Smoking and Obesity: A Microbial Perspective on Oral and Gut Microbiome Alterations

Hassan, Esraa Koriem; Abdalla, Salah; Abdellah, Ali; Azab, Marwa; Ramadan, Mohammed; Adel Ibrahim, Kareem

doi:10.21608/erurj.2025.292160.1152

Smoking and Obesity: A Microbial Perspective on Oral and Gut Microbiome Alterations

Document Type : Review article

Authors

¹ Microbiology and Immunology Department, Egyptian-Russian University, Badr City, Egypt

² Department of Microbiology and Immunology, Faculty of Pharmacy, Suez Canal University, Ismailia, Egypt.

³ Department of Microbiology and Immunology, Faculty of Pharmacy, Al-Azhar University, Assiut, Egypt

⁴ Department of Microbiology and Immunology, Faculty of Pharmacy, Egyptian Russian University

10.21608/erurj.2025.292160.1152

Abstract

The oral and gut microbiomes play crucial roles in human health and disease. Oral microbiome aids in digestion of food, provides colonization resistance against pathogens, modulates local and systemic inflammatory responses, and contributes to immune education. Contrastingly, the vast gut microbiome, comprising trillions of microbes inhabiting the gastrointestinal tract, is essential to nutrient absorption, vitamin synthesis, xenobiotic metabolism, and immune maturation. While maintaining the delicate balance and diversity within these microbial ecosystems is crucial for preserving physiological homeostasis, both smoking and obesity can mess up such equilibrium. Smoking and obesity are two major public health concerns that have been extensively studied for their detrimental impacts on human health. However, only few researches have shed light on the intricate interplay between these conditions and the microbial communities residing in the oral cavity and gut. Emerging cutting-edge molecular biology techniques such as 16S rRNA gene sequencing and next-generation sequencing have enabled high-resolution profiling of these complex microbial ecosystems. This review article delves into the significant alterations observed in the oral and gut microbiomes associated with smoking and obesity, shedding more light into the pivotal connection between these seemingly distinct habitats.

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