L-arginine is an amino acid that plays a key role in your body’s regulation of blood flow because of its ability to increase nitric oxide production. It’s also found in many pre-workout mixes, and it can help enhance both physical and sexual performance.
L-arginine has been used effectively for everything from improving heart function to increasing memory to treating erectile dysfunction. Since the function of pretty much everything in your body depends critically on its blood supply, this is no small matter.
Here’s our research-backed rankings of the ten best L-arginine supplements on the market.
Last updated: January 4, 2023
L-arginine supplements considered: 29
Hours of research: 38
Experts reviewed: 5
Scientific papers referenced: 11
1. L-Arginine PURE
L-Arginine PURE delivers a high dose of L-arginine, and it does so with a highly pure formulation with multiple forms of L-arginine.
Most of its 700 mg of L-arginine per capsule is delivered as arginine alpha-ketoglutarate, but it also includes small amounts of free L-arginine, L-arginine L-pyroglutamate, and L-arginine HCL.
Since these are absorbed through slightly different pathways in your body, this might boost absorption and lead to arginine levels that increase rapidly and stay elevated for a long time.
These features make it great for boosting your sex drive as well as athletic performance, and this versatility earns it our top spot.
2. Havasu Nutrition L-Arginine
Havasu’s L-arginine supplement delivers 400 mg of arginine per capsule, split between L-arginine HCL and L-arginine alpha-ketoglutarate.
In addition, it provides the companion amino acid citrulline, which is also linked to nitric oxide production in the body, and beet root extract, which further enhances nitric oxide production. If you are looking for maximal blood flow, it’s a great solution.
3. BulkSupplements L-Arginine
For the true do it yourselfer, BulkSupplements L-arginine is the way to go. Coming in a pure powdered form of L-arginine HCL (which is what the “base” in the name refers to), this is what you want if you are looking for a way to incorporate L-arginine into your shakes or smoothies.
The downside is shared with all powder-based supplements that are usually taken in low doses: you’ll need a milligram-accurate scale to measure out doses.
4. Jarrow Formulas Arginine-Citrulline Sustain
Jarrow Formulas never goes for flashy supplement formulations, but they do simple formulas quite well. This is the case with their L-arginine supplement, which is a combo of L-arginine and citrulline malate a vegetarian capsule.
It’s certified free of common allergens like gluten, soy, dairy, shellfish, and eggs, making it a good choice for people with food sensitivities and allergies.
5. NOW Double Strength L-Arginine
NOW delivers a heavy dose of L-arginine, with 1000 mg of L-arginine HCL per capsule.
Unfortunately, it’s got a few more binders and stabilizers than purists might like, and another disadvantage is the fact that the L-arginine is supplied in just one form as opposed to multiple different forms.
Still, for those looking for high L-arginine dosages, it’s a good buy.
6. Dorado L-Arginine
Dorado Nutrition makes an L-arginine supplement that is packed with four different forms of L-arginine.
This is nice to see from a bioavailability perspective, but the formulation would benefit more from other nitric oxide boosters, and a higher overall dose (despite the variety of ingredients, each capsule only has 800 mg of L-arginine total).
7. L-Arginine PRO Powder
This powder-based L-arginine supplement is something a little different–it’s almost more of a sports drink than just a supplement. It provides a very high dose (5500 mg) of L-arginine, alongside vitamins C, D, K, and several B-vitamins.
It’s flavored with stevia along with the artificial sweetener xylitol, which some people may not like. The taste and flavoring might make it a little too overpowering to add to a smoothie or a protein shake, which limits its versatility.
8. Goliath by Dr. Emil Arginine Plus
Dr. Emil makes a supplement that provides dual-form L-arginine (both the AKG form and the HCl form), plus citrulline for added nitric oxide power.
However, it’s pretty thick with additives and binders, which puts it below many of the other multi-ingredient arginine-based nitric oxide boosters.
9. Amazing Formulas L-Arginine
At 1000 mg per capsule, Amazing Formulas has a high-potency L-arginine supplement, but aside from that, there is not a whole lot going for this supplement.
With several additional binders, the L-arginine comes only in an L-arginine HCL form. Perhaps better than free L-arginine, but not up to the standards of some of the top ranked supplements.
10. Bestvite L-Arginine
The L-arginine supplement from Bestvite is high dosage and no frills. It comes in the “free” form, which is cheap to manufacture but may not be as readily absorbed by your body as an alpha-ketoglutarate or even an HCL form of L-arginine.
Further, the capsule is stabilized by a lot of binders and fillers, which are a bit of a turn-off. The 1000 mg dosage is the one upside to this L-arginine supplement.
Best L-arginine overall: Pure Label L-Arginine
Delivering a potent and highly bioavailable dose of L-arginine, Pure Label is our overall winner thanks to its clean supplement design and delivery. If you’re looking for the best arginine-only supplement out there, choose Pure Label L-Arginine.
Best L-arginine for erectile dysfunction and sexual performance: Havasu L-Arginine
If you are unhappy with your sexual performance, low levels of nitric oxide might be to blame. Havasu L-Arginine delivers an arginine/citrulline combo that helps boost arousal and erectile function thanks to its multi-ingredient approach to up-regulating your body’s production of nitric oxide.
Best L-arginine for heart health and blood pressure: Pure Label L-Arginine
For heart health, you want to keep things simple: Pure Label L-Arginine delivers over 700 mg of L-arginine per capsule, split across three different forms for maximum absorption. If you’re looking to emulate research that’s used L-arginine to control blood pressure, Pure Label is the way to go.
Best L-arginine for protein shakes: BulkSupplements L-Arginine
Want to add some nitric oxide powder to your custom pre-workout or recovery shake? BulkSupplements is the way to go. You get highly pure L-arginine that you can dial in to the optimal dose, no matter your use case.
Best L-arginine for weight loss: Havasu Nutrition L-Arginine
Havasu Nutrition L-Arginine pairs the nitric oxide boosting capabilities of L-arginine with widely-known nitric oxide boosters found in beet root extract. These ingredients interact to improve your body’s ability to process carbs, which is a huge help when trying to lose weight.
Best L-arginine for boosting nitric oxide: Pure Label L-Arginine
Pule Label includes multiple forms of L-arginine to accelerate your body’s nitric oxide production. It should come as no surprise that our top overall pick is also a great choice for boosting nitric oxide, whether your goals are athletic performance, sexual performance, or long-term health.
Who should buy L-arginine?
L-arginine has three primary uses: improving workout performance and recovery, improving cardiovascular health, and improving sexual wellness, particularly in men. Here’s why:
Improving physical performance. L-arginine helps your body produce nitric oxide, which increases blood supply to your muscles by dilating your blood vessels. In addition, it shifts your carbohydrate metabolism so that your body can replenish muscle glycogen more readily following an intense workout.
Some research suggests that L-arginine can can also increase maximum anaerobic power production and one-rep max, probably by increasing muscular function.
Supporting cardiovascular health. On the health front, L-arginine helps decrease blood pressure by the same nitric oxide upregulation mechanism that boosts performance.
It also helps improve your body’s ability to process carbohydrates, which becomes impaired in metabolic syndrome and in people who are overweight or obese, and is an independent risk factor for heart disease.
Boosting sexual function. Since L-arginine modulates nitric oxide production, it’s also been used successfully as a treatment for erectile dysfunction. Some (though not all) cases of erectile dysfunction can be linked to a deficit of nitric oxide levels, and L-arginine appears to help in these cases.
So, through a few similar mechanisms, L-arginine is useful for people who want to improve their fitness, their athletic performance, and their sexual health.
Additionally, it also can help people who are looking to decrease their risk factors for heart disease.
How we ranked
We examined L-arginine supplements as well as nitric oxide supplements that used L-arginine in a central role alongside other compounds like citrulline to increase nitric oxide levels. Here’s what we evaluated supplements on:
High dosage and effective formulation. When it comes to L-arginine, efficacy and dosage are king.
We looked at both categories because people looking to follow the scientific research as closely as possible likely want pure, unadulterated L-arginine, but people who take a more holistic approach to supplementation may want to take advantage of synergies between L-arginine and other ingredients involved in the synthesis of nitric oxide in the body.
Synergistic ingredients that upregulate nitric oxide pathways. A number of related compounds are used in the biological pathway that L-arginine activates, and supplying these compounds alongside L-arginine may well increase the efficacy of a given dose of L-arginine.
Purity mattered for L-arginine-only supplements. When analyzing pure arginine supplements, we put a high priority on purity.
Any additional ingredients, even binders or bulking agents, detracted from our ratings, and many supplements didn’t even make our list because they were so crowded with unnecessary ingredients.
Streamlined design for synergistic nitric oxide boosters. A clean and streamlined supplement design informed our ratings of the L-arginine based nitric oxide supplements.
We required that the more holistic supplement design not compromise the L-arginine dosage, and dropped anything that didn’t deliver an adequate amount of L-arginine (enough to be effective based on clinical research using L-arginine only).
Evidence-based supporting ingredients. Next, we checked to see if the other ingredients provided alongside L-arginine had strong scientific evidence supporting their efficacy.
If not, we eliminated that supplement from our rankings—a nitric supplement that provides useless ingredients is no better than a basic L-arginine supplement, and is less pure.
The products that made the final cut represent the best of both pure L-arginine products and nitric oxide supplements that provide a hefty and efficacious dose of L-arginine.
Q: What is L-arginine?
A: L-arginine, sometimes also known simply as arginine, is an amino acid that’s used as a building block for many different kinds of proteins in your body.
It can be found in protein-rich foods, both plant and animal-based, and it also plays an important role in regulating your body’s production of nitric oxide.
Nitric oxide increases blood flow and oxygen supply, which explains why L-arginine is a popular pre-workout supplement, but this blood flow benefit also explains L-arginine’s applications for sexual performance and cognitive function.
Q: How should you take L-arginine?
A: L-arginine should be taken at a fairly high dose, between three and eight grams per day depending on your body size.
It’s not clear whether you should take this dosage all at once, or spread it throughout the day—there hasn’t been enough research comparing these different dosing protocols.
If you are looking to boost your recovery after a tough workout, though, you should definitely take your L-arginine dose all at once, and combine it with one gram of carbohydrates per kilogram of body mass (or half a gram of carbs per pound of body weight, roughly).
Q: Is it better to take a pure L-arginine supplement or a blend?
A: Opinions are mixed on the benefits of pure L-arginine versus combo supplements. On one hand, most clinical research has focused on L-arginine alone.
On the other, there are some papers suggesting that L-arginine is most effective when combined with other compounds in the nitric oxide synthesis pathway, like citrulline or other amino acids.
By upregulating your body’s nitric oxide production, L-arginine can lower blood pressure, enhance physical stamina, and improve sexual performance.
Whether it’s beneficial to take L-arginine alongside other nitric oxide boosters like beet supplements remains an open question. Nevertheless, L-arginine is a good bet for both boosting athletic performance and reducing blood pressure.
For BodyNutrition‘s #1 L-arginine recommendation, click here.