Home Ingredients Vinitrox™ (Grape and Apple Polyphenols — Nexira)
Athletic Performance

Vinitrox™ (Grape and Apple Polyphenols — Nexira)

Evidence Level
Limited
0 Clinical Trials
3 Documented Benefits
2/5 Evidence Score

Vinitrox™ is a branded blend of grape and apple polyphenols from Nexira, marketed to support nitric oxide production, blood flow, and physical performance. Polyphenols from grape and apple are recognized for vascular and antioxidant effects, though independent clinical evidence specific to this branded blend is limited and mostly held by the manufacturer.

Studied Dose Around 500 mg per day, often taken before exercise.
Active Compound A proprietary blend of polyphenols (including flavanols and procyanidins) from grape and apple.

Benefits

Nitric oxide and blood flow (proposed mechanism, not measured for Vinitrox)

Grape and apple polyphenols may support endothelial nitric oxide, but no Vinitrox trial has measured nitric oxide or blood flow. This is a proposed mechanism, not a demonstrated effect of the blend.

Exercise performance support

In a single manufacturer-funded trial, the blend increased time to exhaustion by about 10% versus placebo. The mechanism was not measured, and independent trials on the specific blend are limited.

Antioxidant polyphenols

The flavanols and procyanidins it provides act as antioxidants that help counter exercise-related oxidative stress.

Mechanism of action

1

Endothelial nitric oxide support

Polyphenols such as those in grape and apple can promote nitric oxide synthase activity in blood vessel linings, supporting vasodilation and blood flow.

2

Antioxidant activity

Procyanidins and flavanols scavenge free radicals, which may protect vascular function during physical stress.

Clinical trials

Side effects and drug interactions

Common Potential side effects

Generally well-tolerated — dietary polyphenols are well tolerated.
Mild digestive upset is possible at higher intakes.
Independent human safety data on the specific blend are limited.

Important Drug interactions

Blood thinners — polyphenols may have a mild additive effect; monitor.
Blood pressure medication — possible additive vasodilation; use caution.
Tell your doctor about supplements if you take cardiovascular medication.

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Frequently asked questions about Vinitrox™ (Grape and Apple Polyphenols — Nexira)

What is Vinitrox?

Vinitrox™ is a branded blend of grape and apple polyphenols from Nexira, marketed to support nitric oxide production, blood flow, and physical performance. Polyphenols from grape and apple are recognized for vascular and antioxidant effects, though independent clinical evidence specific to this branded blend is limited…

What is Vinitrox used for?

Vinitrox is researched primarily for Athletic Performance. Grape and apple polyphenols may support endothelial nitric oxide, but no Vinitrox trial has measured nitric oxide or blood flow. This is a proposed mechanism, not a demonstrated effect of the blend.

What is the recommended dosage of Vinitrox?

The clinically studied dose is Around 500 mg per day, often taken before exercise. Always follow the product label and check with a healthcare provider for personal advice.

Is Vinitrox safe, and does it have side effects?

For most healthy adults, Vinitrox is well tolerated at studied doses. Reported effects can include: Generally well-tolerated — dietary polyphenols are well tolerated. Mild digestive upset is possible at higher intakes. It may also interact with some medications. Vinitrox is not right for everyone, so check with a healthcare provider first if you are pregnant or breastfeeding, have a medical condition, or take prescription medication.

Does Vinitrox interact with any medications?

Possible interactions include: Blood thinners — polyphenols may have a mild additive effect; monitor. Blood pressure medication — possible additive vasodilation; use caution. If you take prescription medication, check with a pharmacist or doctor before using it.

How strong is the scientific evidence for Vinitrox?

NutraSmarts rates the evidence for Vinitrox as Limited (2 out of 5). It is backed by 2 cited references summarized on this page. A higher rating reflects more, larger, and better-designed human studies.

References(2 citations)

Evidence ratings on NutraSmarts are based on the totality of human clinical research, with emphasis on randomized controlled trials, meta-analyses, and systematic reviews. The references below directly support claims made throughout this page.

  1. Deley G, Guillemet D, Allaert FA, Babault N An Acute Dose of Specific Grape and Apple Polyphenols Improves Endurance Performance: A Randomized, Crossover, Double-Blind versus Placebo Controlled Study Nutrients. 2017;9(8):917. doi:10.3390/nu9080917.PubMedUsed to support: Human RCT (n=48 active men, randomized double-blind crossover). An acute 500 mg dose of grape and apple polyphenols (the Vinitrox formulation) increased time to exhaustion by 9.7% versus placebo and delayed the point of maximal perceived exertion. The trial measured endurance and perceived exertion, not nitric oxide or blood flow. Funded by Nexira, the manufacturer, with a Nexira employee among the authors.
  2. Odai T, Terauchi M, Kato K, Hirose A, Miyasaka N Effects of Grape Seed Proanthocyanidin Extract on Vascular Endothelial Function in Participants with Prehypertension: A Randomized, Double-Blind, Placebo-Controlled Study Nutrients. 2019;11(12):2844. doi:10.3390/nu11122844.PubMedUsed to support: Human RCT (n=30, prehypertensive adults aged 40 to 64) of grape SEED proanthocyanidin extract, which is a different product from the Vinitrox grape and apple polyphenol blend. High-dose 400 mg/day for 12 weeks lowered systolic blood pressure by 13 mmHg, but flow-mediated dilation, the direct measure of endothelial (nitric-oxide) function, did not change. This is grape seed extract tested for blood pressure, not Vinitrox tested for blood flow or exercise, so it does not establish a Vinitrox cardiovascular or nitric-oxide benefit.