Do prunes and prune juice help with constipation?

Probably, a little, and on far less evidence than the reputation suggests. The British Dietetic Association pooled the 2 randomized trials of whole prunes in 86 people with chronic constipation in 2025. Prunes softened stools no more than psyllium did, a difference of 0.45 points on the Bristol stool scale with an interval from minus 0.24 to 1.14, and the certainty was very low. For prune juice there is one placebo-controlled trial, in 84 Japanese adults with chronic constipation, where 54 g a day cut hard and lumpy stools from the third week of 8.

Unsettled. Every whole-prune trial compared prunes with psyllium, which is itself an effective treatment. Those trials were not built to show the two are equal, so the guideline says it is not possible to conclude prunes work as well as psyllium. We did not find a trial of whole prunes against placebo in constipation. That missing trial is why the answer is probably rather than yes.

What the trials found

Whole prunes against psyllium

The trial behind most claims ran in 40 constipated adults, 37 of them women, mean age 38. Each person spent 3 weeks on 1.8 oz (50 g) of dried plums twice a day and 3 weeks on 11 g of psyllium twice a day, matched for fiber, with a week's break between. On prunes they had 3.5 complete bowel movements a week against 2.8 on psyllium, and stools were a little softer, 3.2 against 2.8 on the Bristol scale. Straining and overall symptoms did not differ. It was single-blind and small, and it says nothing about prunes against doing nothing.

Pooling changed the picture. A 2024 meta-analysis of foods for chronic constipation, 23 studies and 1,714 people, found fruit raised stool frequency over psyllium by 0.36 bowel movements a week, almost all of it from kiwifruit. For the two prune trials it found no difference from psyllium. A 2021 systematic review of over-the-counter treatments graded prune-based laxatives B, and that grade rests on the same single trial of 40 patients.

Prune juice against placebo

In a double-blind trial, 84 Japanese adults aged 20 to 75 with untreated chronic constipation drank 1.9 oz (54 g) of prune juice or a flavor-matched placebo every day for 8 weeks, 42 per group. From the third week the prune group had significantly fewer hard and lumpy stools, and loose stools did not rise. The paper shows the result as rates in figures, with no single effect size, and it is one trial. It is still the only placebo-controlled test of prunes in any form that we found.

Prunes in people who are not constipated

In 120 healthy London adults with low fiber intake and 3 to 6 stools a week, 2.8 oz (80 g) of prunes a day for 4 weeks added 22.2 g of stool a day, with an interval from minus 1 to 45.3 g, and 120 g a day added 32.8 g, from 13.9 to 51.7 g. The control group changed by minus 0.8 g. Gut transit time did not change. In a 2-week crossover pilot of 26 women aged 25 to 54, not selected for constipation, 100 calories of dried plums twice a day gave softer stools than usual eating or low-fat cookies. That pilot reports no effect size.

One more trial is often cited for prunes and cannot carry the claim. In 43 older adults with mild constipation, mean age 76, a yogurt with galacto-oligosaccharides, 12 g of prunes and linseed raised bowel movements to 8.0 a week against 7.1 on a control yogurt over 3 weeks. Prunes were one of three active parts, at a small dose, and the yogurt maker funded the trial.

Who should be careful

In the trials prunes were well tolerated. The 2021 review found fruit-based laxatives, prunes included, caused few mild gut complaints or none, in trials of about 4 weeks that could not show rare or long-term harm. In the 84-person juice trial there were no adverse events and no liver or kidney abnormalities in either group over 8 weeks. The one downside measured was wind: in the 120-person dose trial, flatulence was significantly more common on prunes.

Not for everyone. Three groups have a reason to go carefully, and all three run through sorbitol, a poorly absorbed sugar alcohol in prunes. None of these studies gave prunes, and we did not find the sorbitol content of a prune serving in a primary source. In a double-blind challenge, 10 g of pure sorbitol raised gut symptoms in 20 people with irritable bowel syndrome and not in 21 healthy people. In 104 healthy children aged 1 to 5, one serving of sorbitol-rich pear juice was incompletely absorbed in 84% against 20 to 24% for sorbitol-free grape juice, and 6 children had diarrhea after it. Prune juice was not tested there. For hereditary fructose intolerance, all 15 Italian metabolic centers surveyed in 2026 class sorbitol as prohibited, which is a practice survey rather than an outcome study.

We found no trial of prunes or prune juice in children or in pregnancy. For a constipated child, the amount and the choice of remedy are a question for the child's doctor. We also did not review prunes for people told to limit potassium, such as some people with kidney disease, so this page cannot say what amount is safe for them. That is a question for their kidney team.

What expert bodies say

The British Dietetic Association, in its 2025 guideline, makes no claim that prunes match psyllium and asks for placebo-controlled trials. The European Union authorizes one claim, that dried prunes contribute to normal bowel function, and only for food that provides 3.5 oz (100 g) of prunes a day, with the label stating that amount. A dried prune weighs about 8 g in the USDA portion table, so that is roughly 12 prunes. The EU refused every bowel claim submitted for prune juice. That refusal concerned the juice as submitted in 2010, and it measured no effect either way.

How we searched

What would change this answer

• A placebo-controlled trial of whole prunes in people with chronic constipation. The guideline asks for it, and none exists that we could find.
• A trial registered as NCT06963125 is giving 90 older adults 100, 150 or 6.8 fl oz (200 mL) of prune juice a day, with completion due in November 2026. It would be the first dose-response data for juice in older people.
• Any trial of prunes or prune juice in children or in pregnancy, two groups for whom prune juice is commonly suggested and for whom we found no trial at all.

For what else prunes do and do not do, see the prunes page and the prune juice page.

Sources

1. ev-prn-01 · Meta-analysis or systematic review · GRADE guideline built on systematic reviews and meta-analyses of RCTs · n = 86
   Two RCTs, including 86 people with chronic constipation, assessed the effect of prunes on stool consistency only and were meta‐analysed [ 14 ]. Overall, prunes had no greater impact on stool consistency compared to psyllium supplements (MD: +0.45 points in the Bristol Stool Form Scale, 95% CI: −0.24, 1.14 points).
   
   Who: Adults with chronic constipation, 2 RCTs of prunes vs psyllium
   Effect: stool consistency MD +0.45 Bristol points (95% CI -0.24 to 1.14); straining severity SMD -0.13 (95% CI -0.69 to 0.43), 89 people
   Certainty: Both prune statements graded very low and qualified (high risk of bias, imprecision). The comparator is psyllium, an effective treatment, so 'no difference' is not 'no effect'.
   J Hum Nutr Diet, 2025 · checked 2026-10-06 · we read the fulltext
2. ev-prn-02 · Position of an expert body · research recommendation within a GRADE dietary guideline · n = —
   Psyllium is itself an effective treatment for chronic constipation. However, these studies did not follow a truly comparative evaluation design in that studies were not equivalence trials; hence, it is not possible to conclude that prunes are as effective as psyllium.
   
   Who: Guideline research recommendation for adults with chronic constipation
   Effect: no recommendation for or against prunes as equivalent to psyllium; research gap stated
   Certainty: A statement about the design of the evidence, not a measured effect.
   J Hum Nutr Diet, 2025 · checked 2026-10-06 · we read the fulltext
3. ev-prn-03 · Meta-analysis or systematic review · systematic review of randomized controlled trials with USPSTF grading, no meta-analysis · n = 40
   Prunes were associated with significantly greater improvements in mean CSBMs per week (primary outcome) and stool consistency compared with psyllium in 40 patients with chronic constipation (44).
   
   Who: RCTs of at least 4 weeks in chronic constipation, 2004 to 2020, 41 trials; prunes 1 trial of 40 patients
   Effect: prunes improved CSBM per week and stool consistency vs psyllium; Level II evidence, grade B; few mild GI adverse events
   Certainty: Grade B for prunes is built on a single small single-blind trial against psyllium (21323688).
   Am J Gastroenterol, 2021 · checked 2026-10-06 · we read the fulltext
4. ev-prn-04 · Meta-analysis or systematic review · systematic review of randomized controlled trials · n = 5 trials
   Fruit-based laxatives were very well tolerated with few (mild GI-related events) or no adverse events reported.
   
   Who: 5 trials of kiwi, mango, ficus and prune preparations in constipation
   Effect: few mild GI-related adverse events or none reported
   Certainty: Trials were small and short (about 4 weeks), so rare or long-term harms would not show.
   Am J Gastroenterol, 2021 · checked 2026-10-06 · we read the fulltext
5. ev-prn-05 · Randomized controlled trial(s) · double-blind randomized placebo-controlled trial, 8 weeks · n = 84
   Subjects were randomly assigned to the prune juice group or placebo group and consumed 54 g of each test food in a day for 8 weeks.
   
   Who: Adults aged 20 to 75 with treatment-naive chronic constipation by Rome IV, 42 per arm
   Effect: rates of hard and lumpy stools (BSFS 1 or 2) significantly lower than placebo after 3 weeks; loose stools unchanged; no adverse events
   Certainty: Single trial, effect shown as rates in figures without a pooled effect size. Flavor-matched placebo, registered UMIN000041384.
   Am J Gastroenterol, 2022 · checked 2026-10-06 · we read the fulltext
6. ev-prn-06 · Randomized controlled trial(s) · double-blind randomized placebo-controlled trial, 8 weeks · n = 84
   During the study period, there were no AEs or laboratory abnormalities of liver or renal function based on the Common Terminology Criteria for Adverse Events definition between baseline and postintake period in either group (Table 1).
   
   Who: 84 adults with chronic constipation, prune juice or placebo
   Effect: 0 adverse events by CTCAE v5.0 in either group
   Certainty: Small sample over 8 weeks.
   Am J Gastroenterol, 2022 · checked 2026-10-06 · we read the fulltext
7. ev-prn-07 · Randomized controlled trial(s) · randomized double-blind crossover trial · n = 43
   During the test yoghurt period, defecation frequency was higher (8.0 vs 7.1 times/week, P=0.011), defecation was easier (on the scale 0-3, 1.3 vs 1.5, P=0.010), and there was a tendency towards softer stools (on the scale 0-3, 2.1 vs 2.2, P=0.059) compared with the control yoghurt period.
   
   Who: 43 elderly free-living subjects with self-reported constipation, mean age 76
   Effect: defecation frequency 8.0 vs 7.1 times/week (P = 0.011), easier defecation 1.3 vs 1.5 (P = 0.010)
   Certainty: Prunes were one of three active parts at only 12 g a day, so the effect cannot be credited to prunes. Industry funded (Valio).
   Eur J Clin Nutr, 2007 · checked 2026-10-06 · we read the abstract
8. ev-prn-08 · Randomized controlled trial(s) · randomized crossover pilot trial, two 2-week periods · n = 26
   Dried plums promoted a softer (P< or =0.05) stool consistency vs usual intake and in comparison to intake of low-fat cookies.
   
   Who: 26 women aged 25 to 54 with BMI 24 to 35, not selected for constipation
   Effect: softer stool consistency vs usual intake and vs cookies (P <= 0.05)
   Certainty: Pilot, short, people without constipation, no effect size in the abstract.
   J Am Diet Assoc, 2010 · checked 2026-10-06 · we read the abstract
9. ev-prn-09 · Randomized controlled trial(s) · randomized double-blind placebo-controlled crossover challenge · n = 41
   Overall gastrointestinal symptoms increased significantly after both polyols in patients with IBS only, although they were independent of malabsorption of either of the polyols.
   
   Who: 21 healthy and 20 IBS subjects, challenges with 10 g sorbitol, mannitol or glucose
   Effect: overall GI symptoms increased significantly after polyols in IBS only; 40% of IBS and 33% of healthy subjects completely absorbed sorbitol
   Certainty: Pure sorbitol challenge, not prunes. The sorbitol dose in a 100 g prune serving is not given in this source.
   J Hum Nutr Diet, 2014 · checked 2026-10-06 · we read the abstract
10. ev-prn-10 · Randomized controlled trial(s) · randomized single-dose breath hydrogen trial · n = 104
    Incomplete carbohydrate absorption (BH2 peak above 20 ppm) occurred more frequently after pear juice consumption (84%) than after apple juice (41%) or grape juice (white 20%, purple 24%) [p < 0.05].
    
    Who: 104 healthy children aged about 1, 3 and 5 years, one age-specific juice serving
    Effect: incomplete absorption 84% pear vs 41% apple vs 20% and 24% grape (P < 0.05); diarrhea in 6 after pear juice
    Certainty: Prune juice was not tested. Pear juice stands in as a sorbitol-rich juice; the effect faded by age 5.
    J Am Coll Nutr, 1997 · checked 2026-10-06 · we read the abstract
11. ev-prn-11 · Observational data · cross-sectional center-level survey · n = 15 centers
    With regard to sugars and sweeteners, consensus was observed only for maltitol and sorbitol, which were classified as prohibited by all centres (15/15, 100%).
    
    Who: 27 metabolic dietitians across 15 Italian inherited metabolic disease centers
    Effect: sorbitol prohibited by 15/15 centers (100%)
    Certainty: A practice survey, not an outcome study. Prunes are not named in the abstract; the link is through their sorbitol.
    Nutrients, 2026 · checked 2026-10-06 · we read the abstract
12. prun-c3-02 · Meta-analysis or systematic review · systematic review and random-effects meta-analysis of randomized and uncontrolled trials · n = 1714
    We included 23 studies (17 RCTs, 6 uncontrolled; 1714 participants): kiwifruit (n = 7), high-mineral water (n = 4), prunes (n = 2)...Fruits resulted in higher stool frequency than psyllium (MD: +0.36 bowel movements [BM]/week, [0.25-0.48], n = 232), kiwifruits in particular (MD: +0.36 BM/week, [0.24-0.48], n = 192); there was no difference for prunes compared with psyllium.
    
    Who: Adults with chronic constipation, 23 studies and 1714 participants, 2 prune trials
    Effect: fruits vs psyllium MD +0.36 BM/week (95% CI 0.25 to 0.48, n = 232), prunes vs psyllium no difference
    Certainty: Only two prune trials, so the pooled null for prunes is thin. The fruit effect is driven by kiwifruit.
    Aliment Pharmacol Ther, 2024 · checked 2026-09-23 · we read the abstract
13. prun-c3-03 · Meta-analysis or systematic review · systematic review of randomized controlled trials, no meta-analysis · n = 4 trials
    Four trials met the inclusion criteria, one in constipation and three in non-constipated subjects. In constipation, 3 weeks of prune consumption (100 g/day) improved stool frequency (3.5 vs. 2.8 CSBM per week, P = 0.006) and stool consistency (3.2 vs. 2.8 on Bristol stool form scale, P = 0.02) compared with psyllium (22 g/day)...Meta-analysis was not appropriate due to heterogeneity in populations and methods.
    
    Who: Four RCTs, one in constipated adults and three in non-constipated subjects
    Effect: stool frequency 3.5 vs 2.8 CSBM/week (P = 0.006), Bristol score 3.2 vs 2.8 (P = 0.02) vs psyllium 22 g/day
    Certainty: Meta-analysis was judged inappropriate, two trials had unclear risk of bias, and the constipation evidence is one trial.
    Aliment Pharmacol Ther, 2014 · checked 2026-09-23 · we read the abstract
14. prun-c3-04 · Randomized controlled trial(s) · single-blind randomized crossover trial · n = 40
    Subjects received either dried plums (50 g b.d., fibre=6 gm/day) or psyllium (11 g b.d., fibre=6 gm/day) for 3 weeks each, in a crossover trial with a 1-week washout period...Forty constipated subjects (m/f=3/37, mean age=38 years) participated. The number of complete spontaneous bowel movements per week (primary outcome measure) and stool consistency scores improved significantly (P<0.05) with dried plums when compared to psyllium...Dried plums and psyllium were rated as equally palatable and both were safe and well tolerated.
    
    Who: 40 adults with chronic constipation, 37 women, mean age 38, 8-week single-blind crossover
    Effect: CSBM per week and stool consistency improved vs psyllium (P < 0.05), straining and global symptoms not different
    Certainty: Small, single-blind, and the fiber-matched psyllium dose (11 g twice a day) is the comparator, so this says nothing about prunes against no treatment.
    Aliment Pharmacol Ther, 2011 · checked 2026-09-23 · we read the abstract
15. prun-c3-05 · Randomized controlled trial(s) · parallel-group randomized controlled trial, three arms · n = 120
    Subjects were randomised to 80 g/d prunes (plus 300 ml/d water); 120 g/d prunes (plus 300 ml/d water) or control (300 ml/d water) for 4 weeks...There were significantly greater increases in stool weight in both the 80 g/d (mean + 22.2 g/d, 95% CI -1-45.3) and 120 g/d (+32.8 g/d, 95% CI 13.9-51.7) prune groups compared with control (-0.8 g/d, 95% CI -17.2 to 15.6, P = 0.026)...but WGTT was unchanged. The incidence of flatulence was significantly higher after prune consumption.
    
    Who: 120 healthy adults with low fiber intake and 3 to 6 stools a week, London
    Effect: stool weight +22.2 g/d (95% CI -1 to 45.3) at 80 g and +32.8 g/d (95% CI 13.9 to 51.7) at 120 g vs -0.8 g/d control, P = 0.026, transit time unchanged
    Certainty: Healthy volunteers, not patients. Flatulence is the one recorded downside.
    Clin Nutr, 2019 · checked 2026-09-23 · we read the abstract
16. prun-c3-06 · Randomized controlled trial(s) · double-blind randomized placebo-controlled trial · n = —
    Prune intake significantly decreased hard and lumpy stools while increasing normal stool and not increasing loose and watery stools...There were no adverse events or laboratory abnormalities of liver or renal function after prune intake.
    
    Who: Japanese adults with chronic constipation, double-blind placebo-controlled
    Effect: fewer hard and lumpy stools, more normal stools, no increase in loose stools, no adverse events
    Certainty: The abstract reports no sample size, dose or effect size, and no PMC full text was available, so the numbers behind the claim could not be read.
    Am J Gastroenterol, 2022 · checked 2026-09-23 · we read the abstract
17. prun-c3-15 · Position of an expert body · regulatory register entry · n = —
    POL-HC-8372 Dried plums of 'prune' cultivars (Prunus domestica L.) Dried plums/prunes contribute to normal bowel function Authorised
    
    Who: EU register of nutrition and health claims, snapshot of 2026-09-21
    Effect: status Authorised
    Certainty: An authorized claim is a decision on sufficiency of evidence, not a measure of effect size.
    EU Register on nutrition and health claims, claim POL-HC-8372, snapshot 2026-09-21 · checked 2026-09-23 · we read the dataset
18. prun-c3-17 · Position of an expert body · regulatory register entry · n = —
    POL-HC-7843 Prune Juice Prune juice help the maintenance of healthy body function. Prune juice help with the maintenance of health in general Prune juice helps maintain bowel regularity which can help to ensure a healthy digestion and bowel. Prune juice is beneficial to the health of the stomach and digestive system. Prune juice is good for healthy bowel function. Prune juice is good for (regular) digestion Prune juice has a natural laxative effect that can contribute to a healthy digestion and bowel. Non-authorised
    
    Who: EU register of nutrition and health claims, snapshot of 2026-09-21
    Effect: status Non-authorized
    Certainty: The refusal concerns prune juice as submitted in 2010, not whole prunes, for which the same relationship was authorized in 2013.
    EU Register on nutrition and health claims, claim POL-HC-7843, snapshot 2026-09-21 · checked 2026-09-23 · we read the dataset
19. prun-c3-18 · Position of an expert body · binding EU regulation, annex row for dried plums of prune cultivars · n = —
    The claim may be used only for food which provides a daily intake of 100 g of dried plums (prunes). In order to bear the claim, information shall be given to the consumer that the beneficial effect is obtained with a daily intake of 100 g of dried plums (prunes).
    
    Who: Food business operators using the claim on the EU market
    Effect: condition of use: daily intake of 3.5 oz (100 g) of dried plums (prunes)
    Certainty: A legal threshold derived from the EFSA 2012 opinion (EFSA Journal 2012;10(6):2712), which itself returned HTTP 403 and was not read.
    Commission Regulation (EU) No 432/2012 as amended by Regulation (EU) No 536/2013, Annex · checked 2026-09-23 · we read the section
20. prun-c3-20 · Position of an expert body · USDA household measure table, US measures · n = FNDDS 5,432 foods, 22,046 household measures
    FNDDS 2709211 Prune, dried — 1 prune 8 g · 1 cup 160 g · Quantity not specified 40 g
    
    Who: Prune, dried, FNDDS food code 62122100, WWEIA category Dried fruits
    Effect: 1 prune 8 g, 1 cup 160 g, quantity not specified 40 g
    Certainty: Portion weights are US conventions and a cup of prunes is a loose measure. The count of 12 is arithmetic on the 8 g figure, not a measured serving.
    USDA FNDDS 2021-2023, Prune, dried, fdc_id 2709211 · checked 2026-09-23 · we read the dataset