Role of the gut microbiome in mediating lactose intolerance symptoms

Correspondence to Dr Alexander Kurilshikov, Department of Genetics, University Medical Centre Groningen, Groningen 30001, 9700, The Netherlands; a.m.kurilshchikov@umcg.nl Misselwitz et al recently reviewed the multifactorial aspects of lactose intolerance (LI).1 Their work highlights the known effects of genetic makeup and dietary patterns in the occurrence of gastrointestinal symptoms in LI individuals. The authors define LI as the occurrence of gastrointestinal complaints on lactose exposure and discuss the wide variety of symptoms among LI patients.1 Regarding lactose metabolism, Misselwitz et al mention the influence of the gut microbiome, in particular that Bifidobacterium or other lactose-fermenting bacteria are reported to affect the levels of lactose in the gut. [...]gut complaints were assessed via a 7-day questionnaire where participants were asked to rank (from 1 to 5) their daily level of gastrointestinal discomfort in six categories: ‘abdominal discomfort’, ‘bloating’, ‘burping’, ‘abdominal pain’, ‘flatulence’ and ‘nausea’.