Postbiotics in Respiratory Health: Functional Components, Innovative Application, and Emerging Challenges

Respiratory tract infections (RTIs) are typically self-limiting, yet the prevalence of irrational antibiotic prescriptions remains a significant concern, contributing to the growing issue of antibiotic resistance. Postbiotics, emerging as a promising strategy for the prevention and treatment of RTIs, represent a rapidly evolving field of research. This review provides an overview of the pathogenesis of RTIs, explores the functional components of postbiotics, and evaluates their potential applications in respiratory health. Key functional components, including cell-free supernatants, cell wall fragments, bacteriocins, and short-chain fatty acids, have demonstrated diverse health benefits, such as immune modulation, antioxidant properties, and anti-inflammatory effects. Animal studies revealed that postbiotics can prolong survival time and reduce lung viral titers in influenza-infected mice. Clinical trial outcomes were mixed but encouraging, with specific postbiotics showing efficacy in reducing RTI incidence and bolstering immune responses, particularly in vulnerable populations such as children and the elderly. A strengths, weaknesses, opportunities, and threats analysis concluded that postbiotics offer major advantages in terms of health benefits, stability, safety, and manufacturing flexibility. However, challenges related to standardization, regulatory hurdles, and the need for a deeper understanding of their mechanisms of action must be addressed to facilitate broader commercial applications.