Beetroot supplements have more clinical evidence behind them than almost any other sports nutrition ingredient. Over 20 randomised controlled trials confirm dietary nitrates from beetroot — converted to nitric oxide in the body — reduce the oxygen cost of submaximal exercise, lower blood pressure and improve time-trial performance. Here is the mechanism and who benefits most.
The Nitrate-Nitrite-Nitric Oxide Pathway
Beetroot’s effects are mediated by its exceptionally high dietary nitrate content. The mechanism:
- Dietary nitrate (NO3) from beetroot is absorbed in the small intestine into the bloodstream
- Blood nitrate is concentrated in the salivary glands and secreted into saliva
- Oral bacteria reduce salivary nitrate to nitrite (NO2)
- Swallowed nitrite is reduced to nitric oxide (NO) in the acidic stomach environment — and systemically by various enzymatic pathways
- Nitric oxide causes vascular smooth muscle relaxation (vasodilation), increases blood flow and oxygen delivery to muscles, and reduces the ATP cost of muscle contraction
This last step — reduced ATP cost of muscle contraction — is the mechanism behind beetroot’s exercise performance effects. It is not primarily about more oxygen delivery; it is about the muscles needing less oxygen to produce the same force output.
What Does the Clinical Evidence Show?
Exercise performance — very strong evidence
A landmark 2009 study by Lansley et al. at the University of Exeter found that beetroot juice supplementation reduced the oxygen cost of cycling by 19% and significantly improved time to exhaustion. Subsequent meta-analyses of 22+ trials confirm consistent reductions in oxygen cost (VO2) during submaximal exercise and improvements in time-trial performance across cycling, running and swimming. Effects are most pronounced in recreational athletes — elite athletes may show diminished response due to already-optimised nitric oxide systems.
Blood pressure reduction — strong evidence
Multiple RCTs confirm beetroot juice supplementation reduces blood pressure significantly — a 2013 meta-analysis found mean reductions of approximately 4.4/1.1 mmHg from a single dose. The nitric oxide-mediated vasodilation effect is dose-dependent and appears within 2–3 hours of ingestion.
Antioxidant activity — moderate evidence
Betalains — the pigments giving beetroot its distinctive colour — have significant antioxidant and anti-inflammatory activity. Betalain-rich extracts reduce markers of exercise-induced muscle damage and accelerate recovery in multiple trials.
When Should You Take Beetroot Supplements?
- For exercise performance: 2–3 hours before training, as nitric oxide peaks at 2–3 hours post-ingestion. For sustained effects, daily supplementation builds tissue nitrate stores.
- For blood pressure: daily supplementation produces sustained lowering effects
- Loading: some research shows 3–6 days of daily supplementation produces greater effects than single-dose supplementation
What Dose Is Effective?
Trials typically use 6–8 mmol dietary nitrate — equivalent to approximately 500ml beetroot juice or 50mg concentrated nitrate. Beetroot supplements should specify nitrate content where possible. Montmorency cherry combined with beetroot provides complementary antioxidant (anthocyanin) benefits for recovery alongside the nitrate performance effect.
Important: Mouthwash Negates Beetroot Benefits
Using antibacterial mouthwash eliminates the oral bacteria responsible for converting nitrate to nitrite — the essential second step in the pathway. Research confirms that antibacterial mouthwash completely eliminates the blood pressure-lowering effect of beetroot supplementation. Avoid mouthwash use around beetroot supplementation.
RedPunch by BioBodyBoost combines concentrated beetroot with montmorency cherry — addressing both the nitrate performance pathway (beetroot) and the antioxidant recovery pathway (cherry anthocyanins). Halal certified, vegan, UK GMP. Browse the sports range.
