Researchers analyzed genetic and questionnaire data from 268,606 people of European and East Asian descent and identified 21 regions of the genome affecting bowel movement frequency, 10 of which were previously unknown.[1][2][3] The study confirmed known gut pathways, such as gastric acid regulation and nerve signaling, and revealed a new link with vitamin B1 (thiamine).[2][3][4] The most prominent gene signal concerned the genes SLC35F3 and XPR1, which are involved in the transport and activation of thiamine in the body.[2][3][5] In an analysis of dietary data from 98,449 UK Biobank participants, higher dietary thiamine intake was associated with more frequent bowel movements.[1][2][3] This association depended on the genetic profile in the SLC35F3 and XPR1 genes, assessed as a combined genetic score.[2][3][5] Findings suggest a biological link between bowel movement frequency and irritable bowel syndrome (IBS).[2][3][4] The study provides the basis for further research, including laboratory experiments and clinical trials focused on vitamin B1.[3][4][7]