How HMOs Support Gut Health and Improve Irritable Bowel Syndrome Symptoms

January 13, 2021 4 min read

How HMOs Support Gut Health and Improve Irritable Bowel Syndrome Symptoms - Layer Origin Nutrition

Irritable Bowel Syndrome (IBS)

Most people have heard of irritable bowel syndrome or the possibly better known acronym for it, which is IBS.Most people would also probably struggle to define IBS or explain what it actually is or is not. Yet, if I were to ask whether you've had any constipation, diarrhea, abdominal pain, or gas, most of people would say yes. 

IBS is a chronic disorder that affects the large intestine. Signs and symptoms include cramping, abdominal pain, bloating, gas, plus diarrhea and/or constipation. IBS is one of the most common disorders of the digestive tract with a prevalence of 12% among the general population.1IBS isn’t life-threatening but it can be a long-lasting problem that changes how you live your life. 

Blue doctor's folder that says Irritable Bowel Syndrome

Surprisingly, IBS reduces health-related quality of life to a greater degree than either diabetes mellitus or end-stage renal disease. In other words, it's really bad. 

IBS and gut microbiota

Although there have been many studies attempting to explore the pathophysiology of IBS, the disease is still not clearly understood. The human gut is a complex structure and is inhabited by trillions of microorganisms including bacteria, fungi, viruses, eukaryotes, and archae. How people get IBS is unknown, but the gut microbiota is an increasingly recognized factor in the pathogenesis of IBS. This is evident from the fact that IBS occurs more frequently after intestinal infection or antibiotic treatment. 

Anti-biotic pills spilling out from a bottle onto a blue table

 So, we don't know what causes it, but we know it involves the gut. 

In fact, studies have shown that change of both composition and quantity of the intestinal microbiota are observed in IBS patients.2 The change in gut microbiota may further contribute to low-grade inflammatory responses related to IBS.

[RELATED POST: Where can you get HMOs for adults? (Human Milk Oligosaccharides)]

The role of the gut microbiota in the development and treatment of IBS centers on the change in the metabolites produced by gut microbiota. These metabolites are key nutrients for gut barrier function. The beneficial bacteria (probiotics) may influence intestinal luminal environment, help to maintain epithelial and mucosal barrier function and modulate mucosal or systemic immune system.2,3

Did you get all that?

Basically, we have evidence indicating that you can influence IBS symptoms by regulating the bacteria in your gut. 

Post It notes with one letter on each spelling IBSThere are a growing number of studies supporting the roles of probiotics in the pathogenesis of IBS. Since diet is one of the main contributors to the composition of the human gut microbiota, dietary interventions are increasingly used in treating IBS.

Human milk oligosaccharides (HMO) serve as prebiotics supporting gut health and improving IBS symptoms

Bifidobacteria is one of the most important probiotics for infants to prevent infection and produce vitamins and other important chemicals. The gut microbiome of breastfed infants is typically dominated by bifidobacterial species, particularly by Bifidobacterium Infantis. Research has shown that the gut microbiota of patients with irritable bowel syndrome (IBS) lack a healthy abundance of bifidobacteria. 

You might be wondering: "So how can I get some?" 

Supplementation with bifidobacteria has been shown to have a beneficial impact on IBS symptoms.4 However, as supplementation with probiotics introduces a single or few bacterial strains, potentially foreign to the gut, supplementation with prebiotics such as HMO, supports the growth of beneficial bacteria already present in the gut. 

As HMOs are largely indigestible in the upper gastrointestinal (GI) tract, the majority of HMOs reach the large intestine undigested. HMOs function as the foods for the beneficial bacteria. Without the foods, probiotics can hardly grow and thrive. Supplementation with HMOs has previously been shown to increase the abundance of bifidobacteria, in healthy infants, children, healthy adults, and in adults with IBS.5,6

Graphic of Pac-Man and food representing probiotics and probiotics.

Based on a study in patients with IBS, two types of HMOs (2'-fucosyllactose (2'FL) and lacto-N-neotetraose (LNnT)) could support normal bowel function in adults suffering from IBS without causing tolerance or safety issues.6 They may also, through modulation of intestinal microbiota and associated metabolites, improve general gut health resulting in better management of IBS-related symptoms and overall wellbeing. For anyone who knows the struggle of dealing with IBS day in and day out, this is big. Any chance for consistent relief is welcomed with opens arms. 

Another recent clinical study showed daily ingestion of a 5 gram mix of 2'FL and LNnT (in a 4:1 mass ratio) reduced abnormal stool consistency, improved abdominal pain, bloating, and overall IBS severity, and increased IBS-related quality of life. 7

HMOs support gut health and improve symptoms of IBS in multiple ways. 7,8

  • HMOs serve as prebiotics to promote the growth of beneficial bacteria.
  • HMOs provide beneficial bacteria with a growth advantage compared with potential pathogens.
  • HMOs modulate host-epithelial immune responses and prevent the binding of pathogenic bacteria and viruses to the gut.

There is a growing acceptance in the medical community for recommending microbiota-directed therapies. Serving as prebiotics, HMOs have shown huge benefits for gut health and can be used as a promising candidate to improve symptoms of IBS.

Rainbow hued see-through human body showing gut Human Milk Oligosaccharides are certainly worth considering if you whether you have been diagnosed with IBS or even if you have not been diagnosed but are experiencing severe symptoms. 


  1. Lovell, Rebecca M., and Alexander C. Ford. "Global prevalence of and risk factors for irritable bowel syndrome: a meta-analysis." Clinical gastroenterology and hepatology 10.7 (2012): 712-721.
  2. Lee, Beom Jae, and Young-Tae Bak. "Irritable bowel syndrome, gut microbiota and probiotics." Journal of neurogastroenterology and motility 17.3 (2011): 252.
  3. Ng, S. C., et al. "Mechanisms of action of probiotics: recent advances." Inflammatory bowel diseases 15.2 (2009): 300-310.
  4. Staudacher, Heidi M., and Kevin Whelan. "Altered gastrointestinal microbiota in irritable bowel syndrome and its modification by diet: probiotics, prebiotics and the low FODMAP diet." Proceedings of the Nutrition Society 75.3 (2016): 306-318.
  5. Elison, Emma, et al. "Oral supplementation of healthy adults with 2′-O-fucosyllactose and lacto-N-neotetraose is well tolerated and shifts the intestinal microbiota." British Journal of Nutrition 116.8 (2016): 1356-1368.
  6. Iribarren, Cristina, et al. "Human milk oligosaccharide supplementation in irritable bowel syndrome patients: A parallel, randomized, double‐blind, placebo‐controlled study." Neurogastroenterology & Motility 32.10 (2020): e13920.
  7. Palsson, Olafur S., et al. "Human Milk Oligosaccharides Support Normal Bowel Function and Improve Symptoms of Irritable Bowel Syndrome: A Multicenter, Open-Label Trial." Clinical and Translational Gastroenterology 11.12 (2020).
  8. Bode, Lars. "Human milk oligosaccharides: every baby needs a sugar mama." Glycobiology 22.9 (2012): 1147-1162.



Leave a comment


The Human Milk Oligosaccharide - 2'-Fucosyllactose (2'-FL) Prevents Intestinal Inflammation Cover Image
The Human Milk Oligosaccharide - 2'-Fucosyllactose (2'-FL) Prevents Intestinal Inflammation, Study Finds

July 12, 2024 6 min read

Human milk oligosaccharides (HMOs), particularly the glycan known as 2’-Fucosyllactose (2’-FL), have been a cornerstone in neonatal nutrition, offering the first sweet taste and vital energy while establishing a thriving gut microbiome. Recent studies have expanded the understanding of these substances, with research showing 2’-FL's pivotal role in not only fostering beneficial gut bacteria but also in potentially mitigating adult conditions such as colitis. The Schalich et al. (2024) study further explores this by investigating 2’-FL's ability to modulate gut microbial metabolism, suggesting a promising future for HMOs in adult disease prevention and therapy, particularly for inflammatory bowel diseases like colitis.
Read More
How Akkermansia Survives and Thrives in the Gut?
How Akkermansia Survives and Thrives in the Gut?

June 27, 2024 6 min read

Discover some of the unique mechanisms Akkermansia employs to survive in the human gut and the genetics behind how this fascinating bacterium can maintain cholesterol homeostasis.
Read More
Study Finds Short-Term Cranberry Supplementation Has A Strong Bifidogenic Effect In The Human Gut - Blog Layer Origin
Study Finds Short-Term Cranberry Supplementation Has A Strong Bifidogenic Effect In The Human Gut

June 21, 2024 7 min read

Understand how cranberry extracts could improve the composition of the gut microbiome, increasing the abundance and activities of friendly bacteria and potentially offering a solution to combat the effects of the Western diet.
Read More