Chronic constipation - which food is best?

By Sascha McMeekin, Accredited Practising Dietitian, Owner and Principal Dietitian at Prosper Dietetics

If you are battling chronic constipation this article is for you. Most likely, this disorder is costing you considerable time and money and detracting from your enjoyment of life. You aren’t alone with approximately 10% of the global population with the same struggle. You have most likely adjusted your diet and lifestyle to improve your chronic constipation with little relief or satisfaction. Until recently, even the most common diet and lifestyle changes had not been compared and assessed with a rigorous scientific lens. Leaving chronic constipation sufferers like yourself, and even dietitians, without clear guidance about the best management options.

Dr Eirini Dimidi, Dietitian Researcher, has solved this problem with support from the British Dietetic Association. Dr Dimidi and her team, have published the ‘British Dietetic Association Guidelines for the Dietary Management of Chronic Constipation in Adults’ in the Journal of Human Nutrition and Dietetics. The findings of this research have revealed which food is best food for constipation. This is very rare in the dietetics world. Nutrition research rarely, if ever, leads to a single food recommendation for a condition. Please be aware this article is no replacement for a medical or dietetics assessment where the underlying cause for constipation can be identified and a comprehensive management plan can be formulated.

To begin, how do you know if you have chronic constipation?

Constipation is diagnosed based on your symptoms. Your GP will ask you about the frequency and consistency of your stools and how easily they pass. Your answers will allow them to determine whether you meet the diagnostic criteria for functional constipation, or whether you may be suffering from another condition and potentially require further investigations.

Once you have a diagnosis, what next?

Almost all sufferers of chronic constipation have made changes to their diet and lifestyle to try to improve their symptoms, often without success. One of the most common changes people make is to increase the high fibre food in their diet. More fibre, more bulk, more regularity you might think. This is, in part, correct. However, there is more to the picture.

As this diagram shows, increasing fibre in the gut does in fact increase stool mass and speed up transit time – both good news for constipation sufferers. However, if this dietary change is not carefully managed, it can lead to abdominal pain, bloating and increased wind leaving you more uncomfortable than before you started. Consulting with a specially trained gut health Dietitian can help you navigate this process.

Are fibre supplements better than increasing fibre from whole foods?

Are fibre supplements a better solution to manage chronic constipation than eating more high fibre foods? As it stands, there is more evidence supporting the use of fibre supplements for chronic constipation than following a ‘high fibre diet’. (There are, however, several limitations with the high fibre diet research, so perhaps well designed studies in the future will lead to a different outcome. For overall health, diversifying the sources of fibre in your diet, i.e. increasing the number of plant foods you eat, is highly recommended). Fibre supplements can be a convenient method of increasing your fibre intake, in a measured and systematic way. Research shows that not all fibre supplements are equal when it comes to managing chronic constipation. Dr Dimidi’s research has revealed that if introduced correctly, psyllium husks compared to other fibre supplements are best for improving stool frequency, stool consistency and reduce severity of straining. Your Dietitian will be happy to advise you on the particulars.

Which food is best for constipation?

Most often, people like you with chronic constipation would rather add in a real food than take a supplement or change their whole diet. It is far easier and more sustainable. And has the added benefit of improving your overall health while managing constipation. If this option is best for you, then the food to add into your diet is - the humble kiwi fruit. Dr Dimidi’s analyses revealed that eating the right dose of kiwi fruits for the correct duration of time was more effective than psyllium husk fibre supplements for chronic constipation with less wind and bloating. They contain a unique enzyme called actinidin which improves bowel motility and breaks down proteins. In addition, kiwi fruits are a great source of fibre, vitamin C, vitamin K and antioxidants.

If you would like advice about how to manage your chronic constipation, Sascha would be delighted to help you. You can visit the booking page here.  

Sascha has developed her specialisation in managing IBS and gut health over the past 15 years. She is an Accredited Practising Dietitian and a Monash Certified FODMAP Dietitian. Her priority is always to provide the highest quality of clinical care. That means recommendations based on science and in way that considers your individual needs, goals and lifestyle. Calm, qualified advice to bring you real improvements to your health and wellbeing.

For more of the latest nutrition advice for IBS visit Sascha on Instagram @ibs.gut.dietitian.

Reference

Dimidi E. Dietary management of chronic constipation: a review of evidence-based strategies and clinical guidelines. Proc Nutr Soc. 2025 Dec;84(4):398-410. doi: 10.1017/S0029665125100694. Epub 2025 Sep 1. PMID: 40888045.