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L-Citrulline Explained: Research Doses vs the Vigorus Blend
Quick answer
L-citrulline is an amino acid the body turns into arginine, which is used to make nitric oxide. Studies gave about 3 to 9 grams at a time. In Vigorus, citrulline shares a 570 mg blend with five other ingredients, and its own amount is not published. So one capsule holds well under a single study dose.
What are the citrulline numbers a Vigorus buyer should know?
There are three numbers to keep in mind. Studies used grams of citrulline. The Vigorus blend is 570 mg in total. The label does not publish the citrulline share of that blend.
- 3-9 gcitrulline per dose in the research
- 570 mgwhole Vigorus blend, six ingredients
- Not publishedcitrulline amount per capsule
- 1 capsuledaily serving on the label
Everything below builds on these four figures. If you only read one section, read the blend math further down.
What does L-citrulline do in the body?
Citrulline is an amino acid. Your body makes some on its own, and you also get a little from food such as watermelon.
The main job people care about is a short chain of steps. The kidneys turn citrulline into arginine. Cells then use arginine to make nitric oxide, a signal that tells blood-vessel walls to relax.
Citrulline is absorbed
It passes through the gut and into the blood.
It becomes arginine
The kidneys convert much of it into another amino acid, arginine.
Arginine feeds nitric oxide
Cells lining the blood vessels use arginine to make nitric oxide.
Vessels relax
Nitric oxide signals the smooth muscle in vessel walls to loosen.
Why not just take arginine? Supplement makers often choose citrulline because some arginine is broken down before it reaches the blood. Citrulline takes a longer route that avoids part of that loss.
This pathway is the reason citrulline shows up in circulation formulas. Knowing the pathway, though, does not tell you how much citrulline it takes to matter. That is a dose question.
How much citrulline did the research use?
The research used grams, not milligrams. The NIH Office of Dietary Supplements notes that exercise studies of citrulline gave roughly 3 to 9 grams (NIH ODS).
Those results were not a clean win. A 2022 systematic review and meta-analysis pooled citrulline trials on aerobic exercise. It found no clear benefit for aerobic performance (Viribay et al., 2022).
| Source | What it looked at | Dose range | Takeaway |
|---|---|---|---|
| NIH ODS exercise fact sheet | Citrulline in sports studies | About 3-9 g | Doses are in grams |
| Viribay et al., 2022 | Pooled aerobic exercise trials | Gram-level doses | No clear aerobic benefit |
| Vigorus label | One daily capsule | Share of 570 mg (not published) | Far below study doses |
One more point. These studies tested citrulline on exercise, not on the libido or circulation goals printed on the sales page. So even at full dose, the research does not map neatly onto what Vigorus is marketed for.
How does the 570 mg Vigorus blend compare with a study dose?
The whole blend is smaller than the lowest study dose of citrulline alone. That is the short answer, and the math is simple.
The label lists six ingredients inside one 570 mg blend. Blends usually list ingredients from most to least by weight, so citrulline is likely the largest share. But the label does not say how large.
| Scenario | Citrulline per capsule | Share of a 3 g study dose |
|---|---|---|
| Blend were 100% citrulline | 570 mg | About 19% |
| Citrulline were half the blend | 285 mg | About 10% |
| Six equal parts | 95 mg | About 3% |
To reach 3 grams from a 570 mg blend, you would need more than five capsules a day, and that is only if the blend were pure citrulline. The label says one capsule. Do not stack capsules to chase a study dose.
The fair reading: Vigorus contains citrulline, but not at the amounts that were tested. Read about the other five blend ingredients on the Vigorus ingredients page.
What does the Vigorus sales page say about circulation?
The sales page says the formula is made to support libido, circulation, and healthy testosterone within the normal range. Those are the seller's words, not findings from a trial of this capsule.
Pros
- Citrulline has a real, well-known link to nitric oxide
- Citrulline is listed first, so it is likely the biggest blend share
- The niacin (20 mg) and zinc (11 mg) amounts are printed and sensible
Cons
- The citrulline amount is not published
- The whole blend is under one study dose of citrulline
- No published study tested the finished Vigorus formula
A supplement is not a drug. Vigorus is not meant to diagnose, treat, cure, or prevent any disease. For how the seller describes the formula working, see how Vigorus works.
Is citrulline safe with blood-pressure or nitrate medicine?
Ask a clinician before you start. Citrulline feeds the nitric oxide pathway, and the pine bark in the same blend also touches circulation.
Nitrate drugs work on that same pathway. Many blood-pressure drugs also lower pressure through the blood vessels. Adding more on top is a question for someone who knows your full medicine list.
- Write down every prescription and supplement you take, with doses.
- Bring a photo of the full Supplement Facts panel and the caution text.
- Ask whether the blend could add to your medicine's effect on blood pressure.
- Ask what signs, like dizziness or lightheadedness, should make you stop.
A sexual or erection problem can be an early sign of heart disease or diabetes. A checkup comes before any supplement. The full list of label cautions sits on the side effects page.
How should a buyer weigh citrulline before ordering Vigorus?
Treat citrulline as one small part of a mixed formula, not as a study dose. Then decide whether the rest of the label and the price fit you.
Read the Supplement Facts
Note the two printed doses: niacin 20 mg and zinc 11 mg. Note that the 570 mg blend has no per-ingredient amounts.
Set your expectations
Citrulline here sits far below the 3-9 g used in research. Expect a modest formula, not a study protocol.
Check your medicines
If you take blood-pressure, blood-thinning or nitrate medicine, get a clinician's view first.
Count the days
The guarantee runs 60 days from purchase. The 2-bottle pack covers exactly that window.
Buy from the authorized route
The FDA warns that some men's products hide drugs such as sildenafil (FDA, 2026). Order through a known seller.
Pack prices and the cost per day are on the Vigorus pricing page. The window details are on the guarantee page.
Citrulline in Vigorus: quick questions
What does the label say about citrulline in Vigorus?
It lists L-citrulline first inside a 570 mg proprietary blend. The label does not give the milligrams for citrulline or for any other blend ingredient.
Is 570 mg of citrulline a lot?
The capsule does not hold 570 mg of citrulline. It holds 570 mg of six ingredients combined. Even the full 570 mg would be under the lowest dose of about 3 grams used in the studies we looked at.
Can I add a citrulline powder on top of Vigorus?
Talk to a clinician first. That matters most if you take any blood-pressure medicine or a nitrate, since extra citrulline adds to the same blood-vessel pathway.
Should I take two capsules to get more citrulline?
No. The label says one capsule a day and says not to exceed the dose. Two capsules would also double the niacin to 40 mg, above the 35 mg upper limit for adults.
Does citrulline help with workouts?
The results are mixed. A 2022 review pooled citrulline trials and did not find a clear benefit for aerobic exercise. Vigorus is not sold as a workout product anyway.
Is citrulline the same as arginine?
No, but they are linked. The body turns citrulline into arginine. Arginine is then used to make nitric oxide.
References
- U.S. Food and Drug Administration (2026). Tainted Sexual Enhancement Products.
- NIH Office of Dietary Supplements (accessed 2026). Dietary Supplements for Exercise and Athletic Performance.
- Viribay A, et al. (2022). Effects of Citrulline Supplementation on Different Aerobic Exercise Performance Outcomes: A Systematic Review and Meta-Analysis. Nutrients 14(17):3479.
Ready when you are
Order Vigorus from the authorized outlet
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