Diaphragmatic Breathing: What It Is, Who Studies It and What Research Shows
Diaphragmatic (belly) breathing explained in plain language: a gentle description from health sources, who studies it, what reviews found for stress, reflux and other uses, and when to stop.
Content last updated . This page has not been medically reviewed.
What it is
Diaphragmatic breathing is often called belly breathing or abdominal breathing. NCCIH describes breathing exercises that focus on taking slow, deep breaths, also called diaphragmatic breathing, as one family of relaxation techniques. [2] The idea is to let the breath move down toward the belly instead of lifting the shoulders and upper chest. For a plain-language explanation of the muscle itself, see how breathing works. To compare it with chest and pursed-lip breathing, see the side-by-side comparison.A gentle description from the sources
The NHS describes a stress-relief version: sit with back support, stand, or lie down; loosen tight clothing; and let the breath flow as deep down into the belly as is comfortable, without forcing it. It suggests breathing in through the nose and out through the mouth, and repeating for at least 5 minutes. [3] A hospital patient handout for people with COPD adds a hand-on-belly check: one hand on the stomach and one on the chest, feeling the stomach move out as you breathe in through the nose. [4]Comfort is the rule. If you feel lightheaded, tingly or short of breath, you may be breathing too fast or too deeply. MedlinePlus lists lightheadedness, dizziness, and numbness or tingling among the symptoms of overbreathing. [1] Stop, return to normal breathing and rest. Practice that brings more anxiety, intrusive thoughts or fear of losing control is also a reason to stop. [2]
What research shows
Most studies are small, use different breathing rates and session lengths, and cannot hide from participants which practice they are doing. Expectation may play a part.| Question | What the source found | Strength of evidence |
|---|---|---|
| Stress in adults | A systematic review found only three studies (one randomized trial, two quasi-experimental). All three reported lower stress, but results could not be pooled [5] | Promising but limited |
| Attention, mood and cortisol in healthy adults | In a trial of 40 people, an 8-week program of 20 sessions with a real-time feedback device and a very slow breathing rate lowered negative affect and cortisol compared with no treatment [6] | Promising but limited; the training was far more intensive than casual practice |
| Broad health effects | A 2026 review of 48 randomized trials found consistent benefits for reflux, anxiety and some other conditions, but only 2.12% of outcomes had low risk of bias [7] | Promising but limited |
| Reflux (GERD) | A 2026 meta-analysis of 10 trials (476 patients) found a modest improvement in symptom scores, with very high variation between studies; quality of life did not improve significantly [8] | Mixed |
| COPD | The 48-trial review found evidence inconsistent for COPD [7]; see pursed-lip breathing | Mixed |
| After heart surgery | The same review found diaphragmatic breathing less effective than standard care after cardiac surgery [7] | Evidence of less benefit than usual care |
| Stroke recovery | A meta-analysis of 6 studies (151 people) found better lung function measures only; the authors call the evidence limited [9] | Insufficient evidence |
NCCIH also reports preliminary evidence from a 2019 review of three studies that diaphragmatic breathing may help reduce stress. [2] That is the same small evidence base described above, not a separate body of trials.
Protocols in the 48-trial review ranged from 2 to 10 breaths a minute and from 3 to 45 minutes per session. [7] So "diaphragmatic breathing" in a study may not match what you would do at home. We did not find a trial showing that any one rate or session length is best: Proper evidence not found (we looked at the reviews above).
Teachers and training
Belly breathing is simple enough to learn from a health-service page, and it is often taught by clinicians in rehabilitation. We did not find a regulator or professional-body page that sets a standard for teaching it, so proper evidence not found for any required qualification. We do not list teachers. If you want a teacher, ask about their training, whether they work within a licensed health profession where you live, and what they do if you feel dizzy or anxious.Related reading
Gentle breathing and relaxation practices places this technique among others. Goal-level guidance is in breathing exercises for stress. Safety details are in breathwork safety.Frequently asked questions
Is belly breathing the same as deep breathing?
They overlap. NCCIH describes slow, deep breaths as diaphragmatic breathing. [2] The NHS says to let the breath go as deep as is comfortable, without forcing it. [3]
How long should I practice?
The NHS suggests at least 5 minutes, done regularly. [3] No trial we read shows that one length is best. [7]
Does diaphragmatic breathing lower stress?
Small studies suggest it may, but a systematic review found only three. [5]
Can it help acid reflux?
A 2026 meta-analysis found a modest improvement in symptom scores but warned the result needs cautious reading because studies differed so much. [8]
What should I do if I feel dizzy?
Stop and breathe normally. Dizziness and tingling are symptoms of overbreathing. [1]
More details: evidence, limits and cautions
The details behind this page: cautions, limits of the evidence and where sources disagree. Open any note to read it.
Safety first
Safety and side effects
Who should check with a clinician first: people with the conditions NCCIH names, and anyone with lung disease, heart disease or pregnancy. We did not find a source that lists who must avoid belly breathing, so this last part is general caution, not a rule from a source. Never change or stop prescribed medicines because of a breathing practice.
References
- MedlinePlus Medical Encyclopedia, Hyperventilation. U.S. National Library of Medicine. Read 2026-10-22.
- NCCIH, Relaxation Techniques: What You Need To Know. U.S. National Institutes of Health. Read 2026-10-22.
- NHS, Breathing exercises for stress. Page last reviewed 12 June 2026. Read 2026-10-22.
- UW Health, Breathing Techniques for COPD (patient and family handout). Read 2026-10-22.
- Effectiveness of diaphragmatic breathing for reducing physiological and psychological stress in adults: a quantitative systematic review. JBI Database System Rev Implement Rep 2019/2020. PubMed 31436595. Read 2026-10-22.
- The effect of diaphragmatic breathing on attention, negative affect and stress in healthy adults. Front Psychol. PubMed 28626434. Read 2026-10-22.
- The health effects of diaphragmatic breathing: a systematic review. Complement Ther Med 2026. PubMed 41482169. Read 2026-10-22.
- Efficacy and safety of diaphragmatic breathing exercises for gastroesophageal reflux disease: a systematic review and meta-analysis. J Clin Med 2026. PubMed 42123139. Read 2026-10-22.
- Efficacy of diaphragmatic breathing exercise on respiratory, cognitive, and motor function outcomes in patients with stroke: a systematic review and meta-analysis. Front Neurol 2024. PubMed 38283673. Read 2026-10-22.