If you searched for “nitrous oxide,” you’re most likely looking for nitric oxide, a molecule your body produces naturally to relax blood vessels, improve circulation, and support cardiovascular health. (Nitrous oxide is laughing gas, used in dentistry and racing engines.) The good news: you can meaningfully increase your nitric oxide levels through food, exercise, sunlight, and a few simple habits. Here’s how.
Eat Nitrate-Rich Vegetables
The most direct dietary route to higher nitric oxide is eating vegetables high in nitrates. Your body converts these nitrates into nitrite, then into nitric oxide. The top sources are beets, arugula, spinach, kale, and cabbage. A nitrate-rich meal containing leafy greens or beet juice has been shown to significantly lower both systolic and diastolic blood pressure, a direct marker of nitric oxide doing its job.
Beetroot juice concentrate is the most studied form. The Australian Institute of Sport recommends 350 to 500 mg of nitrate (roughly one concentrated shot of beetroot juice) consumed two to three hours before exercise for measurable performance benefits. Research also shows that going above about 600 to 750 mg in a single dose doesn’t produce additional benefit, so more isn’t necessarily better.
Don’t Kill Your Oral Bacteria
This one surprises most people. The nitrate-to-nitric-oxide conversion starts in your mouth, where specific bacteria on your tongue reduce nitrate into nitrite. Antiseptic mouthwash wipes out these bacteria. In one study, using chlorhexidine mouthwash abolished the blood pressure drop that normally follows nitrate supplementation. The protective effects on the stomach lining also disappeared. If you’re eating beets and greens specifically to boost nitric oxide, frequent use of antiseptic mouthwash may be undoing much of the benefit.
Choose Citrulline Over Arginine
Your body also makes nitric oxide from amino acids, and the two supplements you’ll see marketed for this are L-arginine and L-citrulline. Both feed into the same pathway, but citrulline is the better choice. It increases the body’s own arginine production more efficiently than taking arginine directly, because citrulline gets recycled through a dedicated enzyme complex that channels it straight into nitric oxide synthesis. Arginine, by contrast, gets partially broken down in the gut and liver before it ever reaches that pathway. Citrulline is found naturally in watermelon, though supplemental doses are far higher than what you’d get from food.
Exercise for Blood Flow
When you exercise, blood moves faster through your arteries, creating a physical force called shear stress against the vessel walls. This mechanical signal activates the enzyme in your blood vessel lining that produces nitric oxide. In a controlled study, rhythmic forearm exercise over two hours increased the activation of this enzyme by 57% in the cells lining the artery, even though the total amount of the enzyme didn’t change. The body didn’t make more of the machinery; it simply turned on what was already there.
Any exercise that gets your heart rate up and blood flowing will trigger this effect. Running, cycling, swimming, and resistance training all qualify. The key factor is sustained increases in blood flow through your vessels, which is why sitting all day is so detrimental to vascular health and why even moderate daily movement makes a real difference.
Get Some Sunlight
Your skin stores nitric oxide in a form that sunlight can release. When UVA rays hit your skin, they trigger a dose-dependent release of nitric oxide from stores concentrated in the upper layer of the skin. This process doesn’t rely on the same enzyme pathway that exercise uses. It’s a completely independent mechanism. In a study of 24 healthy volunteers, UVA exposure lowered blood pressure while shifting circulating nitrogen compounds in a pattern consistent with nitric oxide release. This may partly explain why cardiovascular disease rates tend to be higher at northern latitudes and during winter months.
Breathe Through Your Nose
Your paranasal sinuses, the air-filled cavities around your nose, continuously produce nitric oxide at concentrations far higher than what’s found in your lower airways. When you breathe through your nose, you carry this sinus-produced nitric oxide down into your lungs, where it helps open up blood vessels and improves oxygen uptake. Mouth breathing bypasses this reservoir entirely. The ethmoid sinuses (between your eyes) and the process of passive diffusion appear to contribute most of this output, based on computational modeling of actual patient anatomy.
Protect the Nitric Oxide You Already Make
Nitric oxide is extremely short-lived in the body. Free radicals, particularly a type called superoxide, destroy it almost on contact. This is where antioxidants come in. Vitamin C, vitamin E, and foods rich in polyphenols (like dark berries, dark chocolate, and green tea) help neutralize these free radicals before they can break down your nitric oxide. You don’t need megadoses. A diet that consistently includes colorful fruits and vegetables provides enough antioxidant support to meaningfully extend the working life of the nitric oxide your body produces.
What Works Against You
Several common habits quietly suppress nitric oxide production. Smoking damages the blood vessel lining where nitric oxide is made. A sedentary lifestyle means chronically low shear stress and minimal enzyme activation. High-sugar, highly processed diets promote the kind of oxidative stress that destroys nitric oxide before it can act. And as noted above, antiseptic mouthwash disrupts the oral bacteria essential to the nitrate pathway. Addressing even one or two of these can have a noticeable effect on vascular function over weeks to months.
If you’re taking blood pressure medication or nitrate-based heart drugs, increasing nitric oxide through aggressive supplementation could cause your blood pressure to drop too low. Food-based approaches like beets and leafy greens are generally safe, but concentrated supplements deserve a conversation with whoever manages your prescriptions.