Nutrition Diet: What food is highest in nitric oxide? A Guide to Boosting Your Levels

October 3, 2025 •

4 min read

Studies have consistently shown that consuming nitrate-rich foods can significantly elevate the body's nitric oxide (NO) levels, a crucial signaling molecule for cardiovascular health. A common question is, what food is highest in nitric oxide? This article explores the top dietary sources and mechanisms to help you increase your body's natural production.

Quick Summary

This guide details the highest sources of nitric oxide precursors, including nitrate-rich vegetables, citrulline, and arginine. It explains the biological pathways and benefits, differentiating natural sources from processed additives, and provides a comprehensive food comparison.

Key Points

Leafy Greens Reign Supreme: Arugula, spinach, and celery are among the richest dietary sources of nitrates, a key precursor to nitric oxide.
Beets Provide Rapid Boosts: Both beetroot and beetroot juice can significantly and quickly increase nitric oxide levels in the body, which aids athletic performance.
Watermelon is a Citrulline Powerhouse: This fruit contains abundant L-citrulline, an amino acid that the body converts into L-arginine, an important precursor for nitric oxide synthesis.
Antioxidants Stabilize Nitric Oxide: Foods like dark chocolate, citrus fruits, and pomegranates contain antioxidants that protect nitric oxide from degradation, maximizing its bioavailability.
Natural vs. Processed Nitrates: The nitrates in vegetables are safe and beneficial, while those added to processed meats can lead to harmful compounds, making whole foods the healthier choice.
Exercise and Lifestyle Factors Matter: Combining a healthy diet with regular exercise and stress management is an effective strategy for naturally increasing nitric oxide production.

Nitric oxide (NO) is a simple, yet vital, molecule produced naturally within the human body. Its primary function is vasodilation, which means it relaxes the inner muscles of blood vessels, causing them to widen and increase blood flow. This process has a ripple effect on overall health, impacting everything from blood pressure and brain function to exercise performance. The good news is you can influence your body's NO production significantly through diet.

The Pathways to Nitric Oxide Production

There are two primary ways the body produces nitric oxide from the foods you eat:

The Nitrate-Nitrite-Nitric Oxide Pathway

This pathway starts with nitrate-rich vegetables. After you consume these foods, nitrates are absorbed into the bloodstream. Some are then concentrated in your salivary glands. Oral bacteria convert this nitrate into nitrite. When swallowed, the nitrite reacts with the acid in the stomach and is further converted into nitric oxide, which is then released into the bloodstream. This pathway is especially important during low-oxygen conditions, like intense exercise.

The L-Arginine-Nitric Oxide Synthase Pathway

Another method uses the amino acid L-arginine. The enzyme nitric oxide synthase (NOS) converts L-arginine into nitric oxide. While L-arginine is readily available in many high-protein foods, its bioavailability is sometimes limited due to metabolism. This is where L-citrulline, another amino acid, comes in. Found abundantly in watermelon, L-citrulline is converted into L-arginine in the kidneys, which can then be used to produce NO more efficiently than consuming L-arginine directly.

The Top Tier: Foods Highest in Nitric Oxide Precursors

For those asking what food is highest in nitric oxide?, the answer is not a single item but a category of nutrient-dense powerhouses. Arugula and other leafy greens are consistently cited as having exceptionally high nitrate content.

Highest in Nitrates:

Arugula: Often considered the king of nitrates, arugula is packed with compounds that the body converts into NO.
Spinach: Fresh spinach contains a very high concentration of nitrates, with studies showing significant increases in NO levels after consumption.
Beetroot: This root vegetable and its juice are famous for boosting NO. One study found that subjects drinking beet juice saw a 21% increase in blood NO levels within 45 minutes.
Celery: Another standout, celery boasts very high nitrate levels.

Highest in Citrulline:

Watermelon: Watermelon is an excellent source of L-citrulline, which the body converts into L-arginine, effectively boosting NO production.

Highest in Arginine:

Pumpkin Seeds: These seeds are among the richest sources of L-arginine, making them an excellent choice for supporting NO synthesis.
Poultry and Meat: Turkey, chicken, and other meats are also high in L-arginine.

A Comprehensive List of Nitric Oxide Boosting Foods

To ensure a consistent supply of NO-boosting nutrients, incorporate a diverse range of these foods into your diet. This goes beyond the highest-ranking foods to create a more balanced intake.

Nitrate-Rich Vegetables: Kale, Swiss Chard, Carrots, Broccoli, Cabbage, and Fennel.
Antioxidant-Rich Fruits: Pomegranate, Citrus Fruits (Oranges, Grapefruits, Lemons), Berries, and Grapes. Antioxidants protect NO from breakdown, preserving its effects.
Nuts and Seeds: Walnuts, Almonds, Pistachios, and Sunflower seeds all contain L-arginine.
Garlic: While not high in nitrates, garlic contains allicin, a compound that helps activate nitric oxide synthase (NOS).
Dark Chocolate (70%+): The flavanols in dark chocolate help protect NO levels and improve vascular health.

Comparison of Nitric Oxide Boosting Foods


Food Type	Primary Booster	Key Examples	Benefits
Leafy Greens	Nitrates	Arugula, Spinach, Kale	Most concentrated nitrate source, major cardiovascular benefits.
Beets	Nitrates	Beetroot, Beet Juice	Potent and rapid increase in NO levels, proven for athletic performance.
Citrulline Fruits	L-Citrulline	Watermelon, Cucumbers	Converted to L-arginine for efficient NO production, boosts blood flow.
Arginine Proteins	L-Arginine	Pumpkin Seeds, Poultry, Nuts	Provides raw material for the NOS pathway, supports muscle and vascular health.
Antioxidant Foods	Antioxidants (Flavanols, Vitamin C)	Dark Chocolate, Pomegranate, Citrus	Protects and stabilizes existing NO, boosts bioavailability.

The Healthy vs. Unhealthy Nitrate Distinction

It is critical to distinguish between the naturally occurring nitrates in vegetables and the sodium nitrite/nitrate additives used in processed meats like bacon and deli meats. While both contribute to NO, the context is vastly different. Vegetables contain high levels of beneficial antioxidants like Vitamin C, which prevent nitrates from forming harmful nitrosamines. Processed meats, on the other hand, lack these protective antioxidants, and their added nitrites, especially when exposed to high heat, can form carcinogenic nitrosamines. Therefore, for a healthy diet, focus on natural, plant-based sources of nitrates and limit your intake of processed meats.

Beyond Food: Other Lifestyle Boosters

Diet is a powerful tool, but other lifestyle factors can amplify your body’s nitric oxide production:

Regular Exercise: Physical activity, especially cardio and high-intensity interval training (HIIT), stimulates the endothelial cells lining your blood vessels to produce more nitric oxide. This improves circulation and vascular health.
Limit Mouthwash: The beneficial oral bacteria that convert nitrate to nitrite are often killed by antimicrobial mouthwash. This can negatively impact the nitrate-to-NO pathway, so consider moderating mouthwash use.
Manage Stress: Chronic stress can impair NO production. Practices like meditation, deep breathing, and yoga can help manage stress and support healthy NO levels.

Conclusion

To optimize your body's nitric oxide levels, the most effective strategy is a diverse diet rich in plant-based foods. While arugula, spinach, beets, and watermelon are standout sources of specific NO precursors like nitrates and citrulline, a balanced approach incorporating nuts, seeds, and antioxidant-rich fruits and dark chocolate provides the most comprehensive benefits. By focusing on these whole food sources and supporting them with a healthy lifestyle including regular exercise, you can naturally enhance your vascular health and overall well-being.

For more in-depth information on the physiological roles of nitric oxide, you can explore research from the National Institutes of Health.

Frequently Asked Questions

Nitric oxide (NO) is a gas molecule that acts as a signaling agent in the body. Its primary role is to relax and widen blood vessels, which improves circulation, lowers blood pressure, and ensures organs receive sufficient oxygen and nutrients.

Studies have shown that consuming beetroot juice can increase nitric oxide levels in the blood within as little as 45 minutes. This rapid effect is why it is often used by athletes to boost performance.

No, the nitrates are not the same. While both contain nitrates, vegetables also contain high levels of antioxidants that prevent the formation of harmful nitrosamines. Processed meats lack these antioxidants, and the added nitrites can form carcinogenic compounds, making them unhealthy.

Yes. Many nuts and seeds are rich in L-arginine, an amino acid that serves as a building block for nitric oxide production in the body. Good examples include pumpkin seeds, walnuts, and almonds.

L-citrulline is often considered more effective at raising blood L-arginine levels, and thus nitric oxide, because it bypasses the liver and is converted to L-arginine in the kidneys. In contrast, much of the L-arginine consumed is broken down before it reaches the bloodstream.

Exercise increases blood flow and stress on the endothelial cells that line your blood vessels. This stimulates the enzyme nitric oxide synthase, leading to increased NO production and improved circulation.

Yes, some evidence suggests that certain mouthwashes kill the beneficial oral bacteria responsible for converting dietary nitrates into nitrite, a crucial step in one of the NO production pathways. Limiting its use may help preserve these bacteria.