One of the most common issues that I’m contacted for is IBS. IBS (irritable bowel syndrome) affects roughly 5 to 10% of people worldwide, though people may have it and not be diagnosed. Women are more commonly diagnosed with IBS, but men may suffer from it, too.

Brain-Gut Axis

The brain-gut axis is the connection between our brain and our gut. The hippocampus and amygdala are areas of the brain that regulate depression and anxiety. Scientists believe there’s a link between psychological health and gut microflora (bacteria in the bowel).

Bacteria can start inflammatory reactions in the bowel. In addition, our microflora is involved in metabolizing serotonin, a neurotransmitter needed to keep our brains calm. Anxiety and depression are both linked with IBS.

When under stress, your gut may react causing you to experience more gas, bloating, diarrhea, or other unpleasant issues.

Reducing stress certainly helps and what you put on your plate can be equally important. New research suggests that diet is more effective than medication.

Research on IBS

Research conducted at the University of Gothenburg indicates that dietary modifications improved symptoms in over seven out of ten patients compared to medication.

As mentioned above, Irritable bowel syndrome (IBS) is a common condition that causes abdominal pain, gas, bloating, diarrhea, and, or constipation, in various combinations and with different degrees of severity.

Patients with IBS are often told to eat small, frequent meals and reduce intake of trigger foods including alcohol, coffee, and carbonated drinks. Medications that reduce gas, bloating, and abdominal pain may be prescribed in addition to those that treat constipation. Antidepressants may also be used to improve IBS symptoms.

The recent study was published in The Lancet Gastroenterology & Hepatology. It compared three treatments: two dietary and one based on the use of medications. Subjects in the study were adults with severe or moderate IBS symptoms at Sahlgrenska University Hospital in Gothenburg.

Symptom Relief Following Diet Modifications

Subjects were divided into 3 groups of 100 subjects. The first group was advised to follow a low FODMAP diet. FODMAPS are fermentable carbohydrates that may increase gas production in the gut. These include foods containing lactose, gluten, beans, onions, and other fruits and vegetables that may cause pain in IBS.

The second group of subjects were given a diet that was high in protein and fat and lower in carbohydrates. The final group was given traditional medication used for IBS.

The treatment periods for each group lasted four weeks. After the researchers reviewed how well the subjects responded to each treatment, one treatment stood out.

In those who received dietary advice and low content of FODMAPs, 76% had significantly reduced IBS symptoms. In the second group who were advised on low carbohydrates and high protein and fat, the proportion was 71%, and 58% improved in the medication group.

Quality of life, reduced IBS symptoms and reduced anxiety and depression were observed in all three groups.

Personalization Matters

After 6 months when subjects in the diet groups returned to their previous eating routines, 68% in the low FODMAPs group still had reduced IBS symptoms, while 60% in the low carbohydrate group had fewer symptoms.

Sanna Nybacka, Researcher and Dietitian, led the study in addition to Stine Störsrud, Associate Professor, and Magnus Simrén, Professor and Senior Consultant, all at Sahlgrenska Academy, University of Gothenburg.

Nybacka notes, "With this study, we can show that diet plays a central role in the treatment of IBS, but that there are several alternative treatments that are effective.”

More information is needed to personalize IBS treatment in the future and more studies by her group will be conducted.

Final Thoughts

A low FODMAPS diet is an elimination diet and is not meant to be followed forever. Most individuals with IBS remove foods high in FODMAPs from their diet and gradually add them back in to see which ones trigger symptoms.

If you have IBS, you can keep a food and symptom diary to monitor if certain foods aggravate your symptoms. Some of the biggest offenders are alcohol, caffeine, and fizzy drinks.

In addition, gassy vegetables (broccoli, cabbage, cauliflower, kale), beans and lentils, garlic, onions, and certain fruits such as apples and mangoes may impact IBS.

Dairy products including milk, ice cream, and yogurt may also flare up IBS symptoms.

Foods that are naturally low in FODMAPSs include carrots, green beans, zucchini, bell peppers, and potatoes. Oatmeal, rice, and other gluten-free grains appear safe as well. Fruits including bananas, berries, cherries, grapes, and melon appear well tolerated.

Work with a dietitian to personalize your diet.

Journal Reference:

1. Sanna Nybacka, Hans Törnblom, Axel Josefsson, Johann P Hreinsson, Lena Böhn, Åsa Frändemark, Cecilia Weznaver, Stine Störsrud, Magnus Simrén. A low FODMAP diet plus traditional dietary advice versus a low-carbohydrate diet versus pharmacological treatment in irritable bowel syndrome (CARBIS): a single-centre, single-blind, randomised controlled trial. The Lancet Gastroenterology & Hepatology, 2024; DOI: 10.1016/S2468-1253(24)00045-1