Am J Gastroenterol. 2023 Jun 1;118(6):1058-1068.doi: 10.14309/ajg.0000000000002124. Epub 2022 Dec 20.

Richard Gearry ¹, Shin Fukudo ^2 3, Giovanni Barbara ⁴, Barbara Kuhn-Sherlock ⁵, Juliet Ansell ⁶, Paul Blatchford ⁶, Sarah Eady ⁷, Alison Wallace ⁷, Christine Butts ⁷, Cesare Cremon ⁴, Maria Raffaella Barbaro ⁴, Isabella Pagano ⁴, Yohei Okawa ², Tomohiko Muratubaki ², Tomoko Okamoto ⁸, Mikiko Fuda ⁹, Yuka Endo ³, Michiko Kano ², Motoyori Kanazawa ^2 3, Naoki Nakaya ¹⁰, Kumi Nakaya ¹⁰, Lynley Drummond ¹¹

Author information

¹Department of Medicine, University of Otago, Christchurch, New Zealand.

²Department of Behavioral Medicine, Tohoku University Graduate School of Medicine, Sendai, Japan.

³Department of Psychosomatic Medicine, Tohoku University Hospital, Sendai, Japan.

⁴Department of Medical and Surgical Sciences, University of Bologna, Bologna, Italy.

⁵BKS Consulting Limited, Hamilton, Waikato, New Zealand.

⁶Zespri International Limited, Tauranga, New Zealand.

⁷The New Zealand Institute for Plant and Food Research Limited, Palmerston North and Christchurch, New Zealand.

⁸Department of Nutrition, Sapporo University of Health Sciences, Sapporo, Japan.

⁹Department of Clinical Nutrition, Tohoku University Hospital, Sendai, Japan.

¹⁰Department of Preventive Medicine and Epidemiology, Tohoku Medical Megabank Organization, Tohoku University, Sendai, Japan.

¹¹Drummond Food Science Advisory Limited, Killinchy, Canterbury, New Zealand.

Abstract

Introduction: Consumption of green kiwifruit is known to relieve constipation. Previous studies have also reported improvements in gastrointestinal (GI) comfort. We investigated the effect of consuming green kiwifruit on GI function and comfort.

Methods: Participants included healthy controls (n = 63), patients with functional constipation (FC, n = 60), and patients with constipation-predominant irritable bowel syndrome (IBS-C, n = 61) randomly assigned to consume 2 green kiwifruits or psyllium (7.5 g) per day for 4 weeks, followed by a 4-week washout, and then the other treatment for 4 weeks. The primary outcome was the number of complete spontaneous bowel movements (CSBM) per week. Secondary outcomes included GI comfort which was measured using the GI symptom rating scale, a validated instrument. Data (intent-to-treat) were analyzed as difference from baseline using repeated measures analysis of variance suitable for AB/BA crossover design.

Results: Consumption of green kiwifruit was associated with a clinically relevant increase of ≥ 1.5 CSBM per week (FC; 1.53, P < 0.0001, IBS-C; 1.73, P = 0.0003) and significantly improved measures of GI comfort (GI symptom rating scale total score) in constipated participants (FC, P < 0.0001; IBS-C, P < 0.0001). No significant adverse events were observed.

Discussion: This study provides original evidence that the consumption of a fresh whole fruit has demonstrated clinically relevant increases in CSBM and improved measures of GI comfort in constipated populations. Green kiwifruits are a suitable dietary treatment for relief of constipation and associated GI comfort.

Trial registration: ClinicalTrials.gov NCT02888392