Taking inorganic nitrate supplements does not change cognitive performance or blood flow in the brain in healthy adults.
From The Truth About Nitric Oxide Supplements Revealed · videoSee the scientific wording
Inorganic nitrate supplementation has no significant effect on cognitive function or cerebral blood flow in healthy adult populations.
Very strong evidence
Randomized trials2 high-quality studies support this claim.
What the research says
2 studies reviewedSupporting (2)
Randomized Controlled TrialHuman2024
This study gave healthy female athletes a beetroot juice with lots of nitrate and found it didn’t make them think any better or worse than when they drank a placebo juice. So, the nitrate didn’t change their brain performance.
Systematic Review With Meta-AnalysisMeta-analysis2019
Scientists looked at many studies where healthy adults took nitrate supplements and found no proof that it helped their memory or brain blood flow. So, the supplements don’t seem to make a difference.
Contradicting (0)
No contradicting studies found yet
That doesn't mean it's settled — it just means no study has tested the opposite.
Quality-weighted scoring: we follow the GRADE framework — each study is rated High, Moderate, Low, or Very Low based on study design, methodology rigor, and risk of bias. A single high-quality RCT can outweigh several weaker observational studies.
Scores reflect study quality, not just count.
When inorganic nitrate is consumed, it is absorbed into the blood, concentrated in saliva, and converted to nitrite by bacteria in the mouth. The nitrite enters the bloodstream and is converted to nitric oxide in tissues. Nitric oxide normally relaxes blood vessels to increase blood flow, but in healthy adults, this process does not change blood flow to the brain or improve thinking ability.
Score breakdown, mechanism chain, raw evidence, ideal studies needed & 2 supporting studies
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Taking inorganic nitrate supplements does not change cognitive performance or blood flow in the brain in healthy adults.
Mechanism
2 studiesEating nitrate-rich foods increases nitric oxide in the body, which normally opens blood vessels. But in healthy adults, this does not change blood flow to the brain or improve thinking skills, because the brain's blood vessels are already functioning at full capacity and do not respond to the extra nitric oxide.
When inorganic nitrate is consumed, it is absorbed into the blood, concentrated in saliva, and converted to nitrite by bacteria in the mouth. The nitrite enters the bloodstream and is converted to nitric oxide in tissues. Nitric oxide normally relaxes blood vessels to increase blood flow, but in healthy adults, this process does not change blood flow to the brain or improve thinking ability.
Ingested inorganic nitrate is absorbed in the small intestine and enters systemic circulation.
Nitrate is actively transported into saliva by salivary glands.
Oral microbiota reduce salivary nitrate to nitrite.
Nitrite is absorbed from the gastrointestinal tract into the bloodstream, increasing plasma nitrite concentration.
Nitrite is reduced to nitric oxide in tissues under hypoxic or acidic conditions.
Nitric oxide activates soluble guanylyl cyclase, increasing cyclic GMP and causing vascular smooth muscle relaxation.
Vasodilation occurs in systemic and cerebral vasculature, but cerebral blood flow remains unchanged in healthy adults.
Cerebral perfusion and neurovascular coupling are not altered, resulting in no change in cognitive function.
Evidence from Studies
Last searched 3mo ago
Supporting (2)
Community contributions welcome
This study gave healthy female athletes a beetroot juice with lots of nitrate and found it didn’t make them think any better or worse than when they drank a placebo juice. So, the nitrate didn’t change their brain performance.
Scientists looked at many studies where healthy adults took nitrate supplements and found no proof that it helped their memory or brain blood flow. So, the supplements don’t seem to make a difference.
Contradicting (0)
Community contributions welcome
Score Breakdown
No multi-axis breakdown available yet. The overall Pro / Against score above is the best signal.
- No clinical evidence is available; the score reflects mechanistic plausibility only.
What Would Prove This
Per GRADE and EBM methodology, here is what ideal scientific evidence would look like to definitively prove or disprove this claim, ordered from strongest to weakest.
Systematic Review and Meta-Analysis of Inorganic Nitrate Supplementation on Cognitive Function and Cerebral Blood Flow in Healthy Adults
Population: Healthy adults aged 18-70; Intervention: Oral inorganic nitrate supplementation (e.g., sodium nitrate or beetroot juice); Comparator: Placebo; Outcomes: Standardized cognitive test scores and cerebral blood flow measured via MRI or Doppler ultrasound; Duration: Minimum 4 weeks of daily supplementation with follow-up assessments.
Double-Blind, Placebo-Controlled Trial of Inorganic Nitrate on Cognitive Performance and Cerebral Perfusion in Healthy Adults
Population: Healthy adults aged 25-65; Intervention: Daily inorganic nitrate (e.g., 6.4 mmol nitrate); Comparator: Matched placebo; Outcomes: Primary: Change in executive function (e.g., Stroop test) and middle cerebral artery blood flow velocity; Secondary: Working memory and cerebral oxygenation; Duration: 8 weeks with pre- and post-intervention neuroimaging and cognitive testing.
Prospective Cohort Study of Dietary Inorganic Nitrate Intake and Long-Term Cognitive Decline and Cerebral Blood Flow in Healthy Adults
Population: Healthy adults followed over 5 years; Intervention: Natural variation in dietary nitrate intake measured via food frequency questionnaires; Comparator: Low vs. high nitrate consumers; Outcomes: Annual cognitive assessments and periodic cerebral blood flow measurements via MRI; Duration: 5 years of follow-up.
Cross-Sectional Analysis of Inorganic Nitrate Intake and Cognitive Performance in Healthy Adult Populations
Population: Healthy adults aged 18-70 assessed at one time point; Intervention: Single measurement of dietary nitrate intake; Comparator: Groups stratified by nitrate intake level; Outcomes: Single-session cognitive testing and cerebral blood flow measurement; Duration: Single assessment.
In Vitro Investigation of Inorganic Nitrate Metabolites on Human Cerebral Endothelial Cell Function and Neuronal Activity
Population: Human cerebral endothelial cells and neuronal cultures; Intervention: Exposure to physiologically relevant concentrations of nitrate and nitrite; Comparator: Untreated controls; Outcomes: Changes in nitric oxide production, mitochondrial function, and neuronal signaling markers; Duration: 24–72 hour exposures.