Study Type Daily Amount Tested Key Outcome Comparison
Randomized trial ~50g (5–6 prunes) Increased bowel movement frequency and better consistency More effective than psyllium
Prune juice trial ~200ml Reduced hard stools after 3 weeks Placebo-controlled
Chronic constipation review 80–120g Higher stool weight and more complete movements General fiber sources
Meta-analysis 100g Superior relief compared to many fiber supplements Various interventions
Sources include journals like Alimentary Pharmacology & Therapeutics and The American Journal of Clinical Nutrition. Effects typically begin within a few days and strengthen over 2–4 weeks. Most participants report good tolerance with minimal side effects when starting gradually.
The truth is, prunes often outperform psyllium (a popular fiber supplement) in head-to-head studies for both frequency and comfort. That’s something many people don’t expect from a simple dried fruit.
How Many Prunes Should You Try?
