Nitric oxide (NO) is a short-lived signaling molecule your body makes naturally. It helps regulate blood vessel function by signaling the muscles around your blood vessels to relax and widen, allowing blood to flow more easily.
Your body can produce nitric oxide from L-arginine, an amino acid, as well as through a pathway involving dietary nitrate from foods such as leafy greens and beetroot.
Beyond circulation, nitric oxide is also involved in exercise performance, platelet activity, and communication between cells. So, what are the benefits of nitric oxide, and how can you naturally support its production?
Benefits of Nitric Oxide
Nitric oxide plays several important roles throughout the body. Here are some of the key ways it supports your health.
1. Supports Healthy Blood Vessel and Cardiovascular Function
Nitric oxide is one of the key molecules that helps keep your blood vessels working properly. It signals the muscles surrounding them to relax, allowing the vessels to widen and blood to flow more easily.
This process, called vasodilation, helps regulate blood flow and contributes to healthy blood pressure. Nitric oxide also supports the endothelium, the thin layer of cells lining your blood vessels, which helps maintain normal vascular function.
This matters for cardiovascular health, too. When nitric oxide availability is reduced, blood vessels may not relax as effectively, contributing to endothelial dysfunction.
Reduced nitric oxide bioavailability has been associated with vascular problems such as hypertension, high cholesterol, diabetes, and heart failure.
A 2018 review suggested that dietary nitrate may support blood pressure, blood vessel function, arterial stiffness, platelet activity, and blood flow. However, the benefits were clearer in healthy people, while evidence in people at cardiovascular risk and on long-term cardiovascular outcomes remains limited.
2. May Support Exercise Performance
Exercise does more than work your muscles. It also affects nitric oxide, which helps your blood vessels respond to the increased demand for blood flow during physical activity.
Regular exercise has been linked to higher levels of nitric oxide and related metabolites, with both aerobic and high-intensity interval training showing benefits.
Dietary nitrate has also attracted attention for its potential effects on exercise performance. Your body can convert nitrate into nitrite and then nitric oxide, which may help muscles use oxygen more efficiently during exercise.
An umbrella review found that dietary nitrate may improve certain aspects of exercise performance, including endurance, distance covered, muscular endurance, and peak power. However, the results were mixed, and the quality of the underlying research was often low, so these benefits shouldn’t be overstated.
3. Helps Regulate Platelet Activity
Your blood needs to clot when you’re injured, but excessive platelet activation can cause problems. Nitric oxide helps keep this process in check by limiting platelet activation and their tendency to stick together.
Nitric oxide can regulate platelet activity through the NO-cGMP signaling pathway, helping maintain a balance between normal blood clotting and healthy blood flow.
This balancing effect helps support normal blood flow while preventing platelets from becoming unnecessarily active.
4. Plays a Role in Brain and Nerve Signaling
Nitric oxide isn’t limited to your blood vessels. Your brain uses it as a signaling molecule, helping nerve cells communicate, influencing neurotransmitter release, and supporting changes in connections between brain cells.
Because of these effects, nitric oxide has been studied for its possible role in memory and other aspects of brain function. But there’s an important distinction: having an important role in the brain doesn’t necessarily mean that increasing nitric oxide will make you think better.
In fact, a meta-analysis found no significant improvement in overall cognitive function or cerebral blood flow with nitrate or nitrite supplementation.
So, nitric oxide clearly matters for how the nervous system works, but whether increasing it can actually improve memory or brain performance is still an open question.
5. May Support Sexual Function
Nitric oxide has another important job that may surprise you: it helps your body produce an erection.
During sexual stimulation, nitric oxide is released in penile tissue, where it activates a signaling pathway that relaxes the smooth muscle and increases blood flow needed for an erection.
A review of 10 studies involving 540 men found that L-arginine supplements significantly improved erectile function and satisfaction in men with mild to moderate erectile dysfunction. Benefits were seen at doses of 1,500–5,000 mg, with mostly mild side effects.
L-arginine is an amino acid that your body uses to produce nitric oxide.
Erectile dysfunction (ED) is also associated with cardiovascular disease and endothelial dysfunction. A meta-analysis showed that men with ED had significantly poorer endothelial function than men without ED.
So, nitric oxide is an important part of normal erectile function, but it isn’t the whole story. Hormones, nerves, medications, diabetes, blood pressure, and overall cardiovascular health can all influence sexual function.
How Can You Support Healthy Nitric Oxide Production Naturally?
You do not need an elaborate supplement routine. Instead, focus on habits that support overall vascular health:
Eat more vegetables. Include nitrate-rich vegetables such as leafy greens and beetroot regularly.
Exercise regularly. Physical activity supports endothelial function and nitric oxide availability.
Do not smoke. Smoking can impair vascular function and nitric oxide availability.
Manage blood pressure. High blood pressure can damage the endothelium over time.
Eat a balanced diet. A diet rich in vegetables, fruits, legumes, whole grains, nuts, and seeds supports cardiovascular health more broadly.
Get enough sleep. Good sleep is part of maintaining healthy cardiovascular function.
Are There Any Side Effects of Nitric Oxide Supplements?
Nitric oxide itself isn’t usually what you buy in a supplement. Products marketed for boosting nitric oxide often contain ingredients such as L-arginine, L-citrulline, or nitrate, and the possible side effects depend on what’s actually in the product.
L-arginine, for example, may cause digestive problems such as nausea or diarrhea. It can also lower blood pressure, especially at higher doses, because nitric oxide relaxes blood vessels. This may be important if you’re already taking medication to lower your blood pressure.
More isn’t necessarily better, either. Some studies suggest that the benefits of L-arginine may not continue with long-term use. One clinical trial even raised safety concerns when high-dose L-arginine was given to people after a heart attack.
For these reasons, long-term or high-dose use of L-arginine and L-citrulline deserves some caution, particularly if you have an existing health condition or take medication. It’s worth speaking with a healthcare professional before starting a concentrated nitric oxide–boosting supplement.
The Bottom Line
Nitric oxide may be tiny, but its role in your body is significant. It helps regulate blood flow, support healthy blood vessels, influence platelet activity, and contribute to normal nerve signaling.
You don’t need to chase higher nitric oxide levels. Focus instead on regular physical activity, a balanced diet, and nitrate-rich vegetables such as leafy greens and beetroot to support healthy vascular function.
If you have an underlying health condition or take medications, talk with your healthcare professional before considering nitric oxide supplements or making significant changes to your diet.