Nutricost Nitric Oxide Booster contains 2,250 mg of active ingredients per serving, spread across five different forms of arginine and citrulline. That sounds substantial until you examine the individual amounts and compare them with what researchers have actually studied.
For example, the formula contains just 375 mg of plain citrulline, an amino acid that helps your body produce nitric oxide. Meanwhile, some exercise studies have used several grams of citrulline and found only modest improvements in performance.
That difference matters because nitric oxide helps blood vessels relax and supports normal circulation. Increasing its production might improve certain aspects of exercise performance, but having the right ingredients does not automatically mean a supplement contains enough to produce noticeable results.
Nutricost combines two familiar ingredients in several forms, so the formula deserves a fair examination. In this review, I’ll explain what the doses suggest, how much confidence the manufacturing claims deserve, and whether the product is worth considering.
How I Reviewed Nutricost Nitric Oxide Booster
I didn’t personally take Nutricost Nitric Oxide Booster, and I don’t think that makes this review less useful.
One person’s experience can be interesting, but it tells you surprisingly little about whether a supplement works. Training intensity, expectations, sleep, diet, and ordinary day to day changes can all influence what someone notices.
For that reason, I prefer to look at the formula, compare it with controlled research, examine independent quality records, and then see whether consumer experiences fit what the evidence suggests.
For this review, I:
- Checked the Supplement Facts, ingredient amounts, serving information, and available label records against product documentation.
- Reviewed clinical studies, Nutricost’s manufacturing claims, NSF records, available independent testing information, and FDA recall and warning letter databases.
- Examined consumer feedback and Reddit discussions, separating experiences with this particular supplement from general opinions about Nutricost.
This approach cannot establish how every person will respond, and I didn’t obtain a laboratory report for the product. However, it gives you a stronger basis for judging the formula than relying on a handful of enthusiastic testimonials.
With that in mind, here’s where I stand.
TLDR: My Verdict on Nutricost Nitric Oxide Booster
- Buy it if: You’re an adult who specifically prefers capsules, appreciates a fully disclosed amino acid formula, and understands that the amounts have not been shown to deliver the same benefits seen with larger clinical doses.
- Skip it if: You want a supplement closely aligned with exercise research, need publicly accessible batch testing, or expect substantial improvements in stamina, muscle pumps, or circulation.
My verdict: I would pass on Nutricost Nitric Oxide Booster for exercise performance. The ingredients have legitimate scientific interest, but their relatively small amounts make this particular formula difficult to recommend over better documented options.
The main reason becomes clearer once you separate that impressive sounding 2,250 mg total into its individual ingredients.
What’s Actually Inside Nutricost Nitric Oxide Booster?
I’m reviewing the Nutricost Performance Nitric Oxide Booster with 180 capsules, identified by UPC 810014673318. At three capsules per serving, one bottle contains 60 servings. A 90 capsule package is also available, but this review focuses on the 180 capsule version.
The Supplement Facts, recorded in the National Institutes of Health’s dietary supplement label database, identify five active ingredients per serving.
You get 500 mg of plain L arginine, 500 mg of arginine hydrochloride, and 500 mg of arginine alpha ketoglutarate, also called AKG, in a 2:1 formulation. These ingredients account for 1,500 mg of the advertised total.
The remaining 750 mg comes from 375 mg of plain L citrulline and 375 mg of citrulline malate 2:1. Citrulline malate combines citrulline with malic acid, so its stated weight isn’t entirely citrulline.
I appreciate that Nutricost discloses the amount of each ingredient rather than hiding everything behind a proprietary blend. Still, the total weight includes several different compounds, and it shouldn’t be mistaken for 2,250 mg of pure arginine or citrulline.
The citrulline looks promising, but the amount is modest
Citrulline helps increase arginine availability in your body. Arginine is then used to produce nitric oxide, which signals blood vessels to relax and widen. This is why citrulline often appears in supplements marketed for workout endurance and muscle pumps.
The mechanism is reasonable, but the amount is important.
A 2021 meta analysis examined eight studies involving 137 participants. Researchers found that 6 to 8 grams of citrulline malate taken before strength training improved exercise repetitions by roughly three on average.
That’s a small improvement, not a dramatic transformation. More importantly, the research examined citrulline malate as an ingredient, not Nutricost’s particular supplement, and the studied amounts were considerably higher.
Nutricost provides only 375 mg of citrulline malate alongside 375 mg of plain citrulline. Even combining the listed weights leaves you well below the amounts examined in those trials.
The broader evidence also deserves some caution. In a 2023 clinical trial, 8 grams of plain citrulline did not significantly improve strength, muscular endurance, or muscle oxygenation during the exercises researchers tested.
That doesn’t make citrulline useless. It means the results depend on the exercise, participants, and study design. Examine’s independent citrulline overview is helpful for understanding those differences.
For Nutricost, my concern isn’t simply that some citrulline studies have mixed results. It’s that the product contains much less than the amounts investigated in much of the exercise research.
Arginine makes up most of the formula
Arginine is the other major part of Nutricost’s blend. Your body uses this amino acid to produce nitric oxide, although taking additional arginine doesn’t guarantee a meaningful improvement in exercise performance.
A 2020 systematic review found potential benefits for certain aerobic and anaerobic exercise outcomes. However, the studies used different protocols, and the researchers identified substantially different amounts depending on exercise type and duration.
For context, some protocols involved 1.5 to 2 grams of arginine daily over several weeks, while others investigated considerably larger amounts. These are research protocols, not recommended doses for Nutricost.
There’s another detail here. Nutricost’s 1,500 mg total includes arginine hydrochloride and arginine AKG, meaning that figure isn’t equivalent to 1,500 mg of plain arginine.
AKG combines arginine with alpha ketoglutarate, a compound involved in normal energy metabolism. A 2006 randomized trial reported improvements in some strength and power measures with arginine AKG, but the trial used 12 grams daily, not Nutricost’s 500 mg.
I don’t see convincing evidence that dividing a relatively small amount of arginine among three forms makes it more effective than a simpler formulation.
The formula also contains no listed caffeine, so it isn’t designed to produce the immediate stimulant effect associated with some workout supplements.
What about the inactive ingredients?
The current 180 capsule product information listed by iHerb identifies gelatin capsules, magnesium stearate from a vegetable source, calcium silicate, and silica. These serve manufacturing or capsule functions rather than acting as nitric oxide ingredients.
One detail deserves clarification. The older NIH label record omits calcium silicate, although the currently available retailer information includes it. That difference doesn’t establish a safety problem, but the physical bottle label should take priority if packaging has changed.
Because the capsules contain gelatin, they aren’t suitable for strict vegetarian or vegan diets. Nutricost also describes the product as gluten free and non GMO.
The ingredient list is uncomplicated enough. But the next consideration is whether the contents and manufacturing process have been independently checked.
Is Nutricost Nitric Oxide Booster Clean and Third Party Tested?
Nutricost says its supplements undergo third party testing and are produced in facilities following Good Manufacturing Practices, or GMP. These are manufacturing standards intended to support consistent production, handling, and quality control.
According to Nutricost’s quality statement, its supplements are manufactured in FDA registered, GMP compliant facilities and undergo outside laboratory testing.
There is independent support for part of that claim. NSF’s official listing identifies Nutricost Manufacturing LLC’s facility in Vineyard, Utah, under NSF/ANSI 455-2, a certification covering dietary supplement manufacturing practices.
That’s meaningful evidence about the listed facility. However, facility certification is not the same as independent verification of Nutricost Nitric Oxide Booster itself.
A product certification may involve checking ingredient identity, potency, contaminants, or substances prohibited in sports, depending on the program. A manufacturing certification doesn’t automatically establish that every finished bottle passed those checks.
I couldn’t locate a publicly accessible Certificate of Analysis for this exact booster. A Certificate of Analysis, or COA, is a laboratory document showing the test results for a particular product batch.
I also couldn’t verify an individual product certification in the accessible NSF Certified for Sport, USP Verified, or Labdoor records. ConsumerLab has tested other Nutricost products, but those results shouldn’t be treated as proof that this particular formula passed independent testing.
One additional point deserves attention. Nutricost’s product information displays a California Proposition 65 warning mentioning lead. California’s official guidance explains why such warnings appear on certain food and supplement products.
That warning doesn’t tell us the lead concentration in this product or establish that a specific bottle is unsafe. Without a relevant batch report, however, I can’t independently assess the exposure.
What did the FDA check reveal?
I searched the FDA’s public recall records and warning letters for Nutricost Nitric Oxide Booster, Nutricost, eSupplements, and the relevant manufacturing name.
I didn’t locate a relevant recall or warning letter in the records I could check. That’s reassuring as far as those searches go, although public databases aren’t necessarily exhaustive and the result doesn’t establish that no issue has ever occurred.
So there is credible evidence of manufacturing oversight, but not enough publicly available laboratory information for me to make a stronger product specific purity claim.
That distinction matters when interpreting the positive customer feedback surrounding the brand.
What Do People Actually Say About Nutricost Nitric Oxide Booster?
Consumer feedback on Nutricost’s website and iHerb includes people who describe better workout pumps, improved stamina, and satisfactory value. Some also appreciate the capsule format because it avoids mixing another powder into their routine.
Those are useful observations, although perceived effects don’t establish improvements in nitric oxide production, blood flow, or physical performance. Someone feeling more energetic during training could be responding to several influences beyond the supplement.
The Reddit discussion is particularly limited for this exact formula.
In one Reddit discussion, a commenter specifically reported developing headaches after using Nutricost Nitric Oxide Booster. Another participant mentioned digestive discomfort with Nutricost products, although that comment doesn’t clearly establish which formulation caused it.
A separate brand discussion contains generally favorable experiences with other Nutricost supplements, alongside questions about manufacturing quality and transparency.
Those broader brand comments shouldn’t be mistaken for direct experiences with the nitric oxide formula.
I wouldn’t describe either praise or complaints as a firmly established pattern on Reddit. There’s too little detailed discussion about this exact product to support that conclusion.
Nevertheless, the reported headache is consistent with a known possible effect of arginine. According to Mayo Clinic, arginine supplements may cause headaches, nausea, bloating, abdominal discomfort, or diarrhea.
These reports don’t establish that Nutricost caused a particular reaction. They simply reinforce why individual tolerance and medical circumstances matter when considering a supplement that can influence blood pressure.
Who Should Skip Nutricost Nitric Oxide Booster?
For healthy adults, the main drawback is the limited evidence supporting this particular combination at its labeled amounts. However, there are also circumstances in which avoiding the supplement is a more straightforward decision.
- Anyone under 18: Nutricost specifically labels this formula for healthy adults aged 18 and older.
- People taking certain medications: Arginine may interact with blood pressure medicines, nitrates, sildenafil, blood thinners, and some diabetes medications. Medical advice is important before considering the product.
- People with certain medical conditions: Anyone with low blood pressure, significant cardiovascular concerns, or a recent heart attack should seek professional guidance. Mayo Clinic specifically advises against arginine after a recent heart attack.
- Pregnant or breastfeeding individuals: The manufacturer recommends consulting a healthcare professional, and adequate safety information for this combination is unavailable.
- Anyone avoiding gelatin or requiring verified product testing: The formula contains gelatin, and I couldn’t confirm an accessible batch specific laboratory certificate.
These considerations are particularly important because nitric oxide plays a genuine role in circulation, even when a supplement’s ability to influence it remains uncertain.
Bottom Line: Is Nutricost Nitric Oxide Booster Worth It?
Nutricost Nitric Oxide Booster has some genuine positives. The ingredient amounts are disclosed, the formula avoids added stimulants, and there is independent certification for a Nutricost manufacturing facility.
However, I wouldn’t choose it as my first option for improving workout performance. The biggest issue is the amount of citrulline and arginine relative to the research, followed by limited public access to product specific testing results.
For adults evaluating more focused alternatives, two products have stronger reasons for consideration.
- Kaged Citrulline Powder offers a single-ingredient formula, making the amount of citrulline easier to evaluate against clinical research. The product also has an independently verifiable Informed Sport certification, with published batch testing records.
- Beet It Sport Nitrate 400 takes a different approach, providing 400 mg of dietary nitrate from concentrated beetroot juice. Its Informed Sport listing confirms certification, while a 2025 umbrella review found modest benefits from dietary nitrate for some exercise outcomes, although the evidence quality varied.
Neither alternative guarantees noticeable results, and neither should be treated as a medical solution for circulation problems.
My recommendation is to look beyond the number of ingredients and focus on whether the actual amounts, clinical evidence, and independent testing support the claims.
Before making a decision about Nutricost Nitric Oxide Booster, request a recent batch specific Certificate of Analysis from Nutricost. It would help clarify the product quality questions that publicly available information cannot fully answer.
Medical disclaimer: This article is for informational purposes only and does not replace advice from a qualified healthcare professional. Consult a healthcare professional before considering dietary supplements, especially if you take medication or have a medical condition. Statements about Nutricost Nitric Oxide Booster have not been evaluated by the U.S. Food and Drug Administration. This supplement is not intended to diagnose, treat, cure, or prevent any disease.