Remedy · fruit
Kiwifruit for constipation: what the evidence says
Two green kiwifruit a day is one of the best-tested food approaches to constipation, and the gentlest on the gut. The sleep research is small and uncontrolled.
By the editors of Alimentotherapy Last reviewed 3 min read Not medical advice
Kiwifruit
Actinidia deliciosa
Best-supported use: Chronic constipation
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The short answer
Kiwifruit has moderate evidence for constipation: in an international randomized trial two green kiwifruit a day added about 1.5 complete bowel movements a week in people with chronic constipation, and in a US comparison it matched prunes and psyllium with the fewest side effects Gearry 2023; Chey 2021. The evidence that it helps sleep comes from one small study with no control group Lin 2011.
The evidence, use by use
Each claim graded on human studies only. How we grade
| Use | Grade | What the research found |
|---|---|---|
| Chronic constipation | Moderate | Two green kiwifruit a day for four weeks increased complete bowel movements by about 1.5 a week in functional constipation and by about 1.7 in IBS with constipation, and improved gut comfort. A pooled review found fruit, kiwifruit in particular, gave more bowel movements than psyllium. Gearry 2023; Vanderschoot 2024 |
| Bloating and gut comfort with constipation | Limited | In a US trial of 75 analyzed patients, the kiwifruit group reported improved bloating scores and the lowest rate of side effects among kiwifruit, prunes and psyllium. Chey 2021; Gearry 2023 |
| Sleep quality | Limited | In 24 adults with sleep problems who ate two kiwifruit an hour before bed for four weeks, sleep onset and total sleep improved, but the study had no control group. Lin 2011 |
How many, and which kind
The trials are consistent on the dose: two green kiwifruit a day, for four weeksGearry 2023; Chey 2021. Most research used green kiwifruit; a smaller New Zealand trial tested two gold kiwifruit a day for constipation too Bayer 2022.
In the kitchen
Eat them ripe, when they give slightly to the thumb. Halve and scoop with a spoon if you do not like the skin. They pair well with yogurt or oats at breakfast, adding more fiber to the same meal.
If you want to see how two kiwifruit fit your daily fiber total, a fiber-tracking app like Cronometer shows it at a glance.
Why it might work
Nobody has settled why kiwifruit works. The fruit is high in fiber that holds water and softens stool, and researchers have proposed other components too, but the trials on this page measured bowel habits and comfort, not the mechanism Gearry 2023. That is why the grade rests on the outcomes.
Kiwifruit compared with prunes and psyllium
In the US head-to-head trial, all three increased complete bowel movements, and kiwifruit had the fewest side effects and the fewest dissatisfied patients Chey 2021. The 2025 British Dietetic Association guidelines include recommendations on kiwifruit for chronic constipation Dimidi 2025. See prunes, psyllium and the regularity guide.
A note on who paid
Kiwifruit research is partly funded by the industry: the largest multicenter trial lists authors from Zespri, the New Zealand kiwifruit marketer Gearry 2023. That does not make the results wrong, and the US trial and the independent review point the same way, but it is worth knowing.
Before you try it: safety and interactions
Who should avoid it or ask first
- You are allergic to kiwifruit: reactions range from mouth itching to life-threatening anaphylaxis, and kiwifruit is one of the more common fruit allergies.
- You have reacted to other raw fruits before with mouth itching or swelling: ask an allergist before trying kiwifruit regularly.
- You have constipation with severe pain, vomiting, blood in the stool or a sudden change in habit: see a clinician.
Possible side effects
- Mild mouth itching or tingling in some people; this can be a sign of allergy.
Pregnancy and breastfeeding
Kiwifruit is an ordinary food and is fine in pregnancy and breastfeeding unless you are allergic to it. Wang 2019
Medicine interactions
We found no well-documented medicine interactions for kiwifruit at food amounts. That is not proof there are none: tell your pharmacist about any herb or supplement you take.
Check another food or medicine in the interactions list.
Common questions
How many kiwis a day for constipation?
Two green kiwifruit a day for four weeks is the amount tested in the main trials. In a 2023 international randomized trial it added about 1.5 complete bowel movements a week in people with chronic constipation and improved gut comfort.
Is kiwifruit better than prunes or psyllium?
In a 2021 US trial all three improved constipation; kiwifruit caused the fewest side effects and the least dissatisfaction. A 2024 review of food trials found kiwifruit gave slightly more bowel movements per week than psyllium.
Does eating kiwi before bed help you sleep?
The evidence is weak. One study of 24 adults who ate two kiwifruit an hour before bed reported better sleep after four weeks, but it had no comparison group, so the improvement could have had other causes.
Sources
Primary research and government sources, each checked on the date this page was reviewed.
- PubMedGearry R, et al. Consumption of 2 green kiwifruits daily improves constipation and abdominal comfort: results of an international multicenter randomized controlled trial. Am J Gastroenterol. 2023. PMID 36537785.
- PubMedChey SW, et al. Exploratory comparative effectiveness trial of green kiwifruit, psyllium, or prunes in US patients with chronic constipation. Am J Gastroenterol. 2021. PMID 34074830.
- PubMedBayer SB, et al. Two gold kiwifruit daily for effective treatment of constipation in adults: a randomized clinical trial. Nutrients. 2022. PMID 36235798.
- PubMedvan der Schoot A, et al. Systematic review and meta-analysis: foods, drinks and diets and their effect on chronic constipation in adults. Aliment Pharmacol Ther. 2024. PMID 37905980.
- GuidelineDimidi E, et al. British Dietetic Association guidelines for the dietary management of chronic constipation in adults. J Hum Nutr Diet. 2025. PMID 41081513.
- PubMedLin HH, et al. Effect of kiwifruit consumption on sleep quality in adults with sleep problems. Asia Pac J Clin Nutr. 2011. PMID 21669584.
- PubMedWang J, et al. A comprehensive review on kiwifruit allergy: pathogenesis, diagnosis, management, and potential modification of allergens through processing. Compr Rev Food Sci Food Saf. 2019. PMID 33336949.
Keep reading
- GoalFood for regularity: fiber, fluids, kiwifruit and prunesMost adults eat well under the fiber they need. Raising it slowly, with fluid, is the first step; kiwifruit, prunes and psyllium all have trial support.
- RemedyPrunesThe old remedy holds up: in trials, a daily handful of prunes improved constipation about as well as a fiber supplement. Research on bone density is early.
- RemedyPsylliumThe seed husk sold as a bulk fiber. It has the best evidence of any fiber supplement for chronic constipation and a solid record on LDL cholesterol.
- GoalFood and sleep: what the evidence saysThe biggest food levers for sleep are what you stop: caffeine in the afternoon and alcohol near bedtime. Bedtime foods and drinks have small, uncertain effects.