A recent study published in The Lancet Gastroenterology & Hepatology suggests that dietary changes may be more effective than medication in treating irritable bowel syndrome (IBS).
Changing your diet can alleviate symptoms of irritable bowel syndrome (IBS). One diet is designed to be low in "FODMAPs" – a group of sugars and similar carbohydrates found in dairy, wheat, and certain fruits and vegetables. The second is a less common approach for IBS – an adaptable low-carbohydrate diet high in fiber but low in all other types of carbohydrates, namely sugars and starches.
In a randomized trial, both diets improved symptoms better than standard drug therapy after 4 weeks.
IBS causes a range of perplexing symptoms, including diarrhea, constipation, bloating, and abdominal pain, which can vary in intensity over time. The root cause of this condition remains unclear.
Typical advice includes avoiding common triggers like caffeine, alcohol, or spicy foods. Symptomatic relief options include taking laxatives for constipation or medications for diarrhea.
If these measures don't work, people can also try reducing foods high in FODMAPs, which are believed to cause bloating and diarrhea as they often go undigested before reaching the colon. This leads to water retention in the colon and gas production as bacteria consume the molecules, resulting in bloating.
Researchers led by Sanna Nybacka from the University of Gothenburg in Sweden wanted to see how a conventional low FODMAP diet stacked up against a low-carbohydrate approach while still consuming plenty of fiber. In practice, this meant eating high-fat and high-protein foods like meats and dairy, with fiber sources including nuts, seeds, legumes, and vegetables like cabbage.
The study team asked around 300 IBS patients to choose one of three approaches: medication based on symptoms or one of the two diets. For the dietary approaches, participants received detailed meal plans and recipes.
After a month, 76% of the low FODMAP group reported significant symptom relief, compared to 71% in the low-carbohydrate diet group and 58% in the medication group.
Nybacka noted that surprisingly, the low-carbohydrate, high-fiber diet that didn't exclude FODMAP-containing foods was just as effective as the low FODMAP diet. "We can't answer why this is. It seems changing the amount of carbohydrates and reducing FODMAP intake might be beneficial."
However, Hazel Everitt from the University of Southampton in the UK suggested that the effectiveness might improve with longer trials. "Many proposed IBS diets suffer from being hard to maintain long-term."
Participants were followed up for up to 6 months, with those initially receiving drug therapy also receiving dietary advice in the final 5 months.
Nybacka mentioned a potential issue with the low-carbohydrate, high-fiber diet being a slight increase in blood cholesterol levels in this group. Therefore, consulting a doctor before adopting this diet is advisable.
Related paper information: https://doi.org/10.1016/S2468-1253(24)00045-1
