Pranayama

Alternate nostril breathing

By GyroscopeUpdated November 15, 20269 sources

Family

Pranayama

Breaths

No set pace, 7.5 on our timer

Carbon dioxide

Depends on the practice

How well tested

Weak

Risk

Low

Timer

Run it on this page

Alternate nostril breathing means breathing in through one nostril and out through the other, closing each side in turn with your fingers. It’s slow, calm and takes a minute to learn. Small trials found blood pressure fell a few points, but they disagreed a lot about how much. We’d do it as a pleasant way to slow your breathing down, and we wouldn’t count on it for your blood pressure.

Yoga teachers describe it as a way to bring the body into balance. The classic texts say it cleans the nadis, the channels prana is said to flow through. Part of that rests on something real. At any moment one side of your nose is more open than the other, and the open side switches through the day and night. Your nose already alternates on its own, so doing it on purpose feels like it must be doing something deep.

The measured effects are more ordinary. People breathe more slowly when they do it, and slow breathing calms the heart whichever nostril the air goes through. No trial has pulled the switching apart from the slowing yet.

What it is and where it comes from

The Hatha Yoga Pradipika, a yoga manual written by Swami Swatmarama around the 15th century, lays it out. You breathe in through the left nostril, hold as long as you comfortably can, and breathe out through the right. Then you do the same starting on the right. The text says the nadis become clean after three months. Its schedule would scare most people off, with four sittings a day working up to 80 holds a sitting, or 320 a day.

Today it’s called nadi shodhana, which means channel cleaning, or anulom vilom, and many versions drop the long holds.

In 1895 a doctor named R. Kayser first described the nasal cycle. The lining on one side of your nose swells while the other shrinks, then they swap, and the total air you get stays about the same. In 2024, doctors in Ulm, Germany, had 30 healthy people wear a nasal airflow sensor for 48 hours. Every one of them had a nasal cycle, and each phase lasted about three and a half hours on average.

How to do it

1. Sit up on a chair or the floor.
2. Set your right hand. Fold your index and middle fingers into your palm. Your thumb closes your right nostril and your ring finger closes your left, the grip used in a 2014 trial in India. The Cleveland Clinic teaches thumb and index finger, and that works too.
3. In through the left. Close the right side with your thumb and breathe in for four.
4. Out through the right. Close the left side, lift your thumb, and breathe out for four.
5. In through the right, out through the left. Four in, switch fingers, four out. Those two breaths make one round.
6. Keep going for about five minutes a day, as the Cleveland Clinic’s article suggests.

A round takes 16 seconds, which is 7.5 breaths a minute, a little faster than six a minute in the shape below. The Cleveland Clinic’s article says it can feel energizing, and it suggests 4-7-8 for right before bed instead.

A simple way to picture it

Breathing through one nostril is like drinking through one straw instead of two. You still get all you want, it just comes more slowly, so each breath stretches out without you forcing it.

What happens in your body

Your heart speeds up a little on every breath in and slows on every breath out. The swing gets bigger as your breathing slows toward six a minute. Why does slow breathing calm your heart? has the long version.

In the 2014 trial in Haridwar, India, 26 young men practiced for 15 minutes while machines recorded them. Their breathing slowed, their heart rate variability rose and their top blood pressure number fell about 4.5 points (mmHg). When they spent the same time just paying attention to their breath, their pressure didn’t drop. A group who just sat still started breathing faster, which the researchers put down to boredom.

The nasal cycle is run by the hypothalamus, deep in the brain, so your nose switches sides without you deciding. Your fingers take over that job for a few minutes. Yoga teaches that the switching cleans the nadis, a claim about energy that these trials didn’t try to measure.

What the evidence shows

The 2024 review sounds strong. But the six trials disagreed so much about the size of the drop that the authors said to interpret it with care, and most weren’t double blinded. The 2017 review found that nobody has settled on a standard version, so trials used different counts, holds and session lengths.

We couldn’t find a trial that compared it with breathing through both nostrils at the same slow pace. Until someone runs one, nobody knows whether switching sides adds anything.

Who should skip it

Almost nobody needs to, since it’s slow and nothing in it is forced.

• Blocked nose. Breathe through both sides and keep the count.
• Lightheaded. Breathe smaller. Breathing more air than you need, even slowly, lowers the carbon dioxide in your blood, and MedlinePlus lists lightheadedness as the result. Why do I feel dizzy after breathing exercises?
• High blood pressure. Keep taking what you’ve been prescribed. To see what it does for you, measure at home before you start and after a few weeks.
• Short of breath at rest. Ask your doctor about it. MedlinePlus lists it as a reason to see your provider.