Do Amino Acids Boost Nitric Oxide? If you have heard about l-arginine or l-citrulline and their potential for elevating nitric oxide levels, you may have asked yourself that question.

Some amino acids do, in fact, help your body produce nitric oxide, some do not, and some may work for younger people and not as well as you age. Let’s dive into what Aminos help with Nitric Oxide and also what other things they can do.



  • Boosts Nitric Oxide? Yes.
  • Health Benefits: L-Arginine is a precursor to the production of nitric oxide, making it critical for NO synthesis in your body. It also supports protein synthesis, wound healing, and immune function. It works best when combined with L-Citrulline. Together, they provide more of a nitric oxide boost than just one taken alone. There is so much information out there on arginine, it has literally hundreds of thousands of studies. It has been shown to boost nitric oxide time and again.
  • Reference: NIH – Arginine


  • Boosts Nitric Oxide? Yes.
  • Health Benefits: L-Citrulline increases arginine levels in the body, which in turn helps increase NO production. This may seem counterintuitive and begs the question, “Why not just take L-Arginine?”. This is a great question and one that has been addressed by tons of recent research. The choice between L-arginine and L-citrulline isn’t about which one is “better,” but which one might be more effective for specific purposes due to their different metabolic pathways and absorption rates.
    Here are some reasons why L-citrulline is different from L-arginine:
    Better Absorption:
    L-citrulline is absorbed more efficiently in the intestines than L-arginine typically. When you consume L-arginine, a significant portion can be broken down in the liver before it reaches systemic circulation and can be used by your body.  L-citrulline bypasses this extensive first-pass metabolism in the liver, and once it is absorbed, part of it is converted to L-arginine in the kidneys.
    Sustained Increase in Blood Arginine Levels: The conversion of L-citrulline to L-arginine in the kidneys results in a more sustained increase in blood arginine levels compared to consuming L-arginine directly. This prolonged elevation could produce more consistent nitric oxide over time for many individuals.
    Lowered Risk of Gastrointestinal Distress: L-arginine can cause gastrointestinal distress at high doses. This is not the case for equivalent doses of L-citrulline. Some forms of Arginine, however, are easier to digest than others.
    Synergistic Effects with Other Metabolites: L-citrulline is part of the urea cycle, and its metabolism might have added benefits due to the other metabolites in this cycle, like L-ornithine. So again, it still produces L-Arginine in your system, but it has a few extra goodies in it.
    Safety and Tolerability: L-citrulline, especially when derived from natural sources like watermelon, can be a safer and more tolerable option for some people. ( Yup, we use Watermelon in our products! )
    Other Potential Benefits: There’s ongoing research into L-citrulline’s potential advantages beyond just nitric oxide production, including muscle protein synthesis and ammonia detoxification, immunity, and so much more. It may enhance exercise tolerance in people with certain cardiovascular conditions, support the heat, veins, and arteries, and a long list of other potential benefits.
  • Reference: Citrulline and Exercise Performance


  • Boosts Nitric Oxide? No.
  • Health Benefits: L-lysine is vital for protein synthesis, normal hormone production, and calcium absorption. It’s also often used to prevent and treat cold sores (herpes simplex labialis).
  • Reference: NIH – Lysine


  • Boosts Nitric Oxide? Not directly.
  • Health Benefits: Taurine has several functions, including maintaining proper hydration and electrolyte balance in cells, forming bile salts, and supporting the general function of the central nervous system and eyes. Taurine supports heart health by helping to regulate blood pressure and heart rate. It may help reduce the risk of cardiovascular disease by possibly improving the levels of blood lipids and reducing systemic inflammation.
  • Reference: Taurine: A “very essential” amino acid


  • Boosts Nitric Oxide? No.
  • Health Benefits: L-Tyrosine is important for producing neurotransmitters that regulate mood, such as dopamine, norepinephrine, and epinephrine. It is a common ingredient in many nootropic supplements and some energy drinks. These neurotransmitters that L-tyrosine helps produce, especially epinephrine and norepinephrine, are essential for the body’s stress response. During stress, these neurotransmitters are released to potentially help prepare the body to respond, leading to increased heart rate, blood flow to essential organs, and alertness. Proper synthesis and function of these neurotransmitters are critical for an appropriate stress response. Norepinephrine plays a role in constricting blood vessels, which can elevate blood pressure. Individuals with certain conditions that involve an imbalance in neurotransmitter production could benefit from L-tyrosine supplementation to help regulate blood pressure. However, it’s also worth noting that excessive norepinephrine can lead to hypertension, so it’s a delicate balance.
  • Reference: NIH – Tyrosine


  • Boosts Nitric Oxide? No.
  • Health Benefits: Glutamine is the most abundant amino acid in the bloodstream and serves multiple vital functions in the body. L-glutamine supports gut health, immune function, and wound healing. It’s also a vital nutrient for rapidly dividing cells, including those of the gut and immune system. Even though it does not produce nitric oxide, glutamine is incredibly useful for supporting the body’s creation of Glutathione, an essential antioxidant.Glutathione (GSH) is a tripeptide, meaning it is composed of three amino acids: cysteine, glutamate (derived from glutamine), and glycine. The synthesis of glutathione in the body occurs in two main steps:
    1. First Step: The enzyme γ-glutamylcysteine synthetase catalyzes the binding of cysteine to glutamate to form γ-glutamylcysteine. This step is rate-limiting, meaning it’s the slowest step in the synthesis process and often determines the overall rate of glutathione production.
    2. Second Step: The enzyme glutathione synthetase adds glycine to the γ-glutamylcysteine molecule, forming glutathione.
  • Reference: Glutamine: Metabolism and Immune Function, Supplementation and Clinical Translation



  • Boosts Nitric Oxide? No.
  • Health Benefits: Another BCAA, L-Isoleucine is crucial for hemoglobin production and might help with glucose consumption during physical activity.Many products use L-Isoleucine, especially within the sports nutrition and bodybuilding sectors. It’s a common ingredient in protein powders, amino acid supplements, and many recovery drinks. The use of L-Isoleucine, alongside the other BCAAs, is touted for its potential to enhance muscle recovery, reduce muscle soreness, and improve athletic performance in healthy individuals. This stems from BCAAs’ role in muscle protein synthesis and energy production during exercise and has been widely researched.Beyond athletic performance use, L-Isoleucine has several potential health benefits that may be of interest. Firstly, there’s some evidence that it may support blood sugar regulation. L-isoleucine can increase the uptake of glucose into muscle cells and improve glucose metabolism, which can be particularly beneficial after periods of physical activity when muscle cells are more receptive to glucose. By supporting glucose uptake and utilization, L-Isoleucine might play a role in maintaining stable blood sugar levels.L-isoleucine can also promote wound healing. Amino acids are the building blocks of proteins, and proteins, such as collagen, are essential for the repair and regeneration of tissues. Therefore, having an adequate supply of essential amino acids, including L-Isoleucine, can support the body’s natural healing processes.Additionally, as with other amino acids, L-Isoleucine is involved in synthesizing various proteins and enzymes critical for numerous physiological processes. This means that an adequate intake is vital for overall health, ensuring that the body has the necessary components to carry out its daily functions efficiently.While L-isoleucine is popularly recognized for its role in sports nutrition, its impact on health is multifaceted. L-Isoleucine plays an integral role in maintaining health and well-being, from supporting glucose metabolism to promoting tissue repair and being a foundational component for protein synthesis.
  • Reference: Amino Acid Properties and Consequences of Substitutions


  • Boosts Nitric Oxide? No.
  • Health Benefits: As the third BCAA, L-Valine promotes muscle growth and tissue repair. It’s also involved in energy production.
  • Reference: BCAAs and Brain Function


Do Amino Acids Boost Nitric Oxide

Do Amino Acids Boost Nitric Oxide?

The answer is yes; some do, as can be seen above. With Argnine and Citrulline both being important. There are a few important things to note: how to take them, when, and in what ratios.

Do Amino Acids Boost Nitric Oxide when taken in small dosages? Will the typical $29.99 so-called Nitric Oxide booster really produce nitric oxide in my body?

The answer is yes, but the real question is how long do they produce it? Therein lies the issue. Your cheap 1000mg arginine product or 500mg citrulline product will produce nitric oxide in your system for a very short period of time, producing very minimal health or energetic effects. Most studies indicate that around 5 grams of arginine and 2 grams of citrulline are ideal, and they must be taken together for maximum effect. That is roughly a 2:1 ratio.


Where do Amino Acids Come From?

Amino acids used in supplements and for food items and human consumption are typically manufactured via two main methods: extraction from natural sources and bacterial or yeast fermentation. Both methods have their own advantages and special considerations. Let’s explore these methods and address the concerns of purity, cleanliness, and potential contaminants. If you are considering using amino acids, knowing where they come from, how they are made, and safety concerns should help you make a better decision on what kinds to use and from what source.

  1. Extraction from Natural Sources:
    Some amino acids are derived directly from protein-rich natural sources like animal tissues or certain plants. The raw materials used in this process are subjected to something called ‘hydrolysis,’ which is the process of using acid or enzymes to break down the proteins into individual amino acids. After this is complete, various purification processes are performed to obtain the specific amino acids in their purest form.
  2. Bacterial or Yeast Fermentation:
    For many different types of amino acids, especially those that are labeled as vegan or vegetarian, bacterial or yeast fermentation is the primary method of production. Some types of aminos are not yet available via this method.The bacterial and yeast fermentation processes can produce a wide range of amino acids. However, the capability to produce many types of specific amino acids often depends on the microbial strain used and its metabolic pathways. While many amino acids can be synthesized efficiently using this microbial fermentation process, some might be more challenging or possibly less economically viable to produce in this manner compared to extraction or chemical synthesis.Historically speaking, amino acids such as L-methionine, L-phenylalanine, and L-tryptophan have been more challenging to produce in high yields using microbial fermentation. However, today’s advances in metabolic engineering and biotechnology have enabled improved manufacturing and production of these amino acids in recent years.It’s also worth noting that certain specialized amino acids or derivatives, which might be used for very specific health applications or research purposes, might be synthesized using other methods if fermentation isn’t feasible or efficient.Currently, the list of amino acids unavailable via microbial fermentation is continuously shrinking as advances in biotechnology, genetic engineering, and metabolic pathway research enable the modification of microorganisms to produce an ever-expanding array of compounds. If there’s a specific amino acid or set of amino acids you’re curious about, it would be best to look into the current production methods, as they can evolve over time.

    In this method, specific strains of bacteria or yeast that have the ability to produce high yields of the desired amino acid are grown in large fermentation tanks. Once the fermentation process is complete, the amino acid is extracted and purified from the fermentation broth.

Purity and Cleanliness:
Most reputable supplement manufacturers prioritize the purity and cleanliness of their products, but certainly not all, as there are many reports of shady companies with cheap Chinese-made ingredients with no purity testing. After a clean manufacturing facility creates a batch of aminos, the amino acids undergo various purification processes to remove any residual solvents, by-products, or contaminants.


Good Manufacturing Practices (GMP) standards are often followed by quality supplement manufacturers, which ensure that amino acid-based products are produced consistently and meet quality standards. If you want to ensure your amino acids are clean, look for GMP-certified products.

If a product is GMP certified, it normally means the manufacturer has demonstrated a strong regulatory commitment and compliance with international GMP standards such as purity, cleanliness, and transparency.

Potential Contaminants:
Like all manufactured products, there’s a potential for contaminants if quality control measures aren’t stringent. These contaminants could include residual solvents from the extraction process, heavy metals, or impurities from raw materials, in other words, some really nasty stuff! Some low-quality or improperly stored amino acids might also be prone to bacterial or fungal contamination. So, more than just GMP is needed. You should look for products that have been tested and come with what is called a COA.

Consumer Tips:
For consumers, it’s always highly recommended to:

  • Purchase your supplements from reputable brands and sources. Products on Amazon and from companies like WalMart may be of lower quality as they are marketed and priced for low quality and lowest price.
  • Look for third-party testing or certification. This means an independent laboratory has verified the product’s purity and potency.
  • Check for product reviews and feedback. While it’s true most product reviews on websites like Amazon have a huge amount of fake and paid-for information, some reviews may be of value.

In summary, while amino acids manufactured for supplements are generally clean, pure, and safe for consumption, the quality can vary based on the manufacturer and the source. Always do your due diligence and opt for high-quality products to ensure you are getting a safe and effective product.