On The Shelf
Mickie Cathers
Constipation is associated with reduced quality of life for about 10% of the worldwide population, and GI discomfort affects many. Patients seeking medical care through current pharmacological treatments or OTC supplements can’t always tolerate fiber supplements, laxatives, or bulking agents, and most of these approaches lack robust scientific evidence supporting their efficacy. However, a recent study offers significant evidence of the beneficial effect of green kiwifruit for GI function and comfort.
Does it work?
Several studies have shown that consumption of green kiwifruit leads to improved bowel movements in constipated patients and improves measures of GI comfort, including bloating. A growing body of evidence supports consumption of certain foods such as psyllium and green kiwifruit to reduce abdominal pain and improve GI discomfort, supporting the concept that dietary interventions can have an impact beyond simple nutrition. Both green kiwifruit and psyllium are well known as beneficial treatments for constipation and bowel habit normalization.
The mechanism of action for kiwifruit and psyllium husk in improving laxation and abdominal comfort boils down to fiber. The fiber in kiwifruit cell walls has a large capacity to hold water, which can lead to stool softening and increased stool frequency. Kiwifruit also has raphides (also found in pineapple, spinach, and agave), needle-shaped crystals of calcium oxalate monohydrate that may alter mucin production and lead to improved bowel movements.
Kiwifruit improves constipation
A June 2023 international multicenter randomized controlled trial published in the American Journal of Gastroenterology found that consumption of kiwifruit was associated with a clinically relevant increase in complete spontaneous bowel movements (CSBM) per week. Gearry and colleagues reported that kiwifruit also significantly improved measures of GI comfort in patients with constipation with no significant adverse effects.
This prospective, single-blinded, crossover 16-week trial included three diverse adult populations. Participants from New Zealand, Italy, and Japan with irritable bowel syndrome with predominant constipation (IBS-C) or functional constipation (FC), along with healthy controls were randomized to consume either two green kiwifruits or 7.5 g of psyllium over the course of 4 weeks as bowel habit and GI comfort were measured. Study authors assessed the effect of daily consumption of two green kiwifruits on normalization of bowel habit and measures of GI comfort. Both the kiwifruits and the psyllium provided approximately 6 g of dietary fiber, and the psyllium was used as a positive control. Participants were not instructed to change their habitual diet beyond the intervention over the study period or given guidance on daily time or occasion for consumption.
Primary outcome was the number of CSBMs per week; key secondary outcomes included GI comfort measured with a GI symptom rating scale, stool consistency, and degree of straining. IBS-associated quality of life was assessed by a questionnaire at the end of each study period as well as reviews to determine changes in mood.
Study results revealed that both interventions—kiwifruit and psyllium—resulted in significant and sustained increases in the weekly frequency of CSBMs in all study groups. Daily consumption of two green kiwifruits produced a significant reduction, compared to baseline, in overall GI symptoms, as determined by the total score for FC, IBS-C, and the combined FC plus IBS-C group. Consumption of psyllium was associated with a significant reduction in GI symptoms in the IBS-C group only.
What to tell your patients
Daily consumption of two green kiwifruits is considered safe, effective, and well-tolerated to increase CSBM and as a beneficial treatment for constipation and abdominal and GI discomfort. ■