Nitralis Clinical Trial: Results, Limitations and Dose Differences

The Nitralis clinical trial is a published, randomized, placebo-controlled pilot investigating a branded nitric-oxide supplement. It supplies useful product-specific research, but the outcome measured matters: the investigators used semi-quantitative saliva test strips, not laboratory blood nitric oxide measurements or direct tests of vascular health. Here is what the 2025 study actually found, how its methods affect interpretation, and how it relates to the product sold today.

What was studied?

The October 2025 report, published in Biomedical Journal of Scientific & Technical Research, described an 85-person, 30-day pilot. Forty-three adults completed the Nitralis arm and 42 completed the placebo arm. Participants were aged 30–70. People with significant cardiovascular disease, uncontrolled hypertension, pregnancy or concurrent use of other nitric-oxide supplements were excluded. The report describes random assignment to two parallel groups and states that both participant groups were blinded, although independent verification of allocation concealment and the protocol was not available.

The indexed study record describes a proprietary formula containing fermented beet, magnesium ascorbate and epimedium. The intervention section refers to a 400 mg daily capsule. The current retail listing specifies 400 mg per capsule but recommends 800 mg per day. The paper does not establish that twice the tested daily amount produces twice the observed response.

The outcomes: what the test strips measured

At baseline and on days one, 15 and 30, participants took colorimetric saliva-strip tests with readings across a stated 10–870-unit range. The prespecified primary outcome was each participant's change from baseline to day 30. A responder was defined as achieving an increase of at least 70 strip units. These details are essential because a strip color change is an indirect biochemical marker. It is neither an absolute blood nitric-oxide concentration nor a direct measure of blood-vessel dilation.

What were the reported results?

The paper also reports an average percentage change from baseline of +226% in the active arm, alongside a +64% median change. Both percentages refer to the test-strip measurement. Large mean percentage changes can be influenced by low starting values and skewed responses; the median and between-group absolute change provide additional context. The responder result was statistically different under the authors' prespecified definition. See the original publication for the figures and tables.

Does this prove that Nitralis improves circulation or blood pressure?

No. The trial did not measure clinic or ambulatory blood pressure, flow-mediated dilation, cardiac outcomes, aerobic exercise performance, erectile-function scores or mortality. Human studies of standardized beetroot juice and dietary nitrate have measured some of those outcomes, but their results cannot simply be transferred to a proprietary combination with an unverified standardized nitrate dose. For that wider evidence, use our Nitric Oxide Data Center and the 2025 dietary-nitrate meta-analysis.

Why the salivary measurement matters

Salivary nitrate and nitrite biology is part of the body's enterosalivary nitrate cycle. An assay that detects a change in this pathway can therefore be biologically relevant. Nevertheless, test strips are semi-quantitative and susceptible to assay-specific variability. A 2019 strip-validation study found that strips tracked some changes but could not reliably replace quantitative laboratory measures for absolute concentrations. A separate 2017 comparison reported that saliva-strip readings were poor substitutes for the tested circulating measurements. These studies do not invalidate the Nitralis group's reported within-assay difference; they limit the conclusions that can reasonably follow from it.

Funding, conflicts and the 400 mg versus 800 mg difference

The Nitralis study explicitly states that it was funded by DoNotAge and that all authors were affiliated with the manufacturer. Manufacturer sponsorship does not automatically make an outcome false, but independent replication with preregistered protocols and objectively measured clinical endpoints would increase confidence. The original report's 400 mg daily regimen differs from today's 800 mg recommended retail serving. A current batch-specific report confirming constituent quantities and standardized nitrate exposure was not independently established during this review.

What about safety?

The authors report no adverse events during the 30-day pilot. That observation is reassuring within its short follow-up and selected population, not a demonstration of long-term safety in people with heart disease, pregnancy or polypharmacy. Anyone using prescription nitrates, blood-pressure medications or PDE5 inhibitors should obtain individual professional guidance. Prescription organic nitrates and sildenafil-type medicines must never be combined, although dietary nitrate and organic nitrate drugs are not chemically identical.

Our interpretation

Publishing a randomized study on a branded finished formula is a meaningful differentiator from marketing based entirely on unrelated ingredients. The data support a preliminary product-specific salivary biomarker effect after 30 days. They do not support a claim that Nitralis has been shown to improve cardiovascular clinical outcomes, sexual function, athletic performance or longevity. Those questions require appropriately powered, independently assessed studies with validated measurements.

Common questions

Was this a human randomized trial?

Yes, the report describes an 85-person randomized placebo-controlled pilot. It is a single, manufacturer-funded study.

Was the reported increase greater than 200%?

The paper reports +226% as the active group's mean percentage change in saliva-strip readings, not as a validated increase in circulating nitric oxide.

Is the tested dose the same as the retail dose?

No: 400 mg daily is reported in the pilot and 800 mg daily is today's standard retail recommendation. Formula and batch equivalence still need confirmation.

Research sources

• Baily et al., 2025 — Original Nitralis report
• Babateen et al., 2019 — Saliva-strip validation
• Modi et al., 2017 — Saliva/serum point-of-care validation
• Norouzzadeh et al., 2025 — Dietary nitrate synthesis