Researchers at King's College London have developed the first evidence-based dietary guidelines for managing chronic constipation in adults. The recommendations highlight kiwifruit, rye bread, and mineral water as helpful, while questioning the benefits of general high-fiber diets. Supplements like psyllium, probiotics, and magnesium oxide also show promise.
Chronic constipation affects quality of life and healthcare costs, yet previous advice often focused simplistically on increasing fiber and fluids. Now, experts have created comprehensive guidelines based on rigorous evidence, marking a shift toward more targeted dietary strategies.
The guidelines, published in the Journal of Human Nutrition & Dietetics and Neurogastroenterology & Motility, were endorsed by the British Dietetic Association. An expert panel—including dietitians, a nutritionist, gastroenterologist, gut physiologist, and general practitioner—reviewed data from over 75 clinical trials using the GRADE framework for evidence quality. This resulted in 59 recommendations across 12 key areas, emphasizing measurable outcomes like stool frequency, consistency, straining, and quality of life.
Key findings point to kiwifruit, rye bread, and mineral-rich water for relief, alongside supplements such as psyllium fiber, certain probiotics, and magnesium oxide. In contrast, popular approaches like high-fiber diets and senna laxatives lack sufficient scientific support for constipation specifically.
Dr. Eirini Dimidi, lead author and Reader in Nutritional Sciences at King's College London, stated: "Chronic constipation can have a huge impact on someone's day-to-day life. For the first time, we've provided direction on what dietary approaches could genuinely help, and which diet advice lacks evidence. Being able to improve this condition through dietary changes would allow people to self-manage their symptoms more and, hopefully, improve their quality of life."
She added: "Eating a high fiber diet offers many benefits to overall health and has been a go-to recommendation for constipation. However, our guidelines found that there simply isn't enough evidence to suggest it actually works in constipation specifically. Instead, our research reveals some new dietary strategies that could indeed help patients. At the same time, we urgently need more high-quality trials to strengthen the evidence on what works and what doesn't."
Professor Kevin Whelan, senior author and Professor of Dietetics, noted: "This new guidance marks a promising step towards empowering health professionals and their patients to manage constipation through diet. This means that from now on people suffering from constipation across the world can now receive up-to-date advice based upon the best available evidence in order to improve their symptoms and well-being. With continued research, it holds real potential to drive lasting improvements in quality of life."
The guidelines include a clinician-friendly tool for global use, promoting personalized nutrition while calling for better research on comprehensive diet patterns.