By Joke Kujenya
FRESH DIETARY recommendations from the British Dietetic Association (BDA) have highlighted specific foods and supplements that can help reduce symptoms of chronic constipation, a condition affecting nearly 16% of adults worldwide.
Constipation, which involves fewer than three bowel movements per week, becomes chronic when it persists for more than three months.
According to health authorities, symptoms range from hard or lumpy stools to abdominal pain and nausea. Severe cases may include blood in the stool, fever, or vomiting.
The condition, caused by factors such as poor diet, low fibre intake, dehydration, inactivity, or certain medications, affects people across all age groups.
“I see chronic constipation across the spectrum,” said Sue-Ellen Anderson-Haynes, a registered dietitian and spokesperson for the Academy of Nutrition and Dietetics. “I see it in toddlers, I see it in school-age children, I see it in adults. So it’s a common thing,” she said.
According to Anderson-Haynes, chronic constipation can severely affect people’s quality of life, limiting daily activities and reducing productivity.
“If you’re chronically constipated, you may not be able to even participate in physical activity, because you feel bloated, you’re in pain, you’re achy, it may affect your mood,” she added.
The American College of Gastroenterology has noted that constipation leads to approximately 2.5 million medical visits in the United States annually.
The National Health Service (NHS) identifies common causes including low fibre intake, inadequate hydration, limited movement, stress, and certain medicines.
The BDA’s newly released guidelines, described as the first evidence-based dietary recommendations for treating constipation without medication, suggest that certain foods and supplements such as kiwis, rye bread, fibre supplements, probiotics, and magnesium oxide—can improve bowel health.
Eirini Dimidi, lead author of the guidelines and an associate professor in the Department of Nutritional Sciences at King’s College London, stated that existing management approaches focus heavily on pharmaceuticals rather than diet.
“I remember looking at the guidelines and realising that they are just really limited in the number of dietary recommendations they make,” Dimidi explained.
The new recommendations, published in the Journal of Human Nutrition & Dietetics and Neurogastroenterology & Motility, followed a comprehensive review of clinical trials assessing the effectiveness of various dietary strategies in managing chronic constipation.
Dr William Chey, a professor of gastroenterology at the University of Michigan and incoming president of the American College of Gastroenterology, said that most prior studies on constipation management have centred on fibre supplements, such as psyllium, and medications like bisacodyl, senna, and amitiza.
Traditional treatment approaches often involve increasing fibre through foods such as prunes, fruits, and vegetables, alongside increased water intake and use of laxatives.
While the BDA’s recommendations include some of these options, Dimidi noted the lack of strong scientific evidence supporting the broader concept of a “high-fibre diet” as a standalone remedy for constipation.
“When we were building these guidelines and looking at the literature, we were expecting a lot more evidence on a high-fibre diet, and there simply isn’t enough in constipation,” Dimidi said.
“There’s plenty of evidence that a high-fibre diet is very beneficial for our overall health and for elements of gut health, such as reducing the risk of colorectal cancer, but when it comes to constipation specifically, we just don’t have enough evidence to say that it improves constipation.”
The BDA’s updated dietary guidance outlines several key evidence-backed recommendations:
Fibre supplements: The intake of more than 10 grams of fibre supplements, such as psyllium, per day can improve stool frequency and consistency and reduce straining.
The BDA advises that supplements should be introduced gradually to allow the digestive system to adjust.
Probiotics: Certain strains, including Bifidobacterium lactis and Bacillus coagulans Unique IS2, may help some individuals with symptoms.
The guidance recommends using a supplement of choice and following the manufacturer’s instructions for a minimum of four weeks.
Magnesium oxide supplements: Doses between 0.5 and 1.5 grams per day can enhance stool frequency and consistency, relieve bloating and abdominal discomfort, and improve quality of life. The dosage should start at 0.5 grams daily and be increased weekly.
Kiwis: Consuming three kiwis per day, with or without skin, may improve stool frequency.
Rye bread: Eating six to eight slices of rye bread daily may aid bowel movement frequency, although the authors acknowledge this amount may be impractical for some people.
High mineral-content water: Drinking 0.5 to 1.5 litres of water with a high mineral content per day, in combination with other treatments, can assist bowel movements. Magnesium, a key mineral in such water, acts as a natural laxative.
Dr Chey, however, noted the variability in the effectiveness of probiotics. “People’s microbiomes vary a lot from location to location based on diet, genetics, and environment, and so it’s very hard to make any generalisable statements about the use of specific probiotics,” he said.
Despite this, he acknowledged that the new dietary framework represents a significant step forward in addressing constipation through non-pharmaceutical approaches.
“I think these kinds of recommendations are going to be very helpful,” he stated.
Dimidi also expressed optimism that the publication of the guidelines will improve clinical practice and empower individuals living with chronic constipation.
“We’re hoping the guidance means that clinicians are well-informed and can provide personalised advice to their patients that is very effective,” she said.
“But also that people themselves with constipation can access evidence-based information, feel empowered to take control of the symptoms, and improve a condition that has a tremendous impact on quality of life.”
Health professionals further note that while chronic constipation can be difficult to manage, dietary changes, adequate hydration, and lifestyle adjustments remain among the most effective long-term solutions.
They said the new BDA guidelines mark an important shift towards more targeted, evidence-based dietary approaches to one of the most widespread digestive disorders worldwide.
