November 26, 2022

New Review Investigates the Efficacy of an IBS Diet in the Treatment of SIBO

Irritable bowel syndrome (IBS) can be debilitating causing cramping, abdominal pain, bloating, gas, diarrhea and constipation. IBS can affect and one’s work, sleep and relationships.

Most treatments for IBS consist of medications that are often ineffective and can have numerous side effects.

According to a review published this month in Nutrients, researchers investigated the current recommendations regarding nutrition in IBS to determine if they are suitable for patients with small intestinal bacterial overgrowth (SIBO).

A narrative literature review was carried out using several databases. Recent studies have demonstrated that dietary manipulation may have a role in mitigating SIBO gastrointestinal symptoms. Interestingly, a low FODMAP diet proposed for IBS may promote a negative shift in the gut microbiome and exacerbate the existing dysbiosis in patients with SIBO.

On the other hand, supplementation with soluble fiber can lessen the symptoms in IBS and SIBO. In addition, specific probiotic supplementation may increase the efficacy of antibiotic treatment and regulate bowel movements. Optimal dietary patterns play a key role in the treatment of SIBO.

FODMAPs act as prebiotics and modulate the gut microbiome by stimulating the growth of beneficial bacteria and promoting the production of short-chain fatty acids, so a low-FODMAP diet might be characterized as anti-prebiotic because of its reduction in beneficial bacteria species.

Most studies compared a low-FODMAP diet in IBS patients to traditional dietary recommendations, habitual diets or a high-FODMAP diet. None of the studies investigated

the impact of this diet in SIBO patients.

The effect of single strain probiotic supplementation on the modification of gut microbiome

was assessed in 11 studies. Only one study included patients with SIBO. The results

demonstrated that supplementation with Saccharomyces boulardii was associated with a significantly higher eradication rate and a decline in exhaled hydrogen compared to metronidazole therapy. The nine remaining studies were carried out in patients with IBS,

constipation, and healthy individuals.

Dietary fiber should also be considered an essential nutrient for the growth of beneficial bacteria as a prebiotic. The included studies support that increasing the

intake of fiber, particularly, soluble fiber, shows beneficial results in patients with GI

symptoms and modulation of the gut microbiome, however, studies in SIBO patients are still needed.

The gastrointestinal tract is the body’s ‘second brain,’ it is made up of a self-contained, complex network of neurons, neurotransmitters, and proteins embedded in the lining of the GI system. It is responsible for all aspects of the digestive process, from the esophagus to the stomach and small and large intestines and may be responsible for IBS symptoms.

There are other nutrients that can support patient with IBS. For example. Perilla frutescens is an herb native to Eastern Asia that demonstrates antispasmodic, prokinetic, and anti-inflammatory effects, which help normalize and promote health bowel function and provide relief from GI symptoms.

By Michael Jurgelewicz, DC, DACBN, DCBCN, CNS

Source: Wielgosz-Grochowska J, Domanski N, et al. Efficacy of an Irritable Bowel Syndrome Diet in the Treatment of Small Intestinal Bacterial Overgrowth: A Narrative Review. Nutrients. 2022 Aug 17;14(16):3382.