Kiwifruit compared favourably to psyllium in a crossover trial.

In several previous studies, kiwifruit improved symptoms in patients with chronic constipation (NEJM JW Gen Med Jul 15 2021 and Am J Gastroenterol 2021; 116: 1304-1312). For this new clinical trial, researchers in New Zealand, Italy and Japan enrolled 60 patients with functional constipation, 61 patients with constipation-predominant irritable bowel syndrome (IBS-C) and 63 healthy controls. In random order, each participant received a four-week course of two peeled green kiwifruits daily and a four-week course of psyllium (7.5 g daily), separated by a  four-week washout period; both treatments provided about 6 g of fibre daily. The study was funded largely by a company that markets kiwifruit.

The mean number of complete spontaneous bowel movements weekly – the primary outcome – increased by about  1.5 with kiwifruit and about one with psyllium; both increases were statistically significant. Scores on several symptom scales (i.e. addressing constipation, abdominal pain, stool consistency and straining) also tended to improve after both treatments; improvements were somewhat greater with kiwifruit than with psyllium and somewhat greater in patients with IBS-C than in those with functional constipation.

Comment: Patients interested in dietary measures for functional constipation or IBS-C might consider using kiwifruit. The authors describe several physiological properties of kiwifruit – in addition to its fibre content – that could explain its therapeutic effect. However, we do not know whether benefit would be maintained during long-term use or whether patients who benefit would be willing to eat two kiwifruits daily for long periods.

Allan S. Brett, MD, Clinical Professor of Medicine, University of Colorado School of Medicine, Aurora, USA.

Gearry R, et al. Consumption of 2 green kiwifruits daily improves constipation and abdominal comfort – results of an international multicenter randomized controlled trial. Am J Gastroenterol 2023; 118: 1058-1068.

This summary is taken from the following Journal Watch titles: General Medicine, Ambulatory Medicine, Gastroenterology.