A recent review published in the journal Nutrients has examined the effectiveness and practical use of different dietary interventions for Irritable Bowel Syndrome (IBS). IBS affects an estimated 10-15% of adults worldwide and is characterized by abdominal pain, bloating, and changes in bowel habits that can impact daily life. Dietary management is a key approach to controlling symptoms, but with many diets being promoted, there is confusion about which ones are most effective and safe.
Traditional dietary advice remains the most widely recommended first-line treatment in Europe. This approach focuses on structured eating habits such as regular meals, avoiding skipping food, reducing fatty and spicy foods, limiting caffeine and alcohol, staying hydrated, and adjusting fiber intake towards more soluble fibers. Nearly half of patients experience symptom relief with this method according to clinical trials. However, the quality of evidence is considered low and results can vary depending on how well recommendations are followed.
The Low-FODMAP Diet (LFD) is one of the most researched diets for IBS. FODMAPs are short-chain carbohydrates that can cause gas and discomfort when not properly absorbed. The LFD involves three phases: restriction for 4-6 weeks, reintroduction of certain foods, and personalization based on individual tolerance. Randomized trials have shown that between 55% to 76% of participants achieve significant improvement in symptoms using this diet. Some studies also show benefits over certain medications like Otilonium Bromide. In North America, guidelines often suggest LFD as a first-line option; European guidelines typically recommend it after traditional advice.
Some research suggests improvements in anxiety and depression among those following LFD, though psychological outcomes are not always measured across studies. There are concerns about long-term effects on gut bacteria and nutrient deficiencies if the diet is not managed by a professional. "Without a dietitian's oversight, nutrient deficiencies, such as calcium and iron, can develop," notes the review's authors.
Many people try a gluten-free diet (GFD) even without having celiac disease because wheat contains both gluten and fermentable carbohydrates that may worsen symptoms. Trials show mixed results; some individuals report less diarrhea or lower symptom scores on GFDs—especially those with diarrhea-predominant IBS—but double-blind tests often do not confirm gluten as the main problem ingredient. GFDs may be socially restrictive or costly over time and could lead to insufficient intake of important nutrients.
The Mediterranean Diet (MD), which emphasizes fruits, vegetables, whole grains, olive oil, fish, and moderate dairy intake rather than elimination of foods, may help reduce IBS symptoms according to early studies. It may also support psychological well-being compared to habitual diets but includes some high-FODMAP foods that might trigger symptoms in sensitive people.
For patients with certain genetic variants affecting digestion—such as hypomorphic sucrase-isomaltase gene variants—a starch- and sucrose-reduced diet shows promise in reducing gastrointestinal symptoms along with fatigue or headaches; however these findings come from relatively short-term studies.
Other approaches like low-lactose or fructose-reduced diets generally only benefit those confirmed to have specific intolerances through testing.
Importantly,"overly restrictive eating may increase the risk of ARFID [Avoidant/Restrictive Food Intake Disorder], especially in individuals with multiple DGBIs." The review stresses personalized guidance: "Personalized guidance is essential to balance symptom control with nutritional adequacy."
Overall,"This review demonstrates that dietary therapy plays a central role in IBS management." The authors state: "The LFD has the strongest evidence for short-term symptom reduction while Traditional Dietary Advice remains a safe first-line option... no single diet fits all patients." They conclude that working closely with a registered dietitian who considers each patient's unique situation leads to better outcomes.
