2023Cell Reports Medicine
Balban et al.
111 adults, 1 month
Five minutes a day of cyclic sighing (two inhales, one long exhale) improved mood and lowered breathing rate more than mindfulness meditation.
Find on PubMed ↗Research library · Mind & mood
Stress and your nervous system
Short bursts of stress make you sharper. Stress that never switches off raises blood pressure, inflammation and heart risk. Your breath is the fastest remote control you have over your nervous system.
Good evidence5 mina day of slow 'cyclic sighing' lifted mood more than mindfulness meditationBalban 2023, Cell Rep Med, 111 adults
1.6×heart attack and stroke risk per step up in stress-centre (amygdala) activity on brain scansTawakol 2017, Lancet, 293 adults
8 wkof mindfulness training worked as well as a common anxiety medicineHoge 2023, JAMA Psychiatry, 276 adults
01
The basics
Two pedals: accelerator and brake
Your autonomic nervous system runs in the background. The sympathetic side is the accelerator: fight or flight, faster heart, tense muscles, sugar released into the blood. The parasympathetic side, led by the vagus nerve, is the brake: rest, digest and repair.
When your brain senses a threat, a chain called the HPA axis releases cortisol. That's useful for a deadline or a sprint. The problem is when it never settles: months of high stress are linked to high blood pressure, belly fat, poor sleep, lower immunity and heart disease.
Breathing is the one part of this system you can steer directly. Breathing in speeds the heart slightly; a long, slow exhale slows it by activating the vagus nerve. That's why slow breathing calms you within minutes.
Cyclic sighing: the calming breath
Two inhales through the nose, then a long, slow exhale through the mouth. Heart rate rises a little on the way in and falls on the long way out.
02
How it works
How a stress response works
1
Threat spotted
The amygdala, your brain's alarm, reacts to danger, worry or pressure.
2
Alarm sounds
Adrenaline and cortisol are released within seconds to minutes.
3
Body revs up
Heart rate, blood pressure and blood sugar rise; digestion pauses.
4
Exhale switches it off
Slow breathing, movement and safety signals turn on the brake.
03
Measure it
How stressed are you?
- Perceived Stress Scale (PSS-10): 10 questions about the last month. It's free online and widely used in research.
- HRV and resting heart rate: a falling HRV and rising morning pulse over several days often reflect stress, not just training.
- Body signs: clenched jaw, shallow breathing, poor sleep, gut upset, snapping at people.
- When to get help: if stress stops you sleeping, working or enjoying things for more than two weeks, talk to a doctor.
Try your number
LowModerateHigh
040
Perceived Stress Scale (Cohen 1983). Scores are a guide, not a diagnosis.
04
What the research says
The key studies
2017Lancet
Tawakol et al.
293 adults, brain scans
Higher resting activity in the amygdala predicted heart attacks and strokes over about 4 years, partly through bone-marrow activity and artery inflammation.
Find on PubMed ↗2023JAMA Psychiatry
Hoge et al.
276 adults with anxiety
An 8-week mindfulness course reduced anxiety as much as the medicine escitalopram.
Find on PubMed ↗2023Scientific Reports
Fincham et al.
12 trials, 785 adults
Breathwork lowered self-reported stress, anxiety and depression compared with control groups.
Find on PubMed ↗2015Lancet
Kivimäki et al.
528,908 adults (stroke analysis)
Working 55+ hours a week was linked to a 33% higher risk of stroke compared with a standard week.
Find on PubMed ↗05
Take action
Daily ways to hit the brake
Small, repeatable habits work better than an occasional spa day.
- 1
Two sighs, long exhale
Breathe in through the nose, top up with a second short inhale, then exhale slowly through the mouth. Repeat for 5 minutes.
- 2
Move it out
A brisk 10–20 minute walk uses up stress hormones and lifts mood.
- 3
Get outside
Morning daylight and green space lower stress and help sleep.
- 4
Talk it through
Sharing a worry with someone you trust lowers the stress response.
- 5
Set a stop time
Fix a time each evening when work messages go off.
- 6
Wind down
A 30-minute screen-free routine before bed protects sleep, the base of stress resilience.
06
Myth or fact
Common myths, checked
✕ MythAll stress is bad.
✓ FactShort, manageable stress (exercise, a challenge) makes you stronger. The harm comes from stress that never lets up.
✕ MythVenting anger by hitting a pillow helps.
✓ FactStudies show it tends to increase anger and aggression. Slow breathing or moving works better.
✕ MythYou need an hour of meditation.
✓ FactFive minutes of slow breathing a day changed mood in a month-long trial.
✕ MythStress is all in your head.
✓ FactIt changes heart rate, blood pressure, blood sugar, immunity and digestion.
07
Questions
Frequently asked
What is the vagus nerve?
A long nerve from the brainstem to the heart, lungs and gut. It's the main 'brake' of your nervous system.
Box breathing or cyclic sighing?
Both help. In the 2023 trial, cyclic sighing, with its longer exhale, had the biggest effect on mood.
Does caffeine make stress worse?
It can raise heart rate and anxiety in sensitive people. Keep it before noon if you're stressed or sleeping badly.
08
Sources
References and related topics
- Balban et al. (2023). Cell Reports Medicine. 111 adults, 1 month. PubMed ↗
- Tawakol et al. (2017). Lancet. 293 adults, brain scans. PubMed ↗
- Hoge et al. (2023). JAMA Psychiatry. 276 adults with anxiety. PubMed ↗
- Fincham et al. (2023). Scientific Reports. 12 trials, 785 adults. PubMed ↗
- Kivimäki et al. (2015). Lancet. 528,908 adults (stroke analysis). PubMed ↗