Researchers at King’s College London have developed the first evidence-based dietary guidelines for adults with chronic constipation, identifying specific foods and supplements that may help improve symptoms. The findings were published in the Journal of Human Nutrition & Dietetics and Neurogastroenterology & Motility and are endorsed by the British Dietetic Association.

According to the guidelines, consuming kiwifruits, rye bread, and high mineral-content water could alleviate chronic constipation. The study also found that psyllium fibre supplements, certain probiotic strains, and magnesium oxide supplements may be effective. In contrast, other commonly recommended approaches, including generic high-fibre diets and senna supplements, were found to have limited supporting evidence.

The research team applied the GRADE framework to evaluate the strength of evidence from more than 75 clinical trials, resulting in 59 dietary recommendation statements and 12 research priorities. Dr Eirini Dimidi, lead author and Reader in Nutritional Sciences at King’s College London, said: “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.”

The study highlights the need for improved nutrition research, noting that most existing trials focus on single interventions rather than comprehensive dietary patterns. Dr Dimidi added, “Eating a high fibre 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.”

Professor Kevin Whelan, senior author and Professor of Dietetics at King’s College London, said: “This means that from now that, 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 wellbeing.”

The guidelines aim to assist health professionals and patients in managing constipation through diet while emphasising the need for further high-quality studies to validate and expand upon these findings.

Source: KCL