Effects of galactooligosaccharides (GOS) on the gut microbiota in lactose intolerant individuals

Abstract

Lactose intolerance (LI), which affects approximately 75% of the global population, leads to symptoms such as abdominal pain, bloating and diarrhea. The primary management strategy for LI involves the avoidance of lactose-containing products. Although there is no cure for LI of genetic origin, the administration of prebiotics, including the consumption of galactooligosaccharides (GOS) and, potentially, the regular, low-level intake of lactose, may modify the gut microbiota to aid in symptom management. We conducted a six-week, single-blind trial on 14 participants who self-reported LI to examine the effects of GOS vs. low level lactose in the context of a normal diet on the gut microbiota. Fecal samples, gastrointestinal symptom reports and dairy consumption data were collected throughout the study. No significant changes in alpha and beta microbial diversity were observed within the GOS and lactose groups individually. There were significant increases in Actinobacteria ( P <0.0001) and Firmicutes ( P =0.0006) phyla in the GOS group. Additionally, a considerable elevation in amount of the genus Bifidobacteria ( P <0.0001) and a reduction in self-reported diarrhea incidents ( P =0.0085) were observed in the GOS group. The findings suggest that GOS enhances the presence of commensal Bifidobacteria and potentially alleviates LI symptoms. • Galactooligosaccharides (GOS) may alleviate the lactose intolerance symptoms. • GOS supplementation changed the microbiota in lactose intolerant humans. • Significant increases in Actinobacteria and Firmicutes phyla in the GOS group. • Considerable increase in the amount of genus Bifidobacteria in the GOS group. • GOS enhances the presence of Bifidobacteria and potentially reduces LI symptoms.