Why Cortisol Matters
Cortisol gets a bad reputation, but it is not your enemy. It is the hormone that wakes you up in the morning, helps you run for the bus, and keeps you alert when you need to focus. The problem starts when it refuses to switch off. High cortisol over time leaves you feeling tired but wired, affects your sleep, stores fat around your middle, and generally makes life feel harder than it needs to be.
Luckily, you do not need fancy equipment, a gym membership, or a week at a spa to start bringing cortisol back to balance. Your breath is literally right under your nose, and it is one of the fastest ways to tell your nervous system that you are safe. Let us look at three of the most studied breathing techniques, what the research says, and then finish with one simple practice you can use every day.
Diaphragmatic Breathing – The Belly Breath
What it is
This is the one your yoga teacher always talks about. Instead of breathing into the top of your chest, you breathe deep into the belly so it rises and falls with each breath. Place a hand on your belly, breathe in through your nose until your hand lifts, then breathe out slowly and feel it sink again.
Why it works
This type of breathing stimulates the vagus nerve, which is like pressing the brake pedal on your stress response. It slows your heart rate, lowers blood pressure, and tells your brain there is no tiger chasing you.
What research says
Studies are promising. A review found that regular belly breathing lowers breathing rate, calms the nervous system and, in some cases, brings cortisol levels down. In one eight-week study, participants who practiced daily had noticeably lower salivary cortisol compared with people who did nothing. Translation: belly breathing is simple, free, and actually does what it says on the tin.
Box Breathing – Calm Under Pressure
What it is
Box breathing is exactly what it sounds like – four equal sides. Breathe in for four counts, hold for four, breathe out for four, hold again for four. Picture a square in your mind and trace each side as you breathe.
Why it works
The holds between breaths are surprisingly powerful. They give your body time to adjust, slowing everything down and creating a sense of control. This technique is so reliable that Navy SEALs use it to stay cool under fire.
What research says
Direct cortisol studies are thinner on the ground, but research shows box breathing slows the heart, lowers blood pressure, and steadies the mind. In one recent trial, people using structured breathwork techniques – including box breathing – calmed down faster than those who just meditated. So if you need to stop a stress spiral before a big meeting or when your inbox explodes, this one is your friend.
Coherent Breathing – Finding Your Rhythm
What it is
Coherent breathing is slower and more meditative. Aim for about five or six breaths per minute – one breath every ten seconds. This pace lines up your breathing with your heart rhythm, which is great for heart rate variability and general calm.
Why it works
This technique fine-tunes the communication between heart and brain, giving your system a signal to shift into rest and digest mode.
What research says
The evidence shows that any slower, mindful breathing can make a difference. A meta-analysis found breathwork reliably lowers stress and anxiety. A large study comparing coherent breathing with a faster version found both groups felt calmer. The take-home? You do not have to be perfect – just slow down, breathe steadily and your body will thank you.
Comparing the Three
Diaphragmatic breathing is the easiest starting point and takes almost no learning curve. Box breathing is brilliant for those moments when you feel tense and need a quick reset. Coherent breathing is perfect for longer, meditative sessions where you want to really sink into calm. The best technique is the one you will actually do.
One Easy Daily Practice
Try this simple five-minute reset:
Sit comfortably and place one hand on your belly.
Breathe in through your nose for a count of four, feel your belly rise.
Exhale for a count of six, feel it fall.
Repeat for five minutes.
The longer exhale is the secret ingredient. It tells your nervous system the danger has passed and lets cortisol settle back down.
Make Breathing a Habit
Your breath is always with you, which means you have a built-in stress reset wherever you are. These techniques do not just make you feel calmer, they have been shown to lower physical stress markers like heart rate, blood pressure and, yes, cortisol. Five minutes a day is a small investment with a big payoff for your mind and body.
✨ Press Pause and Breathe ✨
Take a moment for yourself. My Press Pause video is a free 10-minute guided practice to help you reset, breathe deeply, and feel calmer.
References
Anwer, S., et al. (2023) Effect of exercise combined with mindfulness breathing on cortisol levels in women with type 2 diabetes, Frontiers in Physiology, 14, 1186546.
https://www.frontiersin.org/articles/10.3389/fphys.2023.1186546/full
Balban, M. Y., et al. (2023) Breathwork vs meditation for acute stress regulation: a randomized controlled trial, Cell Reports Medicine, 4(2), 100983.
https://doi.org/10.1016/j.xcrm.2023.100983
Hagemann, H., et al. (2023) Slow-paced breathing for stress reduction: a randomized controlled trial, Scientific Reports, 13, 10219.
https://doi.org/10.1038/s41598-023-37267-8
Jerath, R., et al. (2006) Physiology of long pranayamic breathing, Medical Hypotheses, 67(3), pp. 566–571.
https://doi.org/10.1016/j.mehy.2006.02.042
Lehrer, P. M., and Gevirtz, R. (2014) Heart rate variability biofeedback: how and why does it work?, Frontiers in Psychology, 5, 756.
https://doi.org/10.3389/fpsyg.2014.00756
Ma, X., et al. (2017) The effect of diaphragmatic breathing on attention, negative affect and stress in healthy adults, Frontiers in Psychology, 8, 874.
https://doi.org/10.3389/fpsyg.2017.00874
Sapolsky, R. M. (2004) Why Zebras Don’t Get Ulcers. 3rd edn. New York: Holt Paperbacks.
https://www.penguinrandomhouse.com/books/168214/why-zebras-dont-get-ulcers-by-robert-m-sapolsky/
Saoji, A. A., et al. (2019) Effects of yogic breathing techniques on stress, anxiety, and cardiovascular autonomic variables, Indian Journal of Physiology and Pharmacology, 63(3), pp. 232–239.
https://www.ijpp.com/IJPP%20archives/2019_63_3/232-239.pdf
Seppälä, E. M., et al. (2022) Breathwork interventions for mental health: systematic review and meta-analysis, Scientific Reports, 12, 22933.
https://doi.org/10.1038/s41598-022-27247-y
Zaccaro, A., et al. (2018) How breath-control can change your life: a systematic review, Frontiers in Human Neuroscience, 12, 353.
https://doi.org/10.3389/fnhum.2018.00353
