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Support peak performance with this duo from Source Naturals. L-Arginine and L-Citrulline Complex features two amino acids bundled into a single powerful supplement. L-Arginine is an important factor in muscle metabolism and is a precursor for nitric oxide, which promotes healthy circulation by relaxing blood vessels. L-Citrulline helps the body rid itself of ammonia, a by-product of exercise. This clearing enables the body to recover after a workout.

Contains no yeast, dairy, egg, gluten, soy or wheat. Contains no sugar, starch, salt, preservatives, or artificial color, flavor or fragrance.

For a great aid in metabolism and exercise, try Source Naturals L-Arginine L-Citrulline Complex! L-Arginine is a precursor to nitric oxide, helping the body metabolize muscle and increase circulation by relaxing blood vessels. L-Citrulline enables the body to recover after a workout due to clearing it of ammonia, a byproduct of exercise.

Contains no yeast, dairy, egg, gluten, soy or wheat. Contains no sugar, starch, salt, preservatives, or artificial color, flavor or fragrance.

Source Naturals L-Arginine L-Citrulline Complex delivers two amino acids bundled into a single powerful supplement. L-Arginine is an important factor in muscle metabolism and is a precursor for nitric oxide, which promotes increased circulation by relaxing blood vessels. L-Citrulline helps the body rid itself of ammonia, a by-product of exercise. This clearing enables the body to recover after a workout.

Contains no yeast, dairy, egg, gluten, soy or wheat. Contains no sugar, starch, salt, preservatives, or artificial color, flavor or fragrance.

Citrulline is a non-essential amino acid that is an important intermediate in the urea cycle that functions alongside the other amino acids to rid the body of ammonia, a byproduct of protein metabolism. Citrulline also plays an important role in the healing process and in the maintenance of a healthy immune system.

Citrulline is a non-essential amino acid that is an important intermediate in the urea cycle, functioning along with Arginine and Ornithine to rid the body of ammonia, a byproduct of protein metabolism. Because Citrulline is a precursor of Arginine, it provides a readily available source material for Arginine production, which in turn, can be used for the production of Nitric Oxide (NO). NO plays a fundamental role in vascular function and blood flow. Citrulline therefore, not only supports detoxification pathways, but also supports NO production and a healthy cardiovascular system. Not manufactured with wheat, gluten, soy, milk, egg, fish, shellfish or tree nut ingredients.

Support muscle growth and recovery with Swanson L-Glutamine. Glutamine is the most abundant free amino acid found in the muscles of the body. It may also minimize muscle breakdown and improve protein metabolism. Supporting muscle health and strength promotes joint comfort which is key to mobility and healthy aging.

A versatile amino acid, glutamine may also benefit cognitive function and brain health. It is able to cross the blood-brain barrier and acts as a precursor to important neurotransmitters such as glutamate, aspartate and GABA.

Glutamine also provides fuel for immune cells through its activity in the gut where it may help maintain intestinal barrier function to promote GI tract integrity. Since a solid 70% of your immune system stems from your gut, keeping your digestive system happy is a win for your immune function as well.

Glutamine aids in the production of glutathione, often called the “master antioxidant.” Antioxidants help the body combat oxidative stress caused by free radicals which can in turn support the health of cells and bodily systems as we age.

Support muscle growth and recovery with Swanson L-Glutamine. Glutamine is the most abundant free amino acid found in the muscles of the body. It may also minimize muscle breakdown and improve protein metabolism. Supporting muscle health and strength promotes joint comfort which is key to mobility and healthy aging.

A versatile amino acid, glutamine may also benefit cognitive function and brain health. It is able to cross the blood-brain barrier and acts as a precursor to important neurotransmitters such as glutamate, aspartate and GABA.

Glutamine also provides fuel for immune cells through its activity in the gut where it may help maintain intestinal barrier function to promote GI tract integrity. Since a solid 70% of your immune system stems from your gut, keeping your digestive system happy is a win for your immune function as well.

Glutamine aids in the production of glutathione, often called the “master antioxidant.” Antioxidants help the body combat oxidative stress caused by free radicals which can in turn support the health of cells and bodily systems as we age.

Glutamine is involved in maintaining a positive nitrogen balance (an anabolic state) and also aids rapidly growing cells (immune system lymphocytes and intestinal cell enterocytes). Glutamine has recently been the focus of much scientific interest. A growing body of evidence suggests that during certain stressful times, the body may require more glutamine than it can produce. Under these circumstances, glutamine may be considered a "conditionally essential" amino acid. In addition, glutamine is a regulator of acid-base balance and a nitrogen transporter.

Stock up on NOW®'s L-Glutamine Powder today! Glutamine has recently been the focus of much scientific interest. A growing body of evidence suggests that during certain stressful times, the body may require more glutamine than it can produce. Under these circumstances, glutamine may be considered a "conditionally essential" amino acid. Glutamine is involved in maintaining a positive nitrogen balance (an anabolic state) and also aids rapidly growing cells (immune system lymphocytes and intestinal cell enterocytes). In addition, glutamine is a regulator of acid-base balance and a nitrogen transporter.

Try NOW® Sports L-Glutamine Powder today! Glutamine has recently been the focus of much scientific interest. A growing body of evidence suggests that during certain stressful times, the body may require more glutamine than it can produce. Under these circumstances, glutamine may be considered a "conditionally essential" amino acid. Glutamine is involved in maintaining a positive nitrogen balance (an anabolic state) and also aids rapidly growing cells (immune system lymphocytes and intestinal cell enterocytes). In addition, glutamine is a regulator of acid-base balance and a nitrogen transporter.

You know watermelon is a tasty summertime treat, but did you know it’s also one of nature’s best sources of citrulline? Unfortunately you’d have to eat several pounds of watermelon every day to reap the benefits. Just what is citrulline though? It's bursting onto the fitness scene in a big way, helping people of all ages break through the boundaries of personal health and fitness. L-citrulline is active in both the Krebs cycle and the Urea cycle of metabolism, which means it promotes energy production to fuel activity while simultaneously helping to rid the body of metabolic waste products, helping to promote muscle recovery after exercise¹. The addition of malate, a form of malic acid, further bolsters the bioavailability of L-citrulline.

L-citrulline is an amino acid precursor to—and more efficiently absorbed by the body than—arginine which in turn produces nitric oxide. Nitric oxide works to deliver oxygen and other nutrients throughout the body to feed muscles and tissues. This is especially beneficial during high-intensity exercise, and may also help maintain blood pressure already within the normal range², support men’s sexual health², and encourage active aging by promoting cardiometabolic health in older adults³.

Sources

1. Farney, T, et al., Journal of Strength and Conditioning Research 33(9):p 2464-2470, September 2019. | Read more.
2. Neri, L. Examine.com, accessed 10 June 2025
3. Allerton TD, et al. Nutrients. 2018 Jul 19;10(7):921. Read more.

Move over creatine! Swanson® L-Citrulline Malate Complex is the energizing combination that kicks in beyond the Krebs cycle. It's bursting onto the nutrition scene in a big way, helping people young and old break through the boundaries of physical health, energy and performance. L-Citrulline Malate is active in both the Krebs cycle and the urea cycle of metabolism, which means it promotes energy production while simultaneously helping to rid the body of fatigue-causing metabolic waste products.

L-Citrulline is a unique amino acid first isolated from watermelon and produced in the body from the amino acids ornithine and arginine. It's a key player in the urea cycle, which is the process responsible for eliminating the metabolic by-products of protein metabolism. These by-products, primarily ammonia and lactic acid, contribute to muscle fatigue. By helping to efficiently remove them, L-citrulline helps fend off fatigue for greater comfort and endurance. L-citrulline also acts as a precursor to nitric oxide, a compound that helps relax blood vessels to promote healthy circulation and ensure a steady supply of oxygen and nutrients throughout the body.

Malic acid is an organic compound made by all living organisms. It performs a vital function in cellular energy production as an intermediary in the Krebs cycle (also known as the citric-acid cycle), the metabolic pathway that produces ATP (adenosine triphosphate), the primary energy source for every cell in the body.

The dual-action effects on energy production and waste elimination make our L-Citrulline Malate Complex the perfect nutritional boost for physical comfort and endurance.

NOW Foods' L-Citrulline Powder not only supports detoxification pathways, but also supports nitric oxide production and a healthy cardiovascular system. Citrulline is a non-essential amino acid that is an important intermediate in the urea cycle, functioning along with Arginine and Ornithine to rid the body of ammonia, a byproduct of protein metabolism. Because Citrulline is a precursor of Arginine, it provides a readily available source material for Arginine production, which in turn, can be used for the production of Nitric Oxide (NO). NO plays a fundamental role in vascular function and blood flow.

NOW Foods' L-Glutamine features 500 mg per capsule. Glutamine has recently been the focus of much scientific interest. A growing body of evidence suggests that during certain stressful times, the body may require more glutamine than it can produce. Under these circumstances glutamine may be considered a "conditionally essential" amino acid. Glutamine is involved in maintaining a positive nitrogen balance (an anabolic state) and also aids rapidly growing cells (immune system lymphocytes and intestinal cell enterocytes). In addition, glutamine is a regulator of acid-base balance and a nitrogen transporter. 

Glutamine has recently been the focus of much scientific interest. A growing body of evidence suggests that during certain stressful times, the body may require more glutamine than it can produce. Under these circumstances, glutamine may be considered a "conditionally essential" amino acid. Glutamine is involved in maintaining a positive nitrogen balance (an anabolic state) and also aids rapidly growing cells (immune system lymphocytes and intestinal cell enterocytes). In addition, glutamine is a regulator of acid-base balance and a nitrogen transporter.