Nitric oxide (NO) is a simple gaseous molecule that acts as a signaling molecule throughout the human body, playing a role in numerous physiological processes, including nerve signaling and immune response. The body’s natural production of NO is supported by consuming foods and drinks that contain its precursors. This article explores common beverages that can help boost the body’s nitric oxide production.
Nitric Oxide and Vascular Function
Nitric oxide’s primary function in the circulatory system is to regulate blood flow and maintain the health of the blood vessel lining, known as the endothelium. This molecule is continually produced by the endothelial cells, acting as a local messenger to the surrounding muscle tissue.
When nitric oxide is released, it signals the smooth muscles within the blood vessel walls to relax. This relaxation causes the blood vessel to widen, a process called vasodilation. Vasodilation improves blood circulation efficiency, which helps reduce strain on the heart.
Maintaining healthy levels of nitric oxide also provides anti-inflammatory and anti-clotting effects. It prevents blood components, such as platelets, from clumping together and adhering to the vessel walls. By promoting flexible, open arteries, nitric oxide supports the efficient transport of oxygen and nutrients throughout the body.
How Dietary Nitrates Become Nitric Oxide
The body has two main ways to produce nitric oxide, but the one influenced by diet is the Nitrate-Nitrite-NO pathway. This process requires a specific sequence of steps involving the body’s own bacteria.
After consumption, inorganic nitrate (NO3-) from food and drink is rapidly absorbed into the bloodstream. Up to a quarter of this circulating nitrate is actively taken up by the salivary glands, where its concentration increases significantly. This nitrate-rich saliva is then exposed to the oral microbiome.
Commensal bacteria, specifically those on the tongue’s surface, possess enzymes called nitrate reductases. These enzymes reduce nitrate to nitrite (NO2-), the next precursor in the pathway. When this nitrite-rich saliva is swallowed, the acidic environment of the stomach converts the nitrite into nitric oxide.
Key Beverage Sources of Nitric Oxide Precursors
The most effective beverages for increasing nitric oxide availability are those naturally rich in dietary nitrate or L-citrulline. These compounds serve as the raw materials for the body’s NO production pathways.
Beetroot Juice
Beetroot juice is recognized as a leading source due to its exceptionally high concentration of inorganic nitrate. Consuming a small amount of beet juice can lead to a measurable increase in circulating nitric oxide levels within an hour. The substantial nitrate content of beets forms the basis for most dietary nitrate supplementation research.
Green Leafy Vegetable Juices
Juices made from certain green leafy vegetables also provide a significant nitrate boost. Spinach, kale, and arugula are particularly high in these compounds, and juicing offers a concentrated dose. Regular consumption of these nitrate-rich vegetable juices helps maintain stable, elevated levels of nitric oxide precursors.
Watermelon and Polyphenol Juices
Watermelon juice works through a different mechanism, as it is a rich source of the amino acid L-citrulline. Once consumed, L-citrulline is recycled by the kidneys and converted into L-arginine, the substrate for the body’s main NO-producing enzyme. Pomegranate and grape juices are also noted for their high polyphenol content, which helps protect the nitric oxide molecule from breaking down too quickly.
Optimizing the Nitric Oxide Content of Drinks
Maximizing the benefit from nitric oxide-boosting drinks involves considering preparation methods and co-consumed substances. Since the conversion of nitrate to nitrite relies on specific oral bacteria, maintaining a healthy oral microbiome is important.
Antiseptic mouthwashes kill bacteria indiscriminately, eliminating the beneficial nitrate-reducing bacteria. This disruption significantly impairs the first step of the Nitrate-Nitrite-NO pathway, reducing systemic nitric oxide levels. Therefore, avoid using strong antibacterial mouthwash immediately after consuming nitrate-rich drinks.
Heat can also degrade beneficial compounds; thus, it is recommended to consume these beverages raw or with minimal processing to preserve the maximum concentration of dietary nitrates. For an acute boost in nitric oxide levels, drinks are often consumed 60 to 90 minutes before exercise, allowing time for the full conversion process to occur.