Does tart cherry and beetroot extracts widen blood vessels? Both supplements contain naturally occurring compounds that may support vascular health through different mechanisms. Beetroot extract is rich in dietary nitrates, which the body converts to nitric oxide—a molecule that promotes blood vessel widening. Tart cherry extract contains polyphenolic compounds with antioxidant properties that may support the inner lining of blood vessels. Whilst research suggests modest effects, particularly for beetroot, these are food supplements regulated under UK food law, not medicines. They should complement, not replace, prescribed treatments for cardiovascular conditions.

How Tart Cherry and Beetroot Extracts Affect Blood Vessels

Tart cherry and beetroot extracts have gained attention for their potential cardiovascular benefits, particularly their ability to influence blood vessel function. Both supplements contain naturally occurring compounds that may support vascular health through complementary mechanisms, though it is important to understand that they are not medicines and should not replace prescribed treatments.

Beetroot extract is particularly rich in dietary nitrates, which the body converts into nitric oxide—a crucial signalling molecule that promotes vasodilation (the widening of blood vessels). This process occurs when nitrates are reduced to nitrites by bacteria in the mouth, and subsequently converted to nitric oxide in the bloodstream and tissues. The resulting increase in nitric oxide availability can lead to improved blood flow and modest reductions in blood pressure. It's worth noting that using antibacterial mouthwash can significantly reduce this conversion process, potentially diminishing the vascular effects.

Tart cherry extract (Prunus cerasus) contains high concentrations of polyphenolic compounds, particularly anthocyanins, which give the fruit its distinctive deep red colour. These bioactive compounds possess antioxidant and anti-inflammatory properties that may support endothelial function—the health of the inner lining of blood vessels. Whilst tart cherry's effects on blood vessels are less direct than beetroot's nitrate pathway, preliminary research suggests these polyphenols may enhance nitric oxide bioavailability by reducing oxidative stress that would otherwise degrade this important molecule.

Both extracts are available as dietary supplements in various forms including capsules, powders, and concentrated juices. In the UK, they are regulated as food supplements rather than medicines. Currently, there are no authorised health claims on the GB Nutrition and Health Claims Register regarding these supplements and blood vessel function. The mechanisms described above are biologically plausible, but clinical significance in real-world settings requires careful evaluation of the available research evidence.

The Science Behind Nitric Oxide and Vascular Health

Nitric oxide (NO) is a gaseous signalling molecule that plays a fundamental role in cardiovascular physiology. Produced primarily by endothelial cells lining blood vessels, nitric oxide acts as a potent vasodilator, helping to regulate blood pressure, improve blood flow, and maintain vascular health. Understanding this pathway is essential to appreciating how dietary supplements like beetroot and tart cherry extracts might influence cardiovascular function.

The endothelium produces nitric oxide through the enzymatic conversion of L-arginine by endothelial nitric oxide synthase (eNOS). Once released, NO diffuses into the smooth muscle cells of blood vessel walls, triggering a cascade that results in muscle relaxation and vessel widening. This process reduces vascular resistance and can lower blood pressure. However, nitric oxide is highly reactive and short-lived, with a half-life of only seconds, making continuous production essential for sustained vascular benefits.

The dietary nitrate-nitrite-nitric oxide pathway provides an alternative route to NO production that does not rely solely on eNOS activity. When you consume nitrate-rich foods or supplements like beetroot extract, salivary bacteria convert these nitrates to nitrites, which are then absorbed and further reduced to nitric oxide in the blood and tissues, particularly in areas of low oxygen availability or acidic conditions. This pathway becomes increasingly important when endothelial function is compromised, as occurs with ageing, diabetes, or cardiovascular disease. Importantly, the use of antibacterial mouthwash or certain antibiotics can disrupt the oral bacteria necessary for this conversion, potentially reducing the vascular benefits of nitrate-rich supplements.

Oxidative stress represents a significant threat to nitric oxide bioavailability. Reactive oxygen species can rapidly inactivate NO, reducing its beneficial effects. This is where the antioxidant properties of tart cherry polyphenols may play a supportive role, potentially protecting existing nitric oxide from degradation and supporting the overall efficiency of vascular signalling pathways. The interplay between these mechanisms highlights the complex nature of vascular health and the potential for dietary interventions to offer modest support.

Evidence for Blood Vessel Widening Effects

The scientific evidence supporting blood vessel widening effects differs considerably between beetroot and tart cherry extracts, with beetroot demonstrating more robust and consistent findings in clinical research.

Beetroot extract evidence: Multiple systematic reviews and meta-analyses have examined beetroot juice and extract supplementation, generally showing modest but statistically significant reductions in blood pressure. Recent meta-analyses have confirmed that dietary nitrate from beetroot can reduce systolic blood pressure by approximately 3-5 mmHg in both healthy adults and those with hypertension. UK research, including a trial by Kapil et al. (2015), demonstrated that concentrated beetroot juice providing about 6-8 mmol of nitrate (approximately 370-500 mg) reduced blood pressure in hypertensive patients. Studies using flow-mediated dilation (FMD)—a measure of endothelial function—have demonstrated improved vascular responsiveness following beetroot supplementation. However, the magnitude of effect is generally modest, and individual responses vary considerably based on baseline cardiovascular health, oral microbiome composition, and concurrent medication use.

Tart cherry extract evidence: The evidence base for tart cherry's direct vascular effects is less developed. Whilst several small studies have reported improvements in markers of vascular function and modest blood pressure reductions, the research is limited by small sample sizes and methodological variations. A 2019 study in the journal Food & Function found that tart cherry juice consumption improved endothelial function in older adults, but larger, well-controlled trials are needed to confirm these preliminary findings. The proposed mechanisms—primarily antioxidant and anti-inflammatory effects—are biologically plausible but require further validation.

Important limitations: Most studies have been conducted in healthy volunteers or those with mild hypertension, limiting generalisability to clinical populations. The quality and concentration of active compounds vary significantly between commercial products, making it difficult to translate research findings into practical recommendations. There are no authorised health claims on the GB Nutrition and Health Claims Register regarding these supplements and blood vessel function or blood pressure. These extracts should be viewed as potentially supportive dietary additions rather than therapeutic interventions.

Safe Use and Recommended Dosages in the UK

In the UK, tart cherry and beetroot extracts are classified as food supplements regulated under food law by the Food Standards Agency (FSA) and Office for Product Safety and Standards (OPSS). They are not medicines and have not been evaluated by the MHRA for therapeutic claims.

Beetroot extract dosing: Research studies typically use doses providing approximately 6-12 mmol of nitrate (about 370-740 mg), often delivered as 60-140 ml of concentrated beetroot juice. Commercial supplements vary widely, with capsules typically providing 500-1000 mg of beetroot extract per serving, though the actual nitrate content may not be clearly stated. When selecting products, look for those that specify nitrate content and have been tested for quality by independent third parties. The European Food Safety Authority (EFSA) has established an Acceptable Daily Intake (ADI) for nitrate of 3.7 mg/kg body weight per day, which provides a safety context for supplementation.

Tart cherry extract dosing: Studies examining vascular effects have used doses ranging from 480 mg to several grams of tart cherry powder or the equivalent of 200-300 ml of concentrated tart cherry juice daily. Standardisation to anthocyanin content (typically 10-25% in quality extracts) provides some assurance of active compound delivery.

Safety considerations: Both supplements are generally well-tolerated, but certain precautions apply:

• Beetroot extract may cause harmless beeturia (pink or red urine) and can temporarily colour stools. The nitrate content may have an additive effect with blood pressure medications, potentially enhancing their effects. People taking medications for erectile dysfunction (PDE-5 inhibitors) should be aware of possible additive blood pressure-lowering effects, though this is less concerning than the absolute contraindication between PDE-5 inhibitors and prescribed nitrate medicines. Beetroot juice contains potassium and oxalates, which may be relevant for people with kidney disease.

• Tart cherry extract in juice form contains natural sugars that should be considered by people with diabetes, though capsules or extracts may contain minimal sugars. There is limited evidence that tart cherry may have mild antiplatelet effects due to its salicylate content, but clinically significant interactions with anticoagulants are not well established.

• Both supplements may cause mild gastrointestinal upset in some individuals, particularly at higher doses.

Pregnant or breastfeeding women should consult healthcare professionals before using these supplements, as safety data in these populations is limited. Always purchase supplements from reputable UK suppliers who comply with food safety regulations. If you experience any adverse effects, report them through the MHRA Yellow Card scheme.

When to Consult Your GP About Supplements

Whilst tart cherry and beetroot extracts are widely available and generally considered safe, certain circumstances warrant professional medical advice before commencing supplementation or if problems arise during use.

Before starting supplementation, consult your GP if you:

• Have been diagnosed with cardiovascular disease, including hypertension, coronary artery disease, or heart failure

• Take prescribed medications, particularly antihypertensives, anticoagulants, nitrate-based treatments, or medications for erectile dysfunction

• Have diabetes or impaired glucose tolerance, particularly if considering juice forms which contain natural sugars (capsule/extract forms may have minimal sugar content)

• Have kidney disease, as beetroot juice contains significant potassium and oxalates which may be problematic in chronic kidney disease

• Are scheduled for surgery, as a precaution discuss all supplements with your surgical/anaesthetic team

• Have a history of kidney stones, as beetroot is high in oxalates

Seek prompt medical attention if you experience:

• Symptoms of hypotension (dizziness, fainting, extreme fatigue) after starting supplementation, particularly if taking blood pressure medications

• Allergic reactions such as rash, itching, swelling, or difficulty breathing

• Unusual bleeding or bruising whilst taking supplements

• Persistent gastrointestinal symptoms including severe abdominal pain, diarrhoea, or vomiting

Important principles for supplement use:

Supplements should never replace prescribed medications without explicit guidance from your healthcare provider. If you have elevated blood pressure or cardiovascular concerns, these require proper medical assessment and evidence-based treatment. NICE guidelines (NG136) for hypertension management emphasise lifestyle modifications (including reduced salt intake and a diet rich in vegetables and fruits) alongside appropriate pharmacological treatment when indicated.

Your GP can help determine whether these supplements are appropriate for your individual circumstances, advise on potential interactions with your current medications, and ensure that any cardiovascular symptoms receive proper investigation rather than being masked by supplement use. Regular blood pressure monitoring and medication review remain essential components of cardiovascular care that supplements cannot replace.

If you suspect any adverse effects from supplements, report them through the MHRA Yellow Card scheme.

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