If things have slowed down, your fruit bowl might be a better place to start than you think. Some specific foods and drinks have evidence for helping adults with chronic constipation. The British Dietetic Association's 2025 guidelines include kiwifruit, prunes, rye bread, high mineral water and psyllium, although the strength of evidence varies.
Natural laxatives are foods and drinks that may help soften stools and keep you regular. The British Dietetic Association's 2025 guidelines, based on 75 trials, include kiwifruit, prunes, rye bread, high mineral water and psyllium for chronic constipation, although much of the evidence is low certainty. Results can take a few weeks, and persistent changes are worth discussing with your GP.
What counts as a natural laxative?
A natural laxative is any food or drink that helps things move, usually by adding bulk, holding water in your stool or drawing water into the bowel. Some fruits also contain sorbitol, a natural sugar alcohol that may have a mild laxative effect. Standard advice has long been to eat more fibre.
In 2025, researchers published the first comprehensive, evidence based dietary guidelines for chronic constipation in adults, endorsed by the British Dietetic Association [1]. They reviewed 75 randomised trials and produced 59 recommendations, many based on low or very low certainty evidence [1]. They made no recommendation for whole diet approaches, such as a generally high fibre diet, because there was not enough trial evidence to make a specific recommendation [1]. That does not mean fibre rich foods or a balanced diet are unimportant.
Which foods may help you poo?
| Food or drink | Amount in the guidelines | How it may help |
|---|---|---|
| Green kiwifruit | 2 to 3 a day, for at least 4 weeks [1] | Fibre and water, may soften stools [2] |
| Prunes | 8 to 10 a day [1] | Fibre and sorbitol, may increase stool weight [3] |
| Rye bread | 6 to 8 slices a day, for at least 3 weeks [1] | Bulk and fibre, though this amount may not suit everyone |
| High mineral water | 0.5 to 1.5 litres a day [1] | Waters high in minerals such as magnesium may help; ordinary water differs |
| Psyllium | As a supplement, following the pack [1] | Forms a gel that softens stools |
Kiwifruit. In an international trial, people with constipation who ate two green kiwifruit a day had more complete bowel movements than at the start of the study [2].
Prunes and rye. In a UK trial, adults who usually ate little fibre and added prunes to their diet for four weeks had heavier stools and went more often than a control group [3]. The rye bread amount in the guidelines may not be realistic for everyone, and rye can increase wind or other gut symptoms in some people [1].
Whichever you try, it helps to notice how your routine responds. Gutsi, a gut health tracker, tracks frequency and consistency passively, which can help you see whether your regularity shifts over time.
Psyllium. Psyllium works best with plenty of fluid, as our guide to hydration and digestion explains.
How quickly do natural laxatives work?
The studies behind these dietary approaches generally assessed changes over several weeks [1]. Try one change at a time, follow any relevant guidance, and seek advice if constipation persists or worsens.
Your gut is often most active after breakfast thanks to the gastrocolic reflex, so leaving time for the toilet in the morning can help. Sitting with your knees raised above your hips, explained in our guide to the best position to poo, may make things easier. Stress can slow things down, and so can life stage: our piece on constipation in midlife covers why.
When should you see a GP about constipation?
Occasional constipation is common. What counts as normal varies, as our guide to how often you should poo explains, so the most useful question is whether something has changed for you.
See a GP if:
- your constipation is not improving with treatment [4]
- you are often constipated, bloated or have tummy pain [4]
- you have blood in your poo or have lost weight without trying [4]
- you feel tired all the time, or you are taking medicine that may be causing it [4]
Can you eat natural laxatives every day?
These are everyday foods, and the trials used them daily for several weeks; more wind is the most common side effect. Supplements are different. Psyllium should be taken following the label with plenty of fluid, and magnesium supplements are not suitable for everyone, so ask a pharmacist or GP before using one for constipation, especially if you have a health condition or take regular medicines.
Pick one food from the table, such as two kiwifruit with breakfast, and note how often you go and what it looks like over the next few weeks. If constipation persists or worsens, or comes with blood in your poo, unexplained weight loss or significant pain, speak to your GP [4].
References
- Dimidi, E., van der Schoot, A., Barrett, K., et al. (2025). British Dietetic Association guidelines for the dietary management of chronic constipation in adults. Journal of Human Nutrition and Dietetics, 38(5), e70133. https://pubmed.ncbi.nlm.nih.gov/41081513/
- Gearry, R., Fukudo, S., Barbara, G., et al. (2023). Consumption of 2 green kiwifruits daily improves constipation and abdominal comfort: results of an international multicenter randomized controlled trial. American Journal of Gastroenterology, 118(6), 1058-1068. https://doi.org/10.14309/ajg.0000000000002124
- Lever, E., Scott, S. M., Louis, P., Emery, P. W., & Whelan, K. (2019). The effect of prunes on stool output, gut transit time and gastrointestinal microbiota: a randomised controlled trial. Clinical Nutrition, 38(1), 165-173. https://doi.org/10.1016/j.clnu.2018.01.003
- NHS. Constipation. https://www.nhs.uk/conditions/constipation/
Gutsi provides lifestyle and wellness insights only. It is not intended to diagnose, treat, cure or prevent any disease, and should not be used as a substitute for professional medical advice.
