The Impact of Smoking on Microbiota: A Narrative Review

Abstract

Cigarette smoke is a classic risk factor for many diseases. The microbiota has been recently indicated as a new, major player in human health. Its deregulation—dysbiosis—is considered a new risk factor for several illnesses. Some studies highlight a cross-interaction between these two risk factors—smoke and dysbiosis—that may explain the pathogenesis of some diseases. We searched the keywords “smoking OR smoke AND microbiota” in the title of articles on PubMed®, UptoDate®, and Cochrane®. We included articles published in English over the last 25 years. We collected approximately 70 articles, grouped into four topics: oral cavity, airways, gut, and other organs. Smoke may impair microbiota homeostasis through the same harmful mechanisms exerted on the host cells. Surprisingly, dysbiosis and its consequences affect not only those organs that are in direct contact with the smoke, such as the oral cavity or the airways, but also involve distant organs, such as the gut, heart, vessels, and genitourinary tract. These observations yield a deeper insight into the mechanisms implicated in the pathogenesis of smoke-related diseases, suggesting a role of dysbiosis. We speculate that modulation of the microbiota may help prevent and treat some of these illnesses.

Influence of perinatal and childhood exposure to tobacco and mercury in children’s gut microbiota

“…Bacteriodes vulgatus, Eubacterium rectale), but these results were not found in our study (Shen et al, 2022). Cigarette smoking has been consistently linked to alterations in the gut microbiome among adults (Cicchinelli et al, 2023). The impact of maternal smoking during gestation on the prenatal and perinatal gut environment is also suspected.…”

Coffee and Microbiota: A Narrative Review

“…It is now well known how lifestyle (e.g., smoking) affects the composition of the gut microbiota [64], and again one of the reasons we have devoted ourselves to this topic is precisely to thoroughly investigate this habit, which is as widespread in the world as coffee drinking.…”

Environmental exposures, the oral–lung axis and respiratory health: The airway microbiome goes on stage for the personalized management of human lung function

“…The airway microbiome is constantly affected by numerous factors that challenge the respiratory health including host genetics, diet, alcohol, physical activity, drugs, exposure to toxicants such as smoke, biofuel and pollutants and oral health (Cicchinelli et al., 2023; Du et al., 2023; Lim et al., 2016; Xue et al., 2020). Here, we focus on cigarette smoking and oral health, which are closely related to each other and to COPD risk, development and progression.…”

“…Cigarette smoking influences the composition of the airway microbiota due to, among others, exposure to bacterial pathogens contained in the cigarettes themselves; impaired antimicrobial defences due to the immunosuppresive nature of tobacco; physiological changes in the airway microenvironment that facilitate the outgrowth of anaerobes through reduced oxygen, acid production and pH shift (Huang & Shi, 2019). Smoking is also a major environmental factor influencing the composition of the oral and subgingival microbiota, and smokers have oral dysbiosis with a highly diverse, pathogen‐rich, commensal‐poor and anaerobic oral microbiome (Cicchinelli et al., 2023; Huang & Shi, 2019). Smoking effects on the oral microbiome have an impact on the lower airway dysbiosis through the oral–lung axis and, therefore, on respiratory health.…”