Dietary Nitrates

Beetroot and leafy greens improve blood flow, exercise efficiency, and blood pressure — with stronger effects in older adults

Exercise Performance Blood Pressure Heart Health Blood Flow Oxygen Efficiency

Evidence strength:

Strong (exercise O₂ efficiency, BP); effects larger in older adults

Overview

Dietary nitrates are compounds found naturally in high concentrations in beetroot, spinach, rocket (arugula), celery, and other leafy vegetables. In the body, nitrate is converted — via nitrite — to nitric oxide (NO), a signalling molecule that causes blood vessels to dilate. This vasodilation improves blood flow, reduces blood pressure, and lowers the oxygen cost of physical effort.

Nitrate supplements are most commonly taken as concentrated beetroot juice shots (e.g., 70 ml "shots" containing ~400 mg nitrate), beetroot powder, or as direct dietary intake from vegetables. The conversion of nitrate to nitrite requires oral bacteria; using antibacterial mouthwash blocks this pathway and reduces efficacy.

Key fact for seniors The ability to produce nitric oxide through other pathways declines with age, making the dietary nitrate→nitrite→NO pathway increasingly important in older adults. Several studies have found that the exercise performance and blood pressure benefits of nitrate supplementation are greater in older individuals than in younger ones.

What the Evidence Shows

Exercise efficiency and oxygen consumption

One of the most well-replicated findings in sports nutrition is that dietary nitrate reduces the oxygen cost (VO₂) of submaximal exercise by 3–5%. This means the same physical effort requires less oxygen — effectively improving endurance and delaying fatigue. For older adults, this translates to being able to sustain activities (walking, stair climbing, gardening) for longer with less breathlessness.

Blood pressure reduction

Multiple meta-analyses confirm that dietary nitrate (predominantly from beetroot juice) reduces systolic blood pressure by approximately 4–5 mmHg and diastolic by 2–3 mmHg. These reductions are clinically meaningful — comparable to some antihypertensive medications — and occur within 2–3 hours of ingestion.

Functional capacity in older adults

Several trials specifically in older adults show that beetroot juice supplementation improves 6-minute walk distance, sit-to-stand performance, and gait speed — markers closely linked to independence and quality of life. The improvement in muscle efficiency may be partly responsible, alongside better blood flow to exercising muscles.

Cognitive function

Nitric oxide increases cerebral blood flow. Preliminary trials show that acute beetroot juice intake improves cognitive processing speed in older adults. Longer-term studies are needed, but the mechanism is biologically plausible.

Dosage by Age Group

Group	Recommended Intake	Notes
General adults	300–500 mg nitrate/day	Equivalent to 500 ml beetroot juice or ~70 ml concentrated shot
Seniors — blood pressure	300–400 mg nitrate/day	Daily use for sustained BP reduction; effects peak 2–3 hours post-ingestion
Seniors — exercise performance	300–600 mg nitrate 2–3 hours pre-exercise	Acute dose strategy; consistent with most published trials
Food equivalent	~200–300 g of raw spinach or rocket, or 2 medium beetroots	Cooking reduces nitrate content by 30–50%

Australian brands

What to buy

Dietary nitrates are most commonly consumed as beetroot juice or concentrated beetroot shots. These are the forms used in most clinical trials. Beetroot powder (in capsules or loose) is also available, though nitrate content per serve can vary. There is no widely used "nitrate supplement pill" — whole-food preparations remain the standard approach.

Brand	Form	Typical product	Approx. cost
Beet It (James White)	Concentrated shot (70 ml)	Sport Nitrate 400 shot (~400 mg nitrate per bottle)	$4–6 per shot
Biotta	Juice (500 ml)	Organic Beetroot Juice (~250–350 mg nitrate per 500 ml)	$8–12 per bottle
Ceres Organics	Juice (500 ml)	Organic Beetroot Juice (widely available in Woolworths/Coles)	$6–9 per bottle
Nutra-Life / Health food brands	Capsule (powder)	Beetroot Concentrate 500 mg caps (60 caps) — variable nitrate content	$18–26
Blackmores	Not currently available	No dedicated nitrate/beetroot product in current range	—

Prices are approximate retail (supermarkets, health food stores, Chemist Warehouse, online). For seniors using nitrates for blood pressure or exercise support, Beet It concentrated shots provide a reliable, measured dose and are available in some Australian health food stores and online. Ceres and Biotta juices are the easiest everyday option from supermarkets. Note: do not use antibacterial mouthwash before consuming — it blocks the conversion of nitrate to its active form.

Safety & Cautions

Important cautions Beetroot juice causes harmless red or pink colouration of urine and stools (beeturia) — this is not dangerous but can be alarming. Do not use antibacterial mouthwash if taking nitrate supplements for performance — it kills the oral bacteria needed for nitrate-to-nitrite conversion, blocking the effect entirely.

Drug interactions Dietary nitrates interact significantly with PDE5 inhibitors (sildenafil/Viagra, tadalafil/Cialis) — combined use causes a dangerous drop in blood pressure and is contraindicated. Also use with caution alongside antihypertensive medications; the combined blood-pressure-lowering effect may be excessive. Discuss with your physician if you are on any blood pressure treatment.

Synergistic Combinations

Nitrates + Creatine: Nitrates improve oxygen delivery and blood flow, while creatine provides rapid energy for muscle contraction. Together, they address different limiting factors in exercise performance and may have additive benefits on overall exercise capacity in older adults.
Nitrates + Beta-Alanine: Nitrates reduce the oxygen cost of effort; beta-alanine buffers muscle acidity. They work independently and can be combined for a broader improvement in exercise endurance and tolerance.
Nitrates + Omega-3: Both support cardiovascular health through different mechanisms — nitrates via vasodilation and blood pressure, omega-3 via triglyceride reduction and anti-inflammation. Their combined use is likely additive for heart health.
Nitrates + Magnesium: Magnesium helps maintain vascular tone and blood pressure; nitrates cause acute vasodilation. Together they provide complementary blood pressure support.

📚 Key Scientific References

1.Lara J et al. Effects of inorganic nitrate and beetroot supplementation on endurance performance and metabolism in healthy adults: a systematic review and meta-analysis. Eur J Nutr. 2016;55(3):1133–1141 — and: Siervo M et al. Inorganic nitrate and beetroot juice supplementation reduces blood pressure in adults: a systematic review and meta-analysis. J Nutr. 2013;143(6):818–826, PMID 23596162

Meta-analysis confirming inorganic nitrate/beetroot juice reduces systolic blood pressure by 4.4 mmHg — comparable to low-dose antihypertensive medication.
2.Bahadoran Z et al. Nitrate Derived From Beetroot Juice Lowers Blood Pressure in Patients With Arterial Hypertension: A Systematic Review and Meta-Analysis. J Nutr. 2022;152(7):1757–1769, PMID 35369064

Meta-analysis specifically in hypertensive patients: beetroot juice significantly reduced systolic BP by 3.55 mmHg and diastolic by 1.32 mmHg.
3.Thompson C et al. Acute Supplementation with Nitrate-Rich Beetroot Juice Causes a Greater Increase in Plasma Nitrite and Reduction in Blood Pressure of Older Compared to Younger Adults. Nutrients. 2019;11(7):1636, PMID 31336633

RCT showing that older adults experience greater plasma nitrite elevation and greater blood pressure reduction from beetroot juice than younger adults — confirming age-related benefit.
4.Stanaway L et al. Performance and Health Benefits of Dietary Nitrate Supplementation in Older Adults: A Systematic Review. Nutrients. 2017;9(11):1171, doi:10.3390/nu9111171

Systematic review in older adults: dietary nitrate supplementation improved physiological exercise performance, with evidence for cardiovascular and cerebrovascular benefits.
5.Jones AM et al. Dietary Nitrate and Physical Performance. Annu Rev Nutr. 2018;38:303–328, PMID 29975527

Comprehensive review by leading nitrate researchers confirming 3–5% reduction in oxygen cost of submaximal exercise, with greater effects in older and less fit individuals.