Where does this news come from?
Constipation or constipation is common, especially in women and the elderly. Because the stool stays longer in your large intestine, more moisture is extracted. This results in dry and hard stools.
Kiwis have been known for years as an aid to difficult bowel movements or constipation. An international team of researchers investigated whether eating kiwi fruit regularly can help with constipation (1):
- The scientists selected 3 groups:
- 63 healthy adults as a control group
- 60 adults with constipation
- 61 adults with constipation and an irritable bowel
- For 4 weeks, the participants received daily:
- either 2 kiwis;
- or a comparable amount of dietary fiber.
- With questionnaires, the researchers recorded:
- the frequency of the participants’ bowel movements;
- she comfort.
The team of scientists found that:
- bowel movement frequency increased by 1.5 per week in the constipated group;
- participants’ comfort increased by less than 1 point on a scale of 1 to 15.
The researchers conclude that kiwis can help against constipation.
Bron
(1) Gearry R, Fukudo S, Barbara G, 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 Jan 9.
How should you interpret this news?
To get straight to the point, this study was fully funded by Zespri International, the major kiwifruit distributor (2).
Apart from that, a few things went wrong for the researchers during the study:
- The majority of the 5 questionnaires yielded no results.
- Little to no difference was found between the kiwifruit and dietary fiber.
- Fifteen people dropped out of the study early.
EFSA, the European Food Safety Authority, has allowed Zespri to state that ‘eating green kiwifruit contributes to normal bowel movements’ (3). The question is, of course, whether specific kiwis are better for relieving constipation, compared to other fruits. In a literature review, researchers found that eating fruit in general can improve your bowel movements (4).
What is remarkable about the Zespri study is that the company claims to have played no role in the design of the study. But one of the researchers responsible for setting up the study turns out to work for Zespri International.
Finally, perhaps nice to know: Chinese researchers found that kiwi berries can relieve constipation in mice (5).
Conclusion
Researchers found that two kiwis a day can relieve the symptoms of constipation. But there were few differences between the effect of kiwifruit and that of dietary fiber in the study. Other research shows that fruit in general can help with constipation. However, EFSA, the European Food Safety Authority, has allowed Zespri to claim specifically that ‘green kiwifruit can contribute to a normal bowel movement’.
