Nasal Nitric Oxide: Benefits and How to Increase It Naturally

Nasal breathing is often recommended for better breathing habits, but there's another important reason to breathe through your nose: nitric oxide.

Your nose and sinuses naturally produce this gas, which helps relax your airways and blood vessels and supports your body's natural defenses. When you breathe through your mouth, you largely bypass this built-in source.

Your body makes nitric oxide every day, but how you breathe affects how much of it you actually benefit from. So how does your nose make nitric oxide, what does it do, and how can you increase nitric oxide naturally through simple breathing habits? This blog explains it all in plain language.

What is Nitric Oxide?

Nitric oxide (NO) is a gas your body makes to send signals between cells. It isn't the same as nitrous oxide, the "laughing gas" used at the dentist.

Researchers discovered its role in the 1980s, work for which they were awarded the 1998 Nobel Prize in Physiology or Medicine. Nitric oxide is very short lived (it breaks down in seconds) so your body can't store it. It's made continuously in three main places:

• Your nose and sinuses: nitric oxide travels with the air you breathe in and acts mainly in your airways and lungs.
• Your blood vessels: their lining produces nitric oxide to help regulate blood flow.
• Your food: nitrate in vegetables can be converted into nitric oxide.

What stimulates nitric oxide production?

Your body uses two main pathways:

1. The enzyme pathway. Enzymes called nitric oxide synthases make nitric oxide from the amino acid L-arginine. This happens continuously in your sinuses, and in your blood vessels, it increases when blood flow speeds up, such as during exercise.
2. The nitrate pathway. Bacteria on your tongue convert nitrate from vegetables into nitrite, which your body then turns into nitric oxide.

Your breathing affects how much nasal nitric oxide reaches your lungs, while movement and food support the other pathways.

What Does Nitric Oxide do in The Body?

To understand what nitric oxide does in the body, think of it as a messenger. It gets to the very thin layer of muscle in the vessel wall and tells that muscle to relax. It only lasts a fraction of a second, but that's all it takes to set off a cascade of events inside the cell, like knocking over the first domino in a line.

Benefits of Nitric Oxide

1. Improves blood flow

Nitric oxide does increase blood flow (one of the most well established findings in physiology). Its primary effect on the blood vessels is to relax the smooth muscle in the walls of the vessels, leading to vasodilation and improved blood flow.

Most of it is nitric oxide produced in the vessel wall. If you're on blood pressure medication then you should discuss this with your doctor prior to making any changes you intend to make to it.

2. Supports your airways and breathing

When you inhale through your nose, small quantities of nitric oxide get into your lungs. There it may help to dilate your airways and relax the blood vessels around the alveoli, thus keeping airflow and blood flow in balance. That's one of the ways NO helps with breathing.

3. Helps defend against germs

Lab research has shown that nitric oxide can kill bacteria and inhibit the multiplication of some viruses. Lundberg and Weitzberg (in their research) would describe nasal nitric oxide as very much part of the airway's first line of defence and I see the nose in exactly the same way. A lot of this evidence is from lab studies so nose breathing is not a way of preventing or treating infection.

4. Supports nerve and immune signaling

Nitric oxide also helps nerve cells pass signals and helps immune cells respond to infection or injury.

The Connection Between Nitric Oxide and Nasal Breathing

How is nitric oxide produced in the nose?

Most nasal nitric oxide comes from your paranasal sinuses, the air-filled spaces around your nose. The cells lining them make it continuously, and it gradually mixes into the air flowing through your nose.

When you breathe in through your nose, that air carries nitric oxide into your lower airways and lungs. Research by Lundberg and Weitzberg, along with Djupesland and colleagues, helped establish the nose and sinuses as a major source of the nitric oxide we breathe.

Nose breathing vs mouth breathing: the nitric oxide difference

When you breathe through your mouth, air skips your nose and sinuses, so you largely miss out on their nitric oxide. I breathed through my mouth for years without realizing it, so I know how easy this habit is to miss.

Nitric oxide is only one reason your nose matters. Nasal breathing also:

• Filters, warms, and humidifies the air.
• Adds gentle resistance that tends to slow your breathing.
• Supports a calmer breathing pattern. Fast, upper-chest breathing signals danger to your brain, so breathe the opposite of stress: soft, slow, and gentle, through the nose.

That said, nose breathing suits rest, daily activity, and easier exercise. At very high intensity, it can limit how much air you move.

Breathing Techniques for Nitric Oxide

These simple techniques help you increase nitric oxide in your body naturally by making better use of what your nose already produces.

Breathe through your nose during the day.

Check in a few times a day, such as at your desk or on a walk. If your mouth is open, gently close it and breathe through your nose. Resting your tongue on the roof of your mouth helps open your airway so air flows more easily through your nose.

Keep nasal breathing going at night.

Waking up with a dry mouth can signal that you breathe through your mouth during sleep, which means missing out on nasal nitric oxide for hours. A gentle lip-supporting tape such as MyoTape encourages nasal breathing without sealing your mouth shut. If you snore loudly, wake up gasping, or can't breathe comfortably through your nose, speak with a doctor before using any mouth tape.

Does humming increase nitric oxide?

Yes, by a lot. In a 2002 study, Weitzberg and Lundberg found that nasal nitric oxide rose about 15-fold during humming compared with quiet breathing out. The vibration speeds up air exchange between your sinuses and nasal passages, flushing out more stored nitric oxide.

That makes humming the fastest way to increase nitric oxide in your nose. Keep in mind the boost is local to your nose, not your whole body.

How long to hum for nitric oxide

There's no proven ideal duration. Research shows a single hum produces an early burst of nasal nitric oxide that then declines, so several short hums work better than one long one. Here's the practice I recommend:

1. Sit comfortably with your mouth closed.
2. Breathe in gently through your nose.
3. Hum softly as you breathe out through your nose, for a count of three or four.
4. Repeat for a few comfortable rounds.

Breathe light and slow

I teach soft, quiet breathing as a first step for anyone new to nasal breathing. Breathe in and out through your nose, then gently slow down and soften each breath until you feel a light hunger for air, without strain.

The Oxygen Advantage Method

These techniques come from the Oxygen Advantage method, the functional breathing method I developed. It works across three dimensions of breathing:

• Biomechanical
• Biochemical
• Psychophysiological.

The method trains full-time nasal breathing at rest, during sleep, and during easier exercise, using exercises such as Breathe Light, Breathe Slow, Breathe Low, and nasal humming.

It doesn't force your body to make extra nitric oxide. It helps you build habits that let you use what your nose already produces.

Why does Nitric Oxide Increase with Exercise?

When you exercise, blood moves faster through your vessels and drags along their walls, a force called shear stress. Your vessel lining responds by releasing more nitric oxide, which widens the vessels so more blood reaches your muscles. Over time, regular activity, even brisk walking, is associated with healthier blood vessel function.

Nasal breathing suits easier sessions. At low to moderate intensities, it can reduce breathing rate and the amount of air you move while still meeting your body's needs.

At maximal effort, a small 2025 study of healthy adults (BreathWISE) found nasal-only breathing limited airflow and reduced peak performance, so open your mouth when you push hard.

How to Increase Nitric Oxide Naturally: A Simple Daily Approach

Breathing comes first, but food and everyday habits also shape how much nitric oxide you make. Here's how to get nitric oxide naturally from each angle.

Foods that increase nitric oxide

Nitrate-rich vegetables feed the nitrate pathway. Good choices include leafy greens such as arugula and spinach, beetroot, celery, and radishes. After you eat them, bacteria on your tongue convert their nitrate to nitrite, which your body turns into nitric oxide. If you take blood pressure medication, check with your doctor before making major dietary changes.

What depletes nitric oxide in your body?

Several factors may reduce how much nitric oxide you make or how long it stays active:

• Mouth breathing: air bypasses your nasal nitric oxide.
• Inactivity: less blood flow means less signal for release.
• Smoking: it increases oxidative stress, which breaks down nitric oxide.
• Aging: blood vessels tend to produce less as we get older.

Mouthwash and nitric oxide

Antiseptic mouthwash can kill the tongue bacteria that turn nitrate into nitrite. In a 2013 study by Kapil et al., a week of twice-daily chlorhexidine mouthwash cut oral nitrite production by 90% and blood nitrite by 25%, and slightly raised blood pressure. Don't stop a mouthwash your dentist prescribed, but if you use one daily without a dental reason, ask your dentist whether you need it.

What Dr. Nathan Bryan says about nitric oxide

Dr. Nathan Bryan has researched nitric oxide for more than 30 years and became a professor of molecular medicine at the University of Texas Medical School in Houston. He sat down with me on the Oxygen Advantage podcast to talk about how the body makes nitric oxide and what gets in its way.

In the video, Dr. Bryan explains:

• Nasal nitric oxide works in your lungs. He describes it as both an airway opener and a blood vessel relaxer, and says the body converts it into longer-lasting molecules that carry its effects for minutes to hours.
• Production tends to fall with age. The enzyme that makes nitric oxide, also found in the nasal lining, works less well as we age, so older adults may get less from nasal breathing.
• Humming frequency matters. Citing Karolinska Institute research, he says certain humming frequencies release more nitric oxide, depending on your sinus size.
• Moderate exercise is enough. A brisk walk triggers release. He breathes through his nose during his morning workout and switches to mouth breathing for high-intensity intervals.
• Mouth breathing works against you. It bypasses the nose, dries the mouth, and changes the bacteria on your tongue.
• Skip arginine supplements. Your cells already have plenty, so he points to dark leafy greens instead.

These are Dr. Bryan's views. He also recommends cutting back on sugar and getting regular sunlight. If you take medication or use a prescribed mouthwash, talk to your doctor or dentist before changing your routine.

Your daily nitric oxide checklist

• Breathe through your nose at rest and during easy activity.
• Rest your tongue on the roof of your mouth.
• Support nasal breathing at night, unless a doctor advises otherwise.
• Hum gently through your nose for a few rounds each day.
• Move daily, even if it's just a walk.
• Eat nitrate-rich vegetables.
• Check with your dentist about using antiseptic mouthwash daily.

Frequently Asked Questions

What is the fastest way to increase nitric oxide?

Humming through your nose produces the greatest rise in nasal nitric oxide (one study found a 15-fold increase). For nitric oxide in the blood vessels, exercise is by far the most reliable everyday trigger.

Does nose breathing increase nitric oxide?

Nose breathing delivers the nitric oxide from your sinuses into your lungs whereas mouth breathing largely sidesteps it. Your sinuses produce it either way, it's just that you get to benefit from it via nose breathing.

Does mouthwash lower nitric oxide?

Antiseptic mouthwash can reduce the tongue bacteria that help produce nitric oxide. A 2013 study found a week of chlorhexidine mouthwash cut blood nitrite by about 25%.

Is nasal breathing always the best during exercise?

It's good at rest and during low to moderate exercise, but at maximal effort it can actually restrict airflow and impair peak performance. You have to breathe through your mouth when you're really pushing.

Is nitric oxide the same as nitrous oxide?

No. Nitric oxide is a signaling gas your body makes. Nitrous oxide, or laughing gas, is a different gas used as a mild anesthetic.

Conclusion

Your nose is a built-in source of nitric oxide. Your sinuses produce it every day, and nose breathing carries it into your lungs, where it supports your airways and helps protect against germs.

How you breathe determines how much you use. Breathe through your nose day and night, hum for a few rounds, move regularly, and eat nitrate-rich vegetables. These simple habits support your body's own production.

To learn more, explore the Oxygen Advantage breathing method.

Sources

• Weitzberg E, Lundberg JO (2002). Humming greatly increases nasal nitric oxide. Am J Respir Crit Care Med. Source of the 15-fold figure.
• Maniscalco M et al. (2003). Assessment of nasal and sinus nitric oxide output using single-breath humming exhalations. Eur Respir J (PMID 12952268). Source of the early peak, then decline.
• Kapil V, Haydar SM, Pearl V, Lundberg JO, Weitzberg E, Ahluwalia A (2013). Physiological role for nitrate-reducing oral bacteria in blood pressure control. Free Radic Biol Med.
• Lundberg JO, Weitzberg E (1999). Nasal nitric oxide in man.
• Djupesland PG et al. (2001). Nitric oxide in the nasal airway.
• Mapelli M, Salvioni E, Mattavelli I, et al. (2025). Nasal vs. oral BREATHing WIn Strategies in healthy individuals during cardiorespiratory Exercise testing (BreathWISE). PLoS One 20(7):e0326661. doi:10.1371/journal.pone.0326661