Nasal breathing: a neglected factor in metabolic regulation?

[PURPOSE] Nasal breathing (NB) is a fundamental physiological process, and emerging research indicates its potential role in modulating resting metabolism, impacting energy expenditure and metabolic efficiency. This study investigates the impact of NB on resting metabolic rate (RMR), offering novel insights into metabolic regulation.

[METHODS] A prospective study was conducted on patients undergoing nasal surgery, with measurements taken before and 3 months after surgery. Metabolic rate assessments, anthropometric dimensions, and peak nasal inspiratory flow (PNIF) were recorded. Factors like age, sex, and health status were considered to control for confounding variables.

[RESULTS] A total of 83 patients were initially enrolled: 17 underwent septorhinoplasty (SRP), 61 septoplasty (ST) and 5 inferior turbinate reduction alone. 72 patients completed the follow-up. SRP patients exhibited significantly higher pre- and post-operative RMR compared to ST patients (p = 0.005), and this association was not observed when PNIF was included in the analysis (p > 0.05). Pre-operative and post-operative PNIF values significantly correlated with pre-operative and post-operative RMR (p = 0.049 and p = 0.005, respectively). Post-operative PNIF predicted post-operative RMR after confoundment adjustment in linear regression (β = - 0.043, p = 0.017). Importantly, total body weight increased after surgery (pre-op: 74 ± 14.6 kg versus post-op: 75.6 ± 15.5 kg, p < 0.001) due to an increment in muscle mass (pre-op: 52.3 ± 12 versus post-op: 55.5 ± 14, p < 0.01).

[CONCLUSION] Preliminary analysis suggests a potential link between NB and RMR, emphasizing the overlooked role of nasal respiratory physiology in energy homeostasis. Surgery also elicited body composition alterations. Further research is needed to uncover the underlying mechanisms of this association. Understanding the impact of NB on RMR could underscore its significance in metabolic regulation, reinforcing the importance of nasal surgery on overall health. This study provides foundation for future investigations.