because it affects so many athletes. The nitrate-to-nitric-oxide conversion pathway depends on oral bacteria. Dietary nitrate is absorbed in the small intestine and circulated to the salivary glands. Bacteria on the tongue reduce salivary nitrate to nitrite. That nitrite is swallowed and converted to nitric oxide in the stomach, particularly in the acidic gastric environment.

Antibacterial mouthwash eliminates the oral bacteria that make this conversion possible. Studies show that antiseptic mouthwash use before beet supplementation can completely block the blood pressure and performance effects of dietary nitrate (Larsen FJ et al., 2007).

If you use mouthwash in the morning and take your beetroot supplement shortly after, you may be getting little to no performance benefit. Skip the antibacterial mouthwash on training and race days, or use it at night only. Plain water rinsing is fine. See our dedicated guide on the mouthwash mistake that kills your beet dose for the full mechanism and protocol recommendations.

Side Effect 5: Nitrate Interactions with Certain Medications

Dietary nitrate supplements should not be combined with PDE-5 inhibitors (sildenafil, tadalafil) or prescription nitrate medications for angina (nitroglycerin, isosorbide dinitrate), since both work through the same cGMP vasodilation pathway and stacking them can cause a dangerous drop in blood pressure. This is rare in competitive endurance athletes but more relevant for Masters athletes aged 50 and older managing cardiovascular conditions.

Dietary nitrate supplements should not be combined with certain prescription medications. The two categories to know:

PDE-5 inhibitors: Sildenafil (Viagra), tadalafil (Cialis), and related drugs work by inhibiting the phosphodiesterase enzyme that breaks down cyclic GMP. Nitric oxide also works through the cGMP pathway. The combined effect of a PDE-5 inhibitor and high dietary nitrate can produce an additive vasodilation response that causes a significant and potentially dangerous drop in blood pressure.

Nitrate-based angina medications: Nitroglycerin and isosorbide dinitrate are prescription nitrate medications used to treat angina and heart failure. Combining supplemental dietary nitrate with these drugs can result in excessive vasodilation.

The realistic risk in the endurance athlete population is low. Most competitive cyclists, runners, and triathletes are not on these medications. The concern is more relevant for Masters athletes (50 plus) who may have cardiovascular conditions managed with prescription nitrates or who use PDE-5 inhibitors. If you are on any cardiovascular medication, review your supplement stack with your prescribing physician before adding dietary nitrate.

Side Effect 6: Blood Pressure Drop (Relevant for Hypotensive Individuals)

Dietary nitrate lowers systolic blood pressure by roughly 4 to 5 mmHg on average through nitric oxide-driven vasodilation, a benefit for normotensive and hypertensive individuals. For people with already-low baseline blood pressure, that same drop can cause lightheadedness or orthostatic hypotension, especially standing up right after exercise, so starting with a lower dose and monitoring symptoms is the practical safeguard.

The nitric oxide pathway lowers blood pressure by dilating blood vessels. This is largely the point: improved vasodilation means better oxygen delivery to working muscles. For normotensive and hypertensive individuals, this effect is beneficial or neutral (Bailey SJ et al., 2009).

For people with already-low blood pressure (clinical hypotension), the additional vasodilation from dietary nitrate supplementation can cause lightheadedness, dizziness, or orthostatic hypotension, the sensation of feeling faint when standing up quickly. This can be more pronounced immediately post-exercise, when blood is pooled in the lower extremities.

If you are prone to low blood pressure or regularly experience lightheadedness when standing, start with a lower dose and monitor how you feel. Most athletes do not have this issue. For the flip side of this same nitric oxide pathway, the cardiovascular and vascular blood flow benefits it provides, see beetroot benefits for men.

The Form Matters More Than the Dose

Raw beet powder and beet juice share the same GI distress and oxalate risks because both carry the whole root's fiber and pigment load. Standardized extract, including Beetroot Pro's fiber-free, 0-gram-sugar formulation, removes that load during processing while keeping the mechanism-based effects (mouthwash interaction, medication interactions, blood pressure response) identical across all forms, since those come from nitrate chemistry itself, not the plant matrix.

A summary of how different beetroot forms compare across the side effects covered above:

Side Effect	Raw Beet Powder	Beet Juice	Standardized Extract
Beeturia (pink urine)	High frequency	High frequency	Low to minimal
GI distress (bloating, cramping)	Common, especially near exercise	Common	Rare
Oxalate load (daily use)	Significant	Significant	Low
Mouthwash interaction	Affects all forms equally	Affects all forms equally	Affects all forms equally
Medication interactions	Affects all forms equally	Affects all forms equally	Affects all forms equally
Blood pressure drop	Present	Present	Present (same mechanism)

The pattern is clear: the side effects athletes most commonly worry about, GI distress and oxalate load, are properties of the whole-food matrix, not of dietary nitrate itself. Standardized extraction addresses them at the processing level. The mechanism-based effects (mouthwash interaction, medication interactions, blood pressure response) are inherent to nitrate chemistry and apply equally across all forms.

Bottom Line

Beetroot supplementation is safe and well-tolerated for the vast majority of endurance athletes. Reported side effects split into two groups: form-dependent issues (GI distress, oxalate load, heavy beeturia) that come from the whole-beet fiber and pigment matrix and are largely resolved by switching to a standardized, fiber-free extract like Beetroot Pro, and mechanism-based watchpoints (mouthwash timing, medication interactions, blood pressure response) that apply equally regardless of form.

Beetroot supplementation is safe and well-tolerated for the vast majority of endurance athletes. The reported side effects cluster into two groups:

Form-dependent issues (resolved by choosing extract): GI distress, oxalate load, and heavy beeturia are primarily associated with raw whole-beet products and high-volume juice. Standardized extract eliminates most of these through processing.

Real watchpoints for a small subset: The mouthwash interaction affects athletes of all beetroot product types. Medication interactions matter for anyone on PDE-5 inhibitors or prescription nitrates. Blood pressure drop is worth monitoring for hypotensive individuals.

If raw beet powder or juice has given you problems in the past, those experiences were real, but they may not predict your response to a standardized extract. The nitrate science is robust. The form you use determines most of what you actually feel.

---

Frequently Asked Questions

The most common beetroot supplement questions center on daily-use safety, stomach upset, blood pressure limits, and medication interactions, all of which come down to two variables: the form of beet product used and any pre-existing medical condition.

Is beetroot powder safe for daily use?

Yes, for most athletes. The key variable is form. Standardized extract used in daily loading protocols carries minimal oxalate load and low GI risk. Raw whole-beet powder consumed daily in performance doses is harder on the digestive system and carries a higher oxalate burden over time. If you have a history of kidney stones, consult a physician regardless of form.

Is beet juice bad for your kidneys?

Not for most people, in normal amounts. Beets are a higher-oxalate food, and beet juice concentrates that oxalate load in liquid form, so daily high-dose juice protocols are the scenario worth caring about, not occasional use. The concern is specific to anyone with a personal or family history of calcium oxalate kidney stones, where chronic high oxalate intake is a contributing factor. Standardized extract concentrates the dietary nitrate while removing much of the oxalate, so it carries a meaningfully lower kidney-stone-relevant load than raw juice at an equivalent nitrate dose (Hord NG et al., 2009). If you have had a calcium oxalate kidney stone, talk to a physician before starting a daily beet juice or beet powder protocol.

Can beet juice make your urine red?

Yes, and it is harmless. Beeturia, the pink or red discoloration of urine and sometimes stool, affects roughly 10 to 15 percent of people after drinking beet juice or eating whole beets. It is caused by betalain pigment, the same compound responsible for beets' deep color, passing through digestion partially intact rather than being fully broken down. It is not blood and does not indicate kidney or digestive dysfunction, genetics determine who experiences it. Juice and raw whole-beet powder produce the most visible staining since they carry the full pigment load of the root; a standardized extract produces far less because the extraction process reduces pigment while concentrating nitrate.

Why does beetroot give me an upset stomach?

The most likely cause is fiber content. Raw beet powder and beet juice both contain the full fiber matrix of the root, which is difficult to digest during exercise when blood flow to the gut is reduced. Timing matters too: taking a high-fiber beet product 30 minutes before a race is far worse than 2 hours before. Switching to a standardized extract, which removes fiber during processing, resolves GI symptoms for most athletes.

Can beetroot powder lower blood pressure too much?

For normotensive and hypertensive individuals, the blood pressure reduction from dietary nitrate is modest and beneficial. Clinical research shows average reductions of around 4 to 5 mmHg systolic. For someone with already-low baseline blood pressure, this can occasionally cause lightheadedness, particularly when standing up after exercise. If you have hypotension or take blood pressure medications, start with a lower dose and monitor your response.

Does beetroot interact with any supplements or medications?

The most clinically significant interactions are with PDE-5 inhibitors (sildenafil, tadalafil) and prescription nitrate medications used for angina, where the combined vasodilation effect can cause excessive blood pressure reduction. For most endurance athletes, these are not relevant. Always review your full supplement and medication list with a physician if you have a cardiovascular condition. The mouthwash interaction is also worth noting: antibacterial mouthwash used before supplementation blocks the oral bacteria needed for nitrate conversion and can negate the performance benefit entirely.

---

References: Larsen FJ, Ekblom B, Sahlin K, Lundberg JO, Weitzberg E. Effects of dietary nitrate on blood pressure in healthy volunteers. N Engl J Med. 2006;355(26):2792-3. / Hord NG, Tang Y, Bryan NS. Food sources of nitrates and nitrites: the physiologic context for potential health benefits. Am J Clin Nutr. 2009;90(1):1-10. / Bailey SJ, Winyard P, Vanhatalo A, Blackwell JR, DiMenna FJ, Wilkerson DP, Tarr J, Benjamin N, Jones AM. Dietary nitrate supplementation reduces the O2 cost of low-intensity exercise and enhances tolerance to high-intensity exercise in humans. J Appl Physiol. 2009;107(4):1144-55.

---

These statements have not been evaluated by the Food and Drug Administration. This product is not intended to diagnose, treat, cure, or prevent any disease. This content is for informational purposes only and does not constitute medical advice. Consult a qualified healthcare professional before starting any supplement program.