The gut microbiome significantly influences human health with dietary patterns, a key factor that modulates the structure and function of microbiome consortia. Plant-based diets (PBDs), including vegan and vegetarian, are linked to positive alterations in gut microbiota by stimulating the bacterial growth necessary for producing short-chain fatty acids (SCFAs). These microbial alterations help reduce inflammation, enhance gut barrier integrity, and improve metabolic health. However, not all PBDs offer beneficial effects. Recent findings highlighted that raw or minimally processed foods may transmit plant and soil-derived microbes, such as Enterobacter hormaechei, Citrobacter freundii, Raoultella ornithinolytica, and Klebsiella pneumonia into the human gut, raising concern about opportunistic infections. Although PBDs benefit in lowering the risk of chronic diseases such as obesity, diabetes, and inflammatory bowel disease, proper dietary planning is necessary to prevent potential nutrient deficiencies. Upcoming research should explore personalized nutrition, long-term microbiome shifts, and microbial transplants to improve gut health through PBDs.
Keywords: PBDs; SCFAs; gut microbiome; vegan; vegetarian.
Copyright © 2025 American Society for Nutrition. Published by Elsevier Inc. All rights reserved.