A Comparison of the In Vitro Effects of 2’Fucosyllactose and Lactose on the Composition and Activity of Gut Microbiota from Infants and Toddlers

Editor(s): Pieter Van den Abbeele , Norbert Sprenger , Jonas Ghyselinck , Benoît Marsaux , Massimo Marzorati , and Florence Rochat .

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Health benefits of breastfeeding and human milk are widely recognised. HMOs – bioactive components found in human milk – are known to support the growth and metabolic activity of the gut microbiota, and 2’-FL is generally the most abundant of these. Previous studies have shown that adding 2’-FL to infant formula milk, either alone or in combination with the HMO Lacto-N-neotetraose (LNnT), helps to support immune and gut health. However, little is known about the specific role that 2’-FL plays and its impact on toddler microbiota.

This study, funded and co-authored by Nestlé Research, used two in vitro models – 48-hour fecal incubations, and the long-term mucosal simulator of the human intestinal microbial ecosystem (M-SHIMEÒ) – with fecal samples from 3-month-old breastfed (BF) infants or toddlers aged 2-3 years.

2’-FL fermentation was shown to strongly and immediately increase the relative abundance of Bifidobacteriaceae in the gut microbiota of both babies and toddlers. By contrast, lactose fermentation had a less immediate bifidogenic effect of the toddler microbiota, and did not increase the prevalence of Bifidobacteriaceae in the infant microbiota during the first two treatment weeks. 2’-FL fermentation was also associated with consistently lower gas production than fermentation of lactose. This suggests that 2’-FL not only promotes the growth of beneficial bifidobacteria, but may also help reduce intestinal discomfort. The study’s authors further theorise that 2’-FL may plausibly help to maintain the presence and activity of bifidobacteria in the infant’s gut beyond six months of age, when weaning begins to diversify their microbiota.