L-Citrulline: How It Boosts Heart Health and Where to Find It
Nutrition & FitnessDiet & Nutrition

10 Foods High in L-Citrulline for a Healthy Heart

You'll find most of these foods in the melon family.
10 Foods High in L-Citrulline for a Healthy Heart
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Updated on July 31, 2025
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L-citrulline is an amino acid that’s made by your body, but is also present in some foods. Its main health benefit is in boosting the production of nitric oxide. Nitric oxide is a substance that relaxes the muscles in the walls of your blood vessels, improving blood flow and lowering blood pressure.

There’s no set amount of l-citrulline that each person needs every day. But if you’re looking to support your heart health, you might benefit from eating more foods high in l-citrulline. Here are 10 of the top sources.

1. Red Watermelon

When it comes to fruits with the most l-citrulline, watermelon tops the charts. In fact, the name citrulline comes from "citrullus," which is the Latin word for watermelon.

 Red watermelon gets its color from the powerful antioxidant lycopene, which also benefits your cardiovascular health.

2. Yellow Watermelon

Though not as popular as red varieties, watermelon with yellow flesh is another fruit that's a good source of l-citrulline. Like other types of watermelon, it's rich in the antioxidant vitamin C and is very hydrating.

3. Casaba Melons

The casaba melon, a cousin to honeydew, is also a top source of l-citrulline.

 This melon has other nutritional benefits, including providing fiber, potassium, and small amounts of many vitamins and minerals, all with minimal calories and no fat.

4. Cucumbers

Cucumbers have l-citrulline because they're part of the same larger plant family as melons and squash called Cucurbitaceae. Like watermelon, cucumbers are very hydrating and are made up of about 96 percent water.

5. Cantaloupe

In addition to being sweet and juicy, cantaloupe is a good source of the mineral potassium, providing 12 to 16 percent of the recommended daily value in 1 cup.

 Because potassium is also great for supporting blood pressure, the l-citrulline and potassium in cantaloupe may offer even greater heart-health benefits.

6. Mouse Melon

Also called Mexican sour cucumber and cucumelon, this small fruit looks like a miniature striped watermelon. It's a source of l-citrulline but you may have trouble finding it outside of a specialty market.

7. Horned Melon

This type of melon has many names, including spiked melon and kiwano. It is another source of l-citrulline, but the content has been found to be higher in the rind, which you may not want to eat, compared to the flesh.

8. Bitter Melon

Bitter melon, also known as bitter gourd, is another type of melon that contains l-citrulline. The greatest concentration of the amino acid is in the arils, which are the fleshy covering of the seeds.

9. Pumpkin

Though it doesn't contain as much as watermelon, pumpkin is another source of l-citrulline. The orange color is thanks to the plant compound beta-carotene, which is converted into vitamin A and also serves as an antioxidant.

Pumpkins are an excellent source of vitamin A, with 1 cup of the raw gourd providing 55 to 70 percent of the recommended daily value.

10. Summer Squash

All squash are part of the Cucurbitaceae family and a source of l-citrulline, but we don't know the exact amount, and it may vary depending on the variety.

 Still, summer squash such as zucchini and yellow squash are nutritious vegetables that provide fiber along with many important vitamins and minerals.

The Takeaway

  • L-citrulline is an amino acid that helps your body make nitrous oxide — a chemical that improves blood flow and helps lower blood pressure.
  • The best food source of l-citrulline is watermelon, but it’s also in other kinds of melons, cucumbers, and squash.
  • If you’re trying to improve your heart health, ask your doctor whether a supplement might be a good idea.
EDITORIAL SOURCES
Everyday Health follows strict sourcing guidelines to ensure the accuracy of its content, outlined in our editorial policy. We use only trustworthy sources, including peer-reviewed studies, board-certified medical experts, patients with lived experience, and information from top institutions.
Resources
  1. Aguayo E et al. L-Citrulline: A Non-Essential Amino Acid with Important Roles in Human Health. Applied Sciences. April 6, 2021.
  2. Citrulline. PubChem.
  3. Volino-Souza M et al. Current Evidence of Watermelon (Citrullus lanatus) Ingestion on Vascular Health: A Food Science and Technology Perspective. Nutrients. July 15, 2022.
  4. Melons, casaba, raw. U.S. Department of Agriculture. April 1, 2019.
  5. Soak It In: 10 Foods To Help You Stay Hydrated. Cleveland Clinic. May 22, 2025.
  6. Melons, cantaloupe, raw. U.S. Department of Agriculture. April 1, 2019.
  7. Understanding the benefits of potassium. American Heart Association. May 21, 2024.
  8. Mouse Melon or Mexican Sour Cucumber, Melothria scabra. Wisconsin Horticulture.
  9. Hartman J et al. Citrulline and Arginine Content of Taxa of Cucurbitaceae. Horticulturae. March 4, 2019.
  10. Hartman J et al. Citrulline and Arginine Content of Taxa of Cucurbitaceae. Horticulturae. March 4, 2019.
  11. Kane A. The 3 Nutritional Benefits of Pumpkin. Massachusetts General Hospital. October 26, 2023.
  12. Pumpkin, raw. U.S. Department of Agriculture. April 1, 2019.
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Kayli Anderson, RDN

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Kayli Anderson has over a decade of experience in nutrition, culinary education, and lifestyle medicine. She believes that eating well should be simple, pleasurable, and sustainable. Anderson has worked with clients from all walks of life, but she currently specializes in nutrition therapy and lifestyle medicine for women. She’s the founder of PlantBasedMavens.com, a hub for women to get evidence-based, practical, and woman-centered guidance on nutrition and cooking, hormone health, fertility, pregnancy, movement, mental well-being, nontoxic living, and more.

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