L-arginine explained: what it is and food sources
L-arginine is an amino acid found in dietary protein sources such as animal-based foods and nuts. The NIH says it is involved in processing protein, making creatine, and handling urea in the body, which also makes arginine from citrulline, mainly in the kidneys. Three products we reviewed list L-arginine, but none prints its individual amount.
- What it is
- Amino acid
- In the products we reviewed
- 3, none prints the amount
What L-arginine is
- Arginine can come from dietary protein sources such as animal-based foods and nuts.1
- Arginine is an amino acid involved in processing protein, making creatine, and handling urea in the body.1
- Your body also makes arginine from citrulline, mainly in the kidneys.2
- Arginine is used to make nitric oxide, which helps nerve cells communicate and blood vessels widen.1
- Arginine is available as a dietary supplement.1
Foods that have it2
- Animal products
- Nuts
Works with
- Glycine. The liver and kidneys use glycine and arginine to make creatine.1
How much L-arginine each product gives
Amount not printed: the dashed line shows the most it can be, the whole blend
Before you take it
Ask a doctor first
- The safety of taking high-dose arginine supplements for more than 3 months is unknown.2
These statements have not been evaluated by the FDA. A supplement is not a medicine.
The 3 products we reviewed that list L-arginine
| Product | Form and serving | L-arginine per serving | Our score | Price a bottle | Buy |
|---|---|---|---|---|---|
 GlucoTonic#1 in blood sugar support | Liquid drops1 ml | Not printedIn a 200 mg proprietary blend | 9.9 | $49 | Check price |
 Sugar Defender#3 in blood sugar support | Liquid drops1 ml | Not printedIn a 200 mg proprietary blend | 9.5 | $49 | Check price |
 Glyco Harmony#5 in blood sugar support | Liquid drops1 ml | Not printedIn a 200 mg proprietary blend | 9.3 | $49 | Check price |
Questions people ask
What is L-arginine?
L-arginine is an amino acid. The NIH says arginine is involved in processing protein, making creatine, and handling urea in the body.
What does L-arginine do in the body?
Arginine is used to make nitric oxide, which the NIH says helps nerve cells communicate and blood vessels widen.
What foods have L-arginine?
Animal-based foods and nuts are dietary sources of arginine. Arginine can come from the protein in these foods.
How are L-arginine and citrulline connected?
Your body makes arginine from citrulline, mainly in the kidneys.
Is an L-arginine supplement safe?
The safety of taking high-dose arginine supplements for more than 3 months is unknown. Ask a clinician before starting.
Which products we reviewed contain L-arginine, and how much?
GlucoTonic, Sugar Defender, and Glyco Harmony list L-arginine. Each lists it inside a 200 mg proprietary blend, but none prints its individual amount. The 200 mg is the blend amount, not the L-arginine amount.
Also in these products
Sources
The products, amounts and prices come from each product's label and checkout, as its review shows them. AI drafts our pages from listed sources, figures are checked against them, and we have not tried the products.
- 1NIH Office of Dietary Supplements, PrimaryMitochondrialDisorders HealthProfessionalods.od.nih.gov/factsheetschecked
- 2NIH Office of Dietary Supplements, ExerciseAndAthleticPerformance HealthProfessionalods.od.nih.gov/factsheetschecked