The adoption of a westernized gut microbiome in Indian Immigrants and Indo-Canadians is associated with dietary acculturation

Abstract

Indian immigration to westernized countries has recently surged, increasing their risk of Inflammatory Bowel Disease (IBD) post-migration. While crucial for understanding IBD risk, the gut microbiome remains understudied in Indians. This cross-sectional study examines the gut microbiomes of Indians residing in India, Indo-Immigrants, and Indo-Canadians in comparison to Euro-Canadian and Euro-Immigrant controls to understand the impact of westernization on their gut. Stool samples for 16S rRNA and shotgun sequencing assessed microbial taxa and functional profiles, complemented by dietary and demographic data to evaluate lifestyle patterns. Results revealed distinct microbiotas in Indians and Indo-Immigrants compared to control groups, with high abundances of Prevotella spp. and CAZymes reflecting their high complex carbohydrate diet. Indo-Canadians exhibited a transitional microbiome towards westernization, mirroring increasing dietary acculturation. Considering 44% of Canadians are first- and second-generation immigrants and the global adoption of westernized practices, future research should investigate the health implications of such microbiome transitions in immigrant populations and newly industrialized nations.