Eating two to three kiwis a day could significantly relieve chronic constipation, according to new research from King’s College London. The findings mark the first time experts have created an official list of foods proven to improve bowel movement.

The newly developed dietary guidelines, endorsed by the British Dietetic Association, are based on extensive scientific evidence and designed to help adults suffering from chronic constipation — a condition that affects millions worldwide and greatly impacts quality of life.

Until now, medical advice largely focused on general suggestions like increasing fiber intake and drinking more water.

However, this latest research provides clear, evidence-based direction on which foods and supplements are truly effective.

Findings from 75 clinical trials

The guidelines are grounded in data from 75 clinical trials, making this one of the most comprehensive analyses to date. Researchers found that consuming two to three kiwis daily for four weeks led to significant improvement in bowel movement frequency and comfort.

In contrast, some long-standing remedies were found to be ineffective. The study highlighted that simply “eating more fiber” may not be enough — the source and type of fiber matter far more for digestive health.

Expert insights and impact

Lead author Dr. Irene Demidy, Reader in Nutritional Sciences at King’s College London, described the findings as a major step forward in tackling a common yet often overlooked health problem.

“Chronic constipation can have a significant impact on a person’s daily life. For the first time, we have provided clear guidance on which foods can really help and which advice is just guesswork,” said Dr. Demidy.

Constipation affects one in six adults, making it one of the leading reasons for medical consultations and use of over-the-counter laxatives. The new research could shift how doctors and dietitians treat the condition — emphasizing personalized dietary approaches rather than one-size-fits-all recommendations.