Hearing impairment ranks as the third largest contributor to global disability among sensory disorders, with prevalence rising across younger and middle-aged populations alongside older adults. While prior research has linked certain lifestyle habits to hearing impairment risk, the underlying biological mechanisms have remained poorly understood. In particular, the relative contributions of systemic inflammation and metabolic dysregulation as intermediate pathways have never been systematically quantified, hindering the development of targeted preventive strategies for auditory health.
To address this gap, the Fudan University team conducted an analysis of 441,844 UK Biobank participants aged 40 to 69 at baseline, with a median follow-up of 14.22 years. The researchers constructed a comprehensive lifestyle score spanning seven behaviors: smoking status, alcohol consumption, physical activity, sleep duration, sedentary time, social engagement, and dietary supplement use. Over the study period, 20,743 incident cases of hearing impairment were documented. After full adjustment for demographics, medical history, ototoxic drug use, and noise exposure, participants with an ideal lifestyle had a 14% lower risk of developing hearing impairment than those with a poor lifestyle. Among individual factors, smoking cessation offered the greatest preventive benefit, followed by reduced sedentary time; dietary supplement use showed no protective effect, and social contact frequency was not significantly associated with hearing risk.
The study’s core insight emerges from its quantitative mediation analysis, which revealed metabolic dysfunction as the dominant biological pathway linking lifestyle to auditory health. Metabolic biomarkers—most notably BMI and HDL-c—mediated approximately 16.5% and 14.0% of the total lifestyle–hearing association respectively. In contrast, each inflammatory marker contributed less than 6% of the effect, playing only a secondary role. Further breakdowns showed distinct pathway patterns across behaviors: smoking exerts its harm through a roughly balanced combination of inflammatory and metabolic disruption, while the benefits of physical activity, reduced sitting time, and healthy sleep are driven primarily by metabolic improvements such as better insulin sensitivity, healthier lipid profiles, and lower adiposity. These metabolic changes are thought to preserve cochlear microcirculation and reduce oxidative damage to auditory hair cells.
The large sample size, long prospective follow-up, and consistent results across multiple sensitivity analyses strengthen the robustness of the findings. The authors acknowledge several limitations, as an observational cohort study, it cannot establish definitive causal relationships, and hearing impairment was defined using clinical diagnostic codes rather than objective audiometric measurements, which may introduce some misclassification. Additionally, the primary mediation analysis used baseline biomarker levels, though repeat measurement sensitivity analyses yielded largely consistent results.
The findings carry clear implications for public health and clinical practice, suggesting that hearing preservation strategies should extend beyond noise protection to include metabolic health management. “Hearing health is deeply intertwined with overall metabolic wellness,” the research team noted. “Prioritizing smoking cessation, reducing sedentary behavior, and maintaining healthy weight and cholesterol levels are actionable steps that may lower long-term hearing impairment risk.” Looking ahead, the team calls for further studies to validate these causal pathways and explore their relevance to specific hearing phenotypes, such as frequency-specific audiometric changes.

The work titled “Mediation Pathways from Lifestyle to Hearing Impairment: The Role of Inflammatory and Metabolic Biomarkers in a Prospective Cohort Study”, was published on ENT Discovery (published on May 27, 2026).
DOI：10.15302/ENTD.2026.060001