L-Citrulline is a common pre-workout ingredient for its vasodilating properties. The increased blood flow from L-Citrulline leads to better pumps and improved performance in the gym.
In this article, we’ll be covering the best L-Citrulline supplements available today for boosting performance and increasing pumps. Our top pick is PURE L-CITRULLINE by Transparent Labs, but check out the full list to find which product is right for you.
In a hurry?
In a hurry?
In a hurry and can’t keep reading? How about you check out the Pure L-Citrulline by Transparent Labs.
Pure L-Citrulline by Transparent Labs earns its reputation as a premier choice in the world of supplements, not only due to its top-notch quality and affordability but also because of its stringent third-party certification from Informed Choice, ensuring safety and purity.
Top 7 Best L-Citrulline Supplements Reviewed
1. Pure L-Citrulline by Transparent Labs – Top Pick
Starting our list of L-Citrulline reviews is Pure L-Citrulline from Transparent Labs. Known for delivering some of the highest-quality supplements on the market, let’s see why Transparent Labs’ L-Citrulline takes the top spot on our list.
While Transparent Labs comes in 2g servings, we recommend taking a minimum of 3g at a time to maximize the effects. This leaves you with a solid 80 total servings in each package. With that being said, for optimal effects you’ll want to take closer to 8g at a time, so you may want to consider taking up to 4 servings at once.
Like all of Transparent Labs products, their L-Citrulline is formulated with a simple all-natural formula. The only ingredient you’ll be getting is fermented L-Citrulline with no additional artificial sweeteners, coloring, or preservatives.
Transparent Labs also contains a third-party certification from Informed Choice, which is one of the leading third-party testers for sports supplements. This ensures the products aren't contaminated with any potentially harmful substances.
This is also one of the most affordable products on our list, only costing about $0.23 per serving.
Pure L-Citrulline by Transparent Labs is a standout supplement, celebrated for its quality, affordability at roughly $0.23 per serving, and the peace of mind provided by third-party certification from Informed Choice.
Solid amount of servings per package
Simple, single-ingredient formula
Third-party tested by Informed Choice
Could be better:
2g serving size won’t be enough
Only comes unflavored
2. Nutricost L-Citrulline – Budget Pick
Next on our list is our best budget pick, earning the runner-up spot on our list to Transparent Labs. Let’s see why Nutricost is a great alternative to the top pick on our list.
First, this product comes in a more effective serving size of 3g in each scoop. This makes it easier to ensure you’re getting a minimum effective dose with each scoop. You’re also getting a solid 200 servings in each package. While this is good if you plan on taking L-Citrulline for a long time, it may be too much if you just want to try it out.
Similar to Transparent Labs, this is also a simple, single-ingredient formula with no unnecessary additives.
Photo by @linxreviews
Nutricost’s product is made in a GMP certified facility, ensuring that this product is made at the highest=quality standards for production. It is also quality guaranteed by Nutricost, keeping in-line with their promise to only use the highest-quality ingredients in their products.
As mentioned, this is our best budget pick and is the cheapest product on our list. Each serving is about $0.05 cheaper than Transparent Labs, costing ~$0.17 per scoop. As you’ll see later on in our list, L-Citrulline products can get quite expensive, making this an excellent deal.
Nutricost L-Citrulline is our budget-friendly alternative, securing the runner-up position on our list with its cost-effectiveness, GMP-certified production, and a simple, single-ingredient formula.
Best budget pick
Simple, single-ingredient formula
Minimum effective dose of 3g per serving
Could be better:
High amount of servings per package may not be suitable for those looking to try L-Citrulline for the first time
Only comes unflavored
3. KAGED Citrulline – Best for Pro Athletes
Next up on our list is the third L-Citrulline powder we’ll be covering on our list from Kaged. So, how does this supplement compare to the top 2 spots on our list?
Like Transparent Labs, each serving is only 2g which won’t be ideal to get the effectiveness of this supplement. Taking 1.5 scoops at a time for a total of 3g is the minimum dose you should be taking. This leaves you with 67 total servings per container. Again, ideally you should be getting closer to 8g at a time for optimal effects.
Like the other products covered above on our list, Kaged doesn’t contain any additional filler ingredients.
Photo by @kaged
Kaged also features an Informed Choice guarantee, similar to Transparent Labs. This is specifically an Informed Sport guarantee, making sure each batch is tested for banned substances. While none of the products on our list should contain any banned substances, this added reassurance makes Kaged’s product ideal for athletes who may be subject to testing.
It’s worth noting that this is significantly more expensive than the products above. Each serving is more than twice as much as the equivalent amount of Nutricost, at ~$0.37 per serving.
Kaged Citrulline, our third L-Citrulline powder in focus, provides moderate servings for effectiveness and carries the Informed Sport guarantee, although it comes at a higher price point compared to the previous selections on our list.
Third-party banned substance-tested
No extra unnecessary ingredients
Kaged offers plenty of other single-ingredient products perfect for custom pre-workout blends
Could be better:
Only comes unflavored
One scoop won’t be enough to produce any meaningful effects
Next up is RedCon1’s L-Citrulline supplement, which is another simple, high-quality supplement. Let’s see how it stacks up to the rest of our list.
Like Nutricost, this product comes at the minimum effective dose of 3g of L-Citrulline per serving. You can expect a total of 60 servings per container.
Similar to all other products covered so far, this is a single-ingredient supplement featuring nothing more than L-Citrulline.
Photo by @codynunn13
Unlike the 3 products we’ve covered above, this RedCon1 is the first product on our list not to feature any third-party testing. Especially with products like Nutricost coming at a lower price with these third-party certifications, it’s unclear why Recon1 does not have any.
This is also the most expensive product we’ve featured so far, costing more than twice as much as Transparent Labs. Each serving of RedCon1 will cost you about $0.50.
REDCON1's L-Citrulline is a no-frills, quality supplement with an optimal serving size, although it does not have the benefit of third-party testing and is positioned at a higher price point compared to other alternatives.
Lower servings per package will be suitable for someone looking to try the product out
Could be better:
Only comes unflavored
Doesn’t have any third-party testing certifications
Next on our list is another simple L-Citrulline supplement, this time coming from Nutrabio Labs.
This is one of several products dosed at 2g per serving. Like the others, we recommend a slightly higher minimum dose of 3g total. You can expect a total of 50 servings per container because of this.
Like all the other products we’ve covered so far, this is a single-ingredient supplement.
Similar to Redcon1, Nutrabio also does not feature any third-party certifications. So, if you’re concerned about potential contaminants or quality control during manufacturing, this may not be the best product for you.
While slightly cheaper than the previous entry on our list, this is still one of the more expensive options we’ve covered so far at ~$0.44 per serving.
Nutrabio Labs L-Citrulline maintains its simplicity as a 2g serving supplement, aligning with similar products, but it's worth noting the absence of third-party certifications, and its price point is relatively higher in comparison to some alternatives.
Good amount of servings per container for someone looking to try L-Citrulline
NutraBio offers plenty of other high-quality nutritional supplements you could pair with L-Citrulline
Could be better:
2g serving size is too low to produce meaningful effects
Only comes unflavored
6. Now Foods L-Citrulline – Best for Now Foods Fans
Next on our list is the first capsule-based supplement which may be ideal for those looking for a more convenient way to take L-Citrulline than in a powder. Let’s see how these L-Citrulline pills from NOW Foods compare to the rest of our list.
These pills are fairly small at only 750mg per capsule. This means you’ll need to take 4 capsules at a time to achieve a minimum dose of 3g per serving. This is likely less convenient than a few scoops of powder, especially if you want a higher dose of ~8g at a time. This will leave you with 45 total servings per container.
This is also the first supplement on our list to contain some additional ingredients. On top of L-Citrulline, you can expect 36mg of Calcium in each serving. Of course, these capsules also contain hypromellose to form the actual pill.
NOW Foods is both GMP certified, as well as being UL certified. This goes to show they are committed to producing only the highest-quality supplements. As they proudly state, their products have been tested for stability, potency, and formulation.
Because of the small serving size, this is one of the more expensive options on our list. Each serving of 4 pills will cost you around $0.68.
NOW Foods L-Citrulline provides capsules for convenience, but the smaller size may require taking four for an effective dose, and it includes added ingredients, making it relatively higher-priced.
Only capsule-based supplement on our list
Contains some added calcium
No other unnecessary ingredients
Could be better:
Small amount of L-Citrulline per pill
Pills will be more difficult to take than powder for some
Closing off our list is Beyond Raw’s “Lab Grade” L-Citrulline. Being the most expensive product on our list by far, let’s see if there’s anything special here that justifies the price.
This product is dosed effectively at 3g per serving. It also has the lowest amount of servings per container by far with only 30.
Like all the other powders on our list, the only listed ingredient here is L-Citrulline.
Photo by @beyondrawlabs
The final product on our list, similar to Redcon1 and Nutrabio, also doesn’t have any third-party certifications. Considering that this is easily the most expensive product on our list, it’s hard to justify not featuring any certification to ensure a high-quality product.
As mentioned, this is the most expensive product on our list by far, costing nearly a dollar per serving at ~$0.83 per scoop. With products like Nutricost being a small fraction of this cost, it’s difficult to justify such a high price for a basic L-Citrulline supplement.
Transparent Labs Mass Gainer combines grass-fed whey protein with organic tapioca maltodextrin for ample protein and complex carbs in chocolate or vanilla flavors, maintaining a natural ingredient profile and affordable pricing.
Small amount of servings per container may be good for trying the product out
Could be better:
Most expensive product on our list
Only comes unflavored
What Is L-Citrulline and What Are Its Benefits?
L-Citrulline is a non-essential amino acid most commonly found in watermelons. It is a potent vasodilator making it a popular pre-workout ingredient. As shown by the supplements above, it can also be taken on its own to receive all the benefits at a more affordable price. So, how does L-Citrulline work?
The science behind vasodilation, or increased blood flow, involves raising Nitric Oxide (NO) levels in the bloodstream. NO levels are largely boosted by Arginine. While you may think direct supplementation with Arginine would be best for this, it turns out L-Citrulline is much better.
This is because supplemented Arginine is largely catobolized by intestinal bacteria and arginases or metabolized by the liver. As a result, very little is actually used in the bloodstream as a substrate for NO. This means it won’t have a major effect on performance.
Meanwhile, L-Citrulline is a precursor to L-Arginine in the bloodstream and is more effective at raising NO levels. This leads to a more potent vasodilatory effect, leading to increased performance when taken correctly.
The benefits of increased NO levels caused by L-Citrulline supplementation are better pumps, as well as reduced fatigue, and improved recovery. While most of these benefits are found in acute doses, it’s worth noting that benefits to endurance are largely seen with more consistent use.
Overall, vasodilation caused by L-Citrulline makes it a potent ingredient for improving multiple performance parameters. This is why it’s so common in pre-workout formulas and as a standalone sports supplement.
How to Choose the Best L-Citrulline Supplement?
It’s worth noting that most basic L-Citrulline supplements are very similar. While Citrulline Malate is slightly different as we’ll cover more in-depth later on, pure L-Citrulline supplements mostly contain the same single-ingredient formula.
However, there are a few things to look out for when choosing an L-Citrulline supplement. These include form, servings, cost, certification, price, and other ingredients, which we’ll be covering in more detail down below.
1. Decide Between L-Citrulline and Citrulline Malate
While the supplements covered on this list were all pure L-Citrulline, this supplement is commonly sold as Citrulline Malate. While these are effectively the same supplement, Citrulline Malate is a slightly different formula that requires higher dosing. It may also be better for boosting performance because of Malate’s role in ATP production.
If you’re interested in learning more about the difference between these products, we’ve covered them in more depth down below.
2. Look at the Number of Servings per Package
First, consider how many servings you want to buy at once. The packages on our list range from 30-200 servings. While more servings may be better for someone planning on taking L-Citrulline for a long time, someone just looking to try the supplement out may want fewer servings.
It’s worth noting that the listed serving size is often too low for optimal results. For L-Citrulline to be most effective, you’ll want to take it at a dosage of anywhere from 3g-10g for optimal effectiveness.
Keep in mind that larger packages will usually have a lower cost per serving than smaller ones. So, if you’re ok with spending a bit more upfront you’ll be saving money in the long run.
3. Choose the Best Price per Serving
Because L-Citrulline is typically sold as a basic single-ingredient supplement, there’s not much of a reason to buy a more expensive supplement compared to a cheaper option. While there is a fairly wide range in price points, all these supplements will deliver very similar effects. Because of this, we recommend opting for a cheaper option.
4. Consider Certification From a Recognized Third Party
Whenever looking for supplements, buying a product with a third-party certification is always a good idea. This will ensure the product doesn’t contain any contaminants or potential banned substances. Because most supplements are not regulated by the FDA, finding products with extra third-party certifications is always a good idea.
One specific label to look for is a CGMP certification, which ensures the product is made with current good manufacturing practices. Other trustworthy methods of certification include Informed Choice and UL. An Informed Sport supplement is a good way to make sure a supplement doesn’t contain any banned substances, which may be necessary if you’re a pro athlete.
Keep in mind that there are several products on our list that don’t contain any third-party certification. If you’re especially concerned about banned substances, contaminants, or quality control during manufacturing, consider choosing products with trustworthy certifications.
5. Consider Capsules vs. Powder
Finally, consider which form you want to take your L-Citrulline in. As you can see from our list, powders are much more common than capsules. However, with products like NOW Foods, you can still find L-Citrulline in capsule form. They’re the same product at the end of the day, so just go for whichever seems more convenient to you!
6. Consider Taking It as Part of a Pre-workout
While we focused on pure L-Citrulline supplements in this list, it is very commonly taken as part of a pre-workout supplement. While you can take a pre-made pre-workout blend, you can also make a custom mixture by combining L-Citrulline with other powerful ergogenic ingredients.
Consider mixing L-Citrulline with Beta-Alanine, Betaine, and Caffeine for a powerful pre-workout blend. These are all some of the most effective and research-backed ingredients available, and make for an excellent pre-workout supplement when combined.
It’s worth mentioning that all the products on our list are completely unflavored. So, if you’re interested in taking L-Citrulline as part of a flavored supplement, going for a pre-mixed pre-workout drink may be the way to go.
What Is the Best Way to Take L-Citrulline?
Once you’ve decided on which L-Citrulline supplement to take, there are a few tips you’ll want to keep in mind. These include dose, timing, and how regularly to take the supplement! We’ll be covering each of these points in more depth below.
Tip #1. Take at Least 3 Grams
While the amounts of L-Citrulline administered vary across studies, it appears the minimum amount of L-Citrulline for effects on exercise is 3g. Higher doses of up to 10g may even be beneficial for improving exercise performance.
L-Citrulline is commonly taken in the form of Citrulline Malate as well, which should be taken at a slightly higher dose of 6g+. We’ll be going more in-depth on the difference between L-Citrulline and Citrulline Malate below.
Tip #2. Take It ~60 Minutes Before Exercising
By taking L-Citrulline around an hour before exercising, you’re giving the necessary reactions plenty of time to take place in your body. This will ensure that NO levels in your blood will be higher during your workout, which will maximize all the associated benefits. If you take Citrulline too early or too late, you won’t get the optimal effects from this supplement during your workout.
Tip #3. Use It for at Least 7 Consecutive Days
While most studies look at the acute effects of L-Citrulline, it appears it may be beneficial to take the supplement consistently as well. One study that examined the effects of L-Citrulline supplementation for 7 consecutive days found that it specifically improved endurance performance in young healthy adults. So, if you’re looking to take L-Citrulline for endurance purposes, consider taking it every day for at least a week.
What Is the Difference Between Citrulline and Citrulline Malate?
While all the supplements on our list are pure L-Citrulline, this supplement is commonly sold in the form of Citrulline Malate. Many pre-workout formulas contain Citrulline Malate instead of L-Citrulline, and many studies use Citrulline Malate as well. So, what’s the difference?
It’s worth noting that Citrulline Malate contains a lower amount of L-Citrulline by weight. This means more Citrulline Malate needs to be taken to get the same effects as pure L-Citrulline. You need to take roughly twice as much Citrulline Malate to get the same effects as pure L-Citrulline. So, while L-Citrulline should be dosed at a minimum of 3g, Citrulline Malate should be dosed around 6g at a minimum.
Overall, these are the same basic supplements and will deliver nearly identical effects with proper doses. This makes it difficult to say which is the best form of L-Citrulline. You may be interested in taking a Citrulline Malate supplement if you’re looking for the added benefits of ATP, just keep in mind you will need to take slightly more.
We decided to focus primarily on L-Citrulline on this list, but if you’re interested in the best Citrulline Malate supplement, we recommend checking out MyProtein’s 100% Citrulline Malate Powder.
Is It Ok to Take L-Citrulline Every Day?
Yes, there do not appear to be any dangers associated with daily use of L-Citrulline. Consistent daily supplementation is associated with improved endurance exercise performance. While most people will only take L-Citrulline before working out for the acute effects, taking the supplement consistently may be more beneficial for endurance athletes.
Does L-Citrulline Really Work?
Yes, L-Citrulline is one of the best ingredients for raising NO levels in the blood, and will likely improve blood flow leading to better pumps and improved exercise performance. While improvements to performance may be somewhat minor, L-Citrulline will still provide a boost to blood flow.
Which Is Better for Nitric Oxide L-Citrulline or L-Arginine?
Although increased Arginine levels in the blood are what’s responsible for better Nitric Oxide, Arginine supplementation is not directly as effective at stimulating this effect. Oddly enough, L-Citrulline is much better at raising plasma Arginine levels, which then leads to increased NO. This makes L-Citrulline the superior supplement for Nitric Oxide.
L-Citrulline is one of the most common vasodilators available, and its NO-boosting properties are related to increases in performance. While it’s commonly taken as part of a pre-workout, it can also be taken on its own as a powder or in capsule form. While most people will take L-Citrulline for its acute effects, chronic supplementation has been shown to increase exercise endurance.
If you’re looking for the best basic L-Citrulline supplement available, we recommend checking out PURE L-CITRULLINE by Transparent Labs. If you’re looking for a capsule-based supplement instead, check out NOW Foods L-Citrulline, just keep in mind it will be more expensive.
Have you taken L-Citrulline before or are you looking to try it for the first time? Do you take any other supplements as a part of your pre-workout stack? Let us know your thoughts in the comments below!
1. "Clean Living starts with an Informed Choice" Informed Choice https://choice.wetestyoutrust.com/ (accessed October 15, 2023).
2. "Facts About the Current Good Manufacturing Practices (CGMP)" U.S. Food and Drug Administration May 31, 2023
3. "Certification" https://www.ul.com/services/certification (accessed October 15, 2023).
4. Rauúl Besco, Antoni Sureda, Josep A. Tur & Antoni Pons "The Effect of Nitric-Oxide-Related Supplements on Human Performance" Sports Medicine volume 42, pages99–117 (2012)
5. Gonzalez, Adam M.,Trexler, Eric T. "Effects of Citrulline Supplementation on Exercise Performance in Humans: A Review of the Current Literature" Journal of Strength and Conditioning Research 34(5):p 1480-1495, May 2020.
6. Stephen J. "l-Citrulline supplementation improves O2 uptake kinetics and high-intensity exercise performance in humans" Journal of applied physiology 15 Aug 2015
7. D Bendahan1, J P Mattei, B Ghattas, S Confort-Gouny, M E Le Guern, P J Cozzone "Citrulline/malate promotes aerobic energy production in human exercising muscle" British Journal of Sports Medicine
8. Lewis A. Gough "A critical review of citrulline malate supplementation and exercise performance" Springer Link 21 August 2021
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