Low FODMAP diet beat other dietary interventions for IBS, review finds

A diet low in fermentable oligosaccharides, disaccharides, monosaccharides, and polyols (FODMAP) ranked first among treatments for abdominal pain severity and abdominal bloating or distension severity in irritable bowel syndrome (IBS), a recent study found.

Researchers reviewed 13 randomized controlled trials (RCTs) of 944 patients that evaluated a low FODMAP diet in IBS. Treatment efficacy was determined by improvement in global or individual IBS symptoms, including abdominal pain, abdominal bloating or distension, and bowel habit. The results of the systematic review and meta-analysis were published Aug. 10 by Gut.

On the outcome of achieving improvement in global IBS symptoms, a low FODMAP diet ranked first versus habitual diet (relative risk [RR] for no symptom improvement, 0.67; 95% CI, 0.48 to 0.91) and was superior to all other interventions. A low FODMAP diet also ranked first for abdominal pain severity, abdominal bloating or distension severity, and bowel habit. It was superior to British Dietetic Association (BDA)/National Institute for Health and Care Excellence (NICE) dietary advice for abdominal bloating or distension (RR, 0.72 [95% CI, 0.55 to 0.94]), which was not superior to any other intervention in any analysis. For bowel habit, a low FODMAP diet was not superior to any other intervention.

The researchers noted that most of the included trials involved a dietician-led intervention in secondary or tertiary care settings, did not study the effects of FODMAP reintroduction on symptoms, and inadequately reported adverse events. “Our results confirm that a low FODMAP diet is an efficacious treatment for global IBS symptoms in secondary and tertiary care,” the authors wrote. They called for additional RCTs in primary care that compare a low FODMAP diet and BDA/NICE dietary advice against each other or against sham dietary advice. Such trials, they wrote, should be “powered adequately, [use] FDA-recommended endpoints, examine efficacy during the FODMAP reintroduction and personalisation phase, and report adverse events data more thoroughly.”