Beetroot extract has become increasingly popular as a nutritional supplement in the UK, valued primarily for its high dietary nitrate content. Many people wonder how many milligrams of beetroot extract they should take to potentially support cardiovascular health or exercise performance. Whilst there is no official recommended daily allowance established by UK regulatory bodies, research studies typically use doses providing approximately 5–9 mmol of dietary nitrates daily (roughly 310–560 mg of nitrate). However, the appropriate dosage varies considerably depending on the supplement's formulation, your individual health status, and your intended purpose. This article examines the evidence-based guidance on beetroot extract dosing, safety considerations, and when to seek professional medical advice.

What Is Beetroot Extract and How Does It Work?

Beetroot extract is a concentrated supplement derived from Beta vulgaris, the common beetroot vegetable. It is available in various forms including capsules, tablets, powders, and liquid extracts, and has gained popularity as a nutritional supplement in the UK and internationally. The extract contains several bioactive compounds, most notably dietary nitrates, betalains (pigments with antioxidant properties), and various vitamins and minerals.

The primary mechanism of action centres on the high nitrate content found in beetroot. When consumed, dietary nitrates are converted by bacteria in the mouth into nitrite, which is then further converted in the body to nitric oxide (NO). Nitric oxide is a crucial signalling molecule that promotes vasodilation—the widening of blood vessels—which may help improve blood flow and reduce blood pressure. This process is known as the nitrate-nitrite-nitric oxide pathway.

Beyond cardiovascular effects, beetroot extract contains betalains, which possess antioxidant and anti-inflammatory properties. These compounds may help protect cells from oxidative stress, though the clinical significance of these effects requires further research. Some studies have investigated beetroot extract for exercise performance, cognitive function, and general wellbeing, though evidence for non-cardiovascular benefits remains inconclusive.

It is important to note that beetroot extract is classified as a food supplement in the UK, regulated by the Food Standards Agency (FSA) and local authorities. As a food supplement, it is not subject to the same rigorous testing and approval processes as pharmaceutical products. Under GB Nutrition and Health Claims regulations, supplements cannot make claims about preventing or treating diseases. Consumers should approach health claims with appropriate caution and seek evidence-based information from reliable sources such as the NHS or British Heart Foundation.

Recommended Beetroot Extract Dosage in the UK

There is currently no official recommended daily allowance (RDA) or standardised dosage for beetroot extract established by UK regulatory bodies such as NICE, the NHS, or the MHRA. Dosage recommendations vary considerably depending on the form of the supplement, the concentration of active ingredients (particularly nitrates), and the intended purpose.

Research studies have typically used doses providing approximately 5-9 mmol of dietary nitrates per day (equivalent to about 310-560 mg of nitrate, as 1 mmol nitrate ≈ 62 mg). This roughly equates to 500 ml of beetroot juice, though nitrate content can vary significantly between products and juice preparations.

When selecting beetroot extract supplements, it's important to focus on the nitrate content rather than just the total extract amount. Most commercially available beetroot extract supplements in the UK list the total extract weight (often 500-3,000 mg per serving), but the actual nitrate content—the key active component—can vary significantly.

Research studies examining potential effects have used:

• Doses containing approximately 5-9 mmol nitrate daily (310-560 mg) for studies investigating cardiovascular parameters

• Acute doses (taken 2-3 hours before exercise) for studies examining exercise performance

It is essential to check the product label for specific guidance, as manufacturers provide dosing instructions based on their particular formulation. Some products are standardised to contain a specific percentage of nitrates or betalains, whilst others simply list the total beetroot extract content. When comparing products, look for those that clearly state the nitrate content per serving.

The European Food Safety Authority (EFSA) has established an Acceptable Daily Intake (ADI) for nitrate of 3.7 mg per kg of body weight per day. For safety, it's advisable not to exceed this intake from all sources (food and supplements) without clinical oversight. Always start with the lowest recommended dose and follow the manufacturer's instructions.

Factors That Affect Your Beetroot Extract Dosage

Several individual and clinical factors may influence the appropriate dosage of beetroot extract for any given person. Understanding these variables can help you make informed decisions about supplementation.

Body weight and size may play a role in determining optimal dosage, as with many supplements and medications. Larger individuals may require higher doses to achieve similar physiological effects, though specific weight-based dosing guidelines for beetroot extract have not been established in clinical research.

Baseline blood pressure is particularly relevant for those taking beetroot extract for cardiovascular purposes. Individuals with normal or low blood pressure may experience more pronounced effects from nitrate supplementation compared to those with significantly elevated blood pressure. Those with hypotension should exercise particular caution, as beetroot extract may further lower blood pressure.

Dietary nitrate intake from food sources should be considered. If you regularly consume nitrate-rich vegetables such as spinach, rocket, lettuce, and beetroot itself, your total nitrate intake will be higher. The cumulative effect may mean that lower supplement doses are appropriate. Conversely, those with limited vegetable intake may benefit from higher supplementation.

Medication interactions can significantly affect appropriate dosing. Beetroot extract may interact with medications for blood pressure, nitrate medicines for angina (such as glyceryl trinitrate or isosorbide), and PDE5 inhibitors for erectile dysfunction due to additive blood pressure-lowering effects. Evidence for interactions with anticoagulant or antiplatelet medications is limited.

Oral hygiene products can affect efficacy. Antibacterial mouthwash and recent antibiotic use may reduce the effectiveness of beetroot extract by disrupting the oral bacteria needed to convert nitrate to nitrite, the first step in the pathway to nitric oxide production.

Intended purpose influences dosage requirements. Research suggests that acute doses (taken 2–3 hours before activity) may be more appropriate for exercise performance, whilst lower, sustained daily doses may be preferable for long-term cardiovascular studies. The timing and pattern of supplementation should align with your specific health goals.

Individual response varies considerably between people. Some individuals are "non-responders" to dietary nitrates, possibly due to differences in oral bacteria composition or genetic factors affecting nitric oxide metabolism. If you do not notice any effects after several weeks of consistent use at recommended doses, increasing the dose may not necessarily be beneficial.

Kidney function is important to consider, particularly with beetroot juice or powder forms, which may contain significant potassium. Those with chronic kidney disease or on potassium-restricted diets should seek advice from their renal team or dietitian before using beetroot supplements.

Potential Side Effects and Safety Considerations

Beetroot extract is generally considered safe for most people when taken at recommended doses, though several side effects and safety considerations warrant attention.

Common, benign side effects include beeturia—the harmless pink or red discolouration of urine and sometimes stools. This occurs in approximately 10–14% of the population and is caused by betalain pigments. Whilst alarming in appearance, beeturia is not medically concerning and resolves when supplementation is discontinued. Some individuals may also experience a temporary change in the colour of their tongue. If discolouration is accompanied by pain, blood clots, black tarry stools, or persists after stopping beetroot, seek medical advice.

Gastrointestinal symptoms can occur, particularly at higher doses or when first starting supplementation. These may include:

• Mild stomach upset or discomfort

• Bloating or gas

• Diarrhoea (usually with very high doses)

• Nausea

These effects are typically mild and often resolve with continued use or dose reduction. Taking beetroot extract with food may help minimise gastrointestinal discomfort.

Vasodilatory effects may include headache or flushing in some individuals, particularly at higher doses, due to the nitric oxide-mediated widening of blood vessels.

Blood pressure effects represent the most clinically significant consideration. Because beetroot extract can lower blood pressure, individuals with hypotension or those taking antihypertensive medications should exercise caution. Excessive blood pressure reduction may cause dizziness, light-headedness, or fainting. Regular blood pressure monitoring is advisable if you have cardiovascular conditions.

Kidney stone risk is a theoretical concern, as beetroot is high in oxalates—compounds that can contribute to calcium oxalate kidney stone formation in susceptible individuals. Those with a history of kidney stones should consult their GP before taking beetroot extract supplements, though there is no definitive evidence linking beetroot supplementation to increased stone formation.

Contraindications include individuals taking nitrate medications for angina (such as glyceryl trinitrate or isosorbide mononitrate), as the combination may cause dangerous drops in blood pressure. Beetroot extract should also be used cautiously with PDE5 inhibitors for erectile dysfunction due to potential additive blood pressure-lowering effects.

Pregnant and breastfeeding women should consult their healthcare provider before taking beetroot extract supplements, as safety data in these populations is insufficient, despite beetroot as a food being considered safe.

If you experience any suspected adverse reactions to beetroot supplements, you can report them through the MHRA Yellow Card Scheme (website or app).

When to Speak to Your GP About Beetroot Supplements

Whilst beetroot extract is available without prescription, several circumstances warrant discussion with your GP or another qualified healthcare professional before starting supplementation.

You should consult your GP before taking beetroot extract if you:

• Have been diagnosed with low blood pressure (hypotension) or experience frequent dizziness

• Are taking any medications for high blood pressure, heart conditions, or erectile dysfunction

• Have a history of kidney stones or kidney disease

• Have diabetes (particularly if using beetroot juice, which contains sugars; extracts typically contain minimal sugar)

• Are planning surgery—inform your surgeon and anaesthetist about all supplements and follow their guidance on whether to continue or stop

• Are pregnant, planning pregnancy, or breastfeeding

• Have any chronic medical conditions or take regular prescription medications

Seek medical advice if you experience any of the following whilst taking beetroot extract:

• Persistent or severe gastrointestinal symptoms that do not resolve

• Dizziness, light-headedness, or fainting episodes

• Unusual fatigue or weakness

• Signs of an allergic reaction (rash, itching, swelling)

• Severe allergic symptoms such as difficulty breathing or swelling of the face/tongue (call 999 immediately)

• Any unexpected or concerning symptoms

It is important to inform your GP about all supplements you are taking, as they may interact with prescribed medications. Beetroot can colour urine and stools red, which might be mistaken for blood; inform healthcare professionals about your beetroot consumption if you undergo tests, though faecal immunochemical tests (FIT) are usually unaffected.

If you are considering beetroot extract for a specific medical condition such as hypertension, it should not replace prescribed medications or lifestyle modifications recommended by your healthcare provider. NICE guidance (NG136) provides the framework for hypertension management in the UK, and supplements should complement, not substitute for, evidence-based treatments. Your GP can help you determine whether beetroot extract is appropriate for your individual circumstances and can monitor for potential interactions or adverse effects.

For general nutritional advice, you may also consult a registered dietitian or nutritionist, particularly if you are considering beetroot extract as part of a broader dietary strategy for cardiovascular health or athletic performance.

Frequently Asked Questions