CHAMGAP
APPROVEDReviewed and approved by the Chamgap Editorial Team (2026-07-19). The draft was written by AI, the existence of all 3 cited sources was verified at the original page, and the verdict passed blind grading and adversarial audit. Methodology v0.6.
Verdict No. 678 · Search date 2026-07-19 · Methodology v0.6

OxyStorm red spinach extract,
does it really help with Increased nitric oxide, exercise endurance, and performance?

30-Second Summary
C
Evidence Grade C · 45 · Safety caution
Some exercise-test signals exist, but small branded-ingredient studies do not establish a reliable endurance or competition-performance benefit
What the
research shows
The exercise-performance claim for OxyStorm red-spinach nitrate is rated C. A 2025 systematic review contained only four red- or green-spinach randomized trials with 94 participants, using different sports, doses, durations, and outcomes. In a 15-person OxyStorm trial, plasma nitrate and ventilatory threshold increased, but time to exhaustion and peak oxygen uptake did not, and the manufacturer funded the study.
What the
ads claim
Marketing converts higher nitrate or NO directly into endurance, strength, and competition performance. Results or imagery from finished blends containing beet, pomegranate, aronia, or other ingredients cannot be attributed to OxyStorm alone.
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Useful facts when choosing a product

  • OxyStorm is a branded red-amaranth leaf extract standardized for nitrate and is distinct from verdict 25 on spinach thylakoids and verdict 77 on beet-derived nitrate. Publications and finished-product labels use both Amaranthus dubius and A. tricolor, so botanical identity and standardization require confirmation.
  • Commercial finished products may also contain beet, pomegranate, aronia, flavors, or other sports ingredients, so the labeled OxyStorm dose and total nitrate should be checked.
  • Nitrate is converted through oral bacteria to nitrite and nitric oxide, so antibacterial mouthwash, meals, and timing can affect exposure.
  • Reported short-term adverse effects are generally mild, but gastrointestinal discomfort, dizziness, and lower blood pressure are possible, warranting caution with hypotension or antihypertensive medicines.
Gap Measurement · Verdict 678 · C 45
What advertising claims
What independent, higher-quality research supports
△ GAP
01

What the research actually shows

Wen et al. reviewed four spinach-extract randomized trials with 94 participants and summarized favorable findings in many reported performance measures, while emphasizing the small sample and follow-up. In the 15-person crossover trial by Moore et al., 1 g of OxyStorm raised plasma nitrate and ventilatory threshold but did not significantly improve nitrite, time to exhaustion, or peak oxygen uptake. A seven-day trial by Haynes et al. in 10 resistance-trained men found no effect on bench-press performance, muscle oxygenation, or cognition.

02

Why this is classified as C (45)

Positive performance signals are not dismissed, but four randomized trials with 94 participants, branded-ingredient and manufacturer concentration, disparate surrogate exercise tests, and null findings limit the verdict to C with 45 points. Mild gastrointestinal and blood-pressure effects remain separate safety issues.

Counterpoint. An athlete may test for a small individual response, but this does not replace validated training, carbohydrate, hydration, and sleep. Supplement-contamination controls for competition are also separate from ingredient efficacy.

Rejudgment record. New verdict — Integrated the heterogeneous four-trial, 94-participant evidence with the manufacturer-funded OxyStorm trial that improved ventilatory threshold but not time to exhaustion or peak oxygen uptake, applying rule ① for surrogates and rule ②-b for branded-ingredient concentration

Sub-claim grades by effect

This ingredient is marketed for several effects. A single overall grade blends strong and weak claims together, so each effect is graded separately here. The overall grade reflects the strongest disconfirming or core claim.

Effect (sub-claim)GradeBasis
Improved exercise endurance and performanceCSome measures are positive, but only four trials with 94 participants exist, with brand concentration, heterogeneity, and null outcomes.
Increased nitric oxide?Surrogates such as plasma nitrate or exhaled NO exist, but a direct NO increase linked to clinical performance is not established.
Attribution of a blended finished-product effect to OxyStorm alone?No human efficacy literature isolates the ingredient's contribution within blends containing beet, pomegranate, aronia, or other components.

Cross-check — Codex and Claude

This verdict was drafted by Codex through literature review and source-existence checks, cross-checked through blind grading and adversarial audit, and settled by reapplying the methodology boundary rules. Cases with split grades were resolved through rejudgment.
03

Evidence Table

StudyDesignSampleFundingEndpointResultWeight
Study 1Systematic review of randomized trials of spinach extract94Authors reported no funding or conflicts of interestExercise performance, body composition, and adverse eventsMany reported measures were favorable, but red and green sources and test methods were mixed and samples and follow-up were small.Key but very limited synthesis
Study 2Randomized double-blind placebo-controlled crossover trial15Contract funding from DolCas Biotech; OxyStorm was usedPlasma nitrate and nitrite, ventilatory threshold, time to exhaustion, and peak oxygen uptakeNitrate and ventilatory threshold increased, but nitrite, time to exhaustion, and peak oxygen uptake did not significantly improve.Small direct branded-ingredient trial with mixed results
Study 3Randomized double-blind placebo-controlled crossover trial10The paper reported no external research fundingBench-press performance, muscle oxygenation, and cognitionSeven days of red-spinach extract did not improve physical performance, muscle oxygenation, or cognition.Small direct null trial
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Receipt — 3 References

All 3 cited sources were verified for existence at the original page (as of 2026-07-19).

Wen J, Syed B, Abed I, et al. Improved Effect of Spinach Extract on Physical Performance: A Systematic Review of Randomized Controlled Trials. Cureus. 2025;17(1):e77840. PMID: 39991395. PMCID: PMC11845096. DOI: 10.7759/cureus.77840.
checked
Moore AN, Haun CT, Kephart WC, et al. Red Spinach Extract Increases Ventilatory Threshold during Graded Exercise Testing. Sports (Basel). 2017;5(4):80. PMID: 29910440. PMCID: PMC5969023. DOI: 10.3390/sports5040080.
checked
Haynes JT 4th, Townsend JR, Aziz MA, et al. Impact of Red Spinach Extract Supplementation on Bench Press Performance, Muscle Oxygenation, and Cognitive Function in Resistance-Trained Males. Sports (Basel). 2021;9(6):77. PMID: 34071862. PMCID: PMC8227312. DOI: 10.3390/sports9060077.
checked
Draft and rewrite: Codex (AI) · Verification: Codex blind grading and adversarial audit · Final adjudication: Claude
Reviewed and approved: Chamgap Editorial Team · Approval date: 2026-07-19 · Corrections: none

Cite this verdict

OxyStorm red spinach extract x nitric oxide and exercise performance Evidence Grade C card
[Chamgap] OxyStorm red spinach extract x nitric oxide and exercise performance — Evidence Grade C·45. 3 cited sources checked. Source: https://chamgap.com/en/verdicts/sports/oxystorm-red-spinach-nitrate-exercise-performance/ · CC BY 4.0

CC BY 4.0 — free to use with attribution; do not distort grades, numbers, or verdict meaning.

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What this document does and does not do

Chamgap is an information source. It reports what research has and has not confirmed; it does not tell readers what to take or buy. That decision belongs to readers and, when needed, medical or legal professionals. This verdict reflects literature available up to the search date and may change as new research appears. Nothing here is medical advice.