Human Milk Oligosaccharides

From the breast of the mother, human milk oligosaccharidea (HMOs) are the third most abundant component in breast milk and are responsible for the growth of Bidfidobacteria. Ultimately HMOs increase short chain fatty acids, particularly butyrate. Butyrate is the preferred fuel for cells lining the colon and helps maintain gut barrier and immune status.

Butyrate is the preferred fuel for cells lining the colon and helps maintain gut barrier and immune status

Insufficiency of butyrate is linked to obesity which is a risk factor for other metabolic diseases such as type 2 diabetes, cardiovascular diseases, dyslipidemia, non-alcoholic fatty liver disease, chronic kidney disease, obstructive sleep apnea and hypoventilation syndrome, mood disorders and physical disabilities. Butyrate production naturally occurs with the consumption of resistant starches such as cooked and cooled potatoes, raw bananas, legumes, plant material and partly milled seeds. It also naturally occurs in milk products as a result of the fermentation in the cow’s gut and human milk, as delivered to a breast feeding infant.

HMOs, specifically 2′-Fucosyllactose (2′-FL), serve not only as a prebiotic, but also provide pathogen blocking immune benefits (reduced respiratory, urinary tract and gastrointestinal infections), support brain development and enhanced cognitive function, and if not naturally from breast milk, improves formula tolerance.

Bifido bacteria (Bifidobacterium infantis, B. breve and B. bifidum) forms up to 90% of the colonic microbiome of vaginally born infants and decreases to 5% in adults. This continues to decline with age. Important for health, low levels of butyrate are linked to inflammatory bowel conditions, abdominal pain, discomfort, antibiotic associated diarrhea, obesity, allergies, and poor bowel function and autoimmune diseases.

Will adults benefit from HMO’s as infants do?

When a woman breast feeds, the amount of HMO that is transferred to the child depends on her FUT2 and FUT3 – fucosyltransferase – genetic status. Evidently, even those who are breastfed may still receive inadequate amounts of HMOs for populating beneficial levels of Bifidobacteria, affecting the level of butyrate production.  It helps to check not only your mother’s but your own status of FUT genes to understand your potential HMO needs more. More on this here.

HMO’s are different than other prebiotic oligosaccharides such as galacto-oligosaccharide (GOS), fructo-oligosaccharides (FOS), and xylo-oligosaccharides (XOS).  FOS, GOS and XOS can sometimes make gastrointestinal symptoms worse. HMOs are apparently more gentle and actually help gas, pain, bloat and bowel irregularities. Some even report HMO’s can be foundational in healthy weight management control.

HMOs are apparently more gentle and actually help gas, pain, bloat and bowel irregularities.

Since inflammatory bowel disease and obese patients generally have lower butyrate-producing bacteria and butyrate content, finding ways to help promote the Bifidobacterium which produces butyrate production is important. Regardless of whether the problems originate in early years from a non-vaginal birth, lack of breastfeeding, poor FUT2 genetic status of the breastfeeding mother, or in later years a disturbed microbiome status due to infection, stress or a poor diet, supplementing adults with tolerable resistant food based starch or human identical milk oligosaccharides may help provide relief.


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