To Low FODMAP or Not to Low FODMAP, That is the Question

Do you suffer from small intestinal bacterial overgrowth, commonly called SIBO? The symptoms aren’t fun.

Here are a few of them:

• Gas and/or bloating
• Diarrhea and/or constipation
• Food intolerances
• Weight gain or loss
• Chronic body discomfort

If you’ve been diagnosed, you might have been instructed to follow a low-FODMAP diet. It’s a strategy often recommended by integrative practitioners.

For a deeper understanding of SIBO, check out this blog post.  

Low-FODMAP Diet: Not as Fun as Its Name

FODMAP is an acronym for Fermentable Oligosaccharides, Disaccharides, Monosaccharides, and Polyols. (That’s a mouthful!). Foods that fall into this category include, but are not limited to, garlic, onion, soybeans, bananas (ripe), avocados, mango, nectarines, almond flour, cashews, agave, and honey. The low-FODMAP diet is highly restrictive and eliminates these and other foods that are thought to cause intestinal distress. 

So what’s the issue? The phytonutrients in these foods feed bacteria in the gut – which is a problem when they grow in the small intestine, as in SIBO (instead of in the large intestine where they belong). 

But it turns out we need those phytonutrients and the bacteria they support. Taking all these foods out long term may cause deficiencies and throw off the balance of the microbiome (microorganisms) in the gut. Not to mention, most people find these dramatic food restrictions to be unsustainable.

Common Approaches to Dealing with SIBO Symptoms

Conventional treatment is usually one round – or more – of antibiotics, but the problem often resurfaces.

The low-FODMAP diet has been widely adopted as an alternative way to combat ever-present SIBO symptoms. It is considered an optimal nutritional management approach for IBS, which approximately 70% of SIBO patients may have. So it makes sense that this dietary intervention might support them. New research shows that may not be the case.

The Latest on Low-FODMAP Diet & SIBO

A recent article in the journal Nutrients reviewed 34 published studies, 12 of which evaluated a low-FODMAP diet and microbial health.

When taken as a whole, these studies suggested that 4–9-weeks of a low-FODMAP diet may adversely affect the gut microbiome, specifically resulting in a decrease in beneficial bacteria, some of which influence gut health and are even involved in immune system function, metabolism, and brain health! 

And if that wasn’t cause enough for concern, researchers also found the following outcomes: 

• A low-FODMAP diet may cause progression toward hydrogen sulfide SIBO
• Keystone bacterial species were negatively affected
• Dysbiosis (imbalance between beneficial and harmful organisms) got worse – which is a possible underlying cause of SIBO in the first place!

While attempting a low-FODMAP diet may provide short-term relief of symptoms, maintaining this diet for the long term may be detrimental to the health of the gut microbiome and, ultimately, the human host. 

Botanicals Studied as an Alternative Approach

On an optimistic note, there are other therapeutic approaches. Botanicals offer a time-tested alternative for natural microbiome support and are less disruptive to the microbiome than conventionally used therapies. 

Herbs tested for their beneficial effects regarding SIBO include oil of oregano, berberine, wormwood, lemon balm, red thyme, Indian barberry, garlic, black cumin, cloves, cinnamon, thyme, all-spices, bay leaves, mustard, peppermint, and rosemary. 

If you are dealing with SIBO, discuss researched botanical formulations with your practitioner. Botanical blends, in particular, have proven to be helpful in restoring microbial balance to the gut and resolving SIBO.

1. Wielgosz-Grochowska JP, Domanski N, Drywień ME. 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. doi: 10.3390/nu14163382. PMID: 36014888; PMCID: PMC9412469.
2. Binda, C., Lopetuso, L. R., Rizzatti, G., Gibiino, G., Cennamo, V., & Gasbarrini, A. (2018). Actinobacteria: A relevant minority for the maintenance of gut homeostasis. Digestive and Liver Disease, 50(5), 421–428.