GradedHealth

Prunes

Last reviewed October 2026 · Based on 9 studies

Bottom line

Prunes may help preserve bone density in postmenopausal women and ease constipation, but the bone trials are small, the pooled lumbar result is borderline, and no trial has measured actual fractures. Prunes are a food, so the evidence is about eating them, not taking a medicine.

What it helps with

  • Helps preserve bone density — Benefit, evidence grade C (Limited). Small RCTs and one pooled analysis with a borderline lumbar result and high heterogeneity; no effect in men; downgraded for inconsistency and surrogate outcome.
  • Relieves constipation — Benefit, evidence grade C (Limited). Few small trials; one 40-person crossover trial and one sponsored placebo trial; a 2024 meta-analysis found no difference from psyllium; downgraded for small sample and inconsistency.

What it is

Prunes are dried plums, high in fibre [1]. Trials have given 50 g or 100 g a day [2][3].

How it might work

Proposed mechanism: prunes may slow bone breakdown. In one trial, bone-breakdown markers fell in people eating 100 g a day, with no change in the control group [4]. In older women, dried plum reduced a bone-breakdown marker at three months [3].

What the research says

A 2026 meta-analysis of 11 trials (747 people) found a borderline lumbar spine gain, with no clear effect at other sites and high variation between studies [5]. A 12-month trial of 235 women found that 50 g a day preserved total hip bone density (down 0.3%) compared with a 1.1% loss in controls [2]. For constipation, a 2021 review rated prunes as moderate evidence (grade B) [6]. A three-week crossover trial in 40 people found more complete bowel movements per week than psyllium [7]. A 2024 meta-analysis found no difference between prunes and psyllium on stool frequency [8].

Doses used in studies

Bone trials used 50 g or 100 g of prunes a day for 6 to 12 months [2][3][4]. In the constipation crossover trial, prunes were given as 50 g twice a day against psyllium at 11 g twice a day [7].

Safety and interactions

Side effects: prunes were safe and well tolerated in the three-week constipation trial [7], and a prune-juice product reported no adverse events in a placebo-controlled trial [9]. Over-the-counter constipation products commonly cause bloating and abdominal pain, though this review did not single out prunes [6]. Upper intake limits, interactions with medicines, pregnancy and breastfeeding, and kidney disease were not covered by the studies we found, so check those with a doctor or pharmacist.

Caveats and open questions

Bone results rest on small trials and on bone density rather than fractures [5]. Men showed no bone density change in one 12-month trial [4]. Constipation trials are small, and some reviews and trials report links to food or drink makers [6][9].

References

  1. Systematic review: the effect of prunes on gastrointestinal function.. Aliment Pharmacol Ther, 2014.
  2. Prunes preserve hip bone mineral density in a 12-month randomized controlled trial in postmenopausal women: the Prune Study.. Am J Clin Nutr, 2022.
  3. The effect of two doses of dried plum on bone density and bone biomarkers in osteopenic postmenopausal women: a randomized, controlled trial.. Osteoporos Int, 2016.
  4. Effects of 12 Months Consumption of 100 g Dried Plum (Prunes) on Bone Biomarkers, Density, and Strength in Men.. J Med Food, 2022.
  5. Effects of Prunes on Bone Density in Humans: A Systematic Review and Meta-Analysis of Randomized Controlled Trials.. Nutrients, 2026.
  6. Efficacy and Safety of Over-the-Counter Therapies for Chronic Constipation: An Updated Systematic Review.. Am J Gastroenterol, 2021.
  7. Randomised clinical trial: dried plums (prunes) vs. psyllium for constipation.. Aliment Pharmacol Ther, 2011.
  8. Systematic review and meta-analysis: Foods, drinks and diets and their effect on chronic constipation in adults.. Aliment Pharmacol Ther, 2024.
  9. Prune Juice Containing Sorbitol, Pectin, and Polyphenol Ameliorates Subjective Complaints and Hard Feces While Normalizing Stool in Chronic Constipation: A Randomized Placebo-Controlled Trial.. Am J Gastroenterol, 2022.