Background/Objectives: Elevated body temperature is a well-established biomarker of infection, increased disease risk, and adverse health outcomes. However, the relationship between resting body temperature and long-term survival in older individuals is complex. Emerging evidence suggests that higher basal body temperature is associated with reduced survival and accelerated aging in non-obese older adults. This study aimed to compare body temperatures across different age groups in hospitalized older adults. Methods: Data were retrospectively collected from 367 physically healthy residents of a mental health center. Longitudinal data from 142 individuals (68 men and 74 women), aged 45 to 70 years and monitored continuously over 25 years, were compared with cross-sectional data from 225 individuals (113 men and 112 women) who underwent periodic clinical examinations with temperature measurements. The cross-sectional sample was stratified into four survival categories. Resting oral temperatures were measured under clinical conditions to ensure protocol consistency. Age-related changes in both sexes were evaluated using standard regression analysis, Student's t-tests, ANOVA, and Generalized Linear Models. Results: Longitudinal analysis revealed an increase in body temperature with age among women, while cross-sectional analysis showed that long-lived residents generally had lower body temperatures compared to their shorter-lived counterparts. Conclusions: These findings support the hypothesis that lower lifetime steady-state body temperature is associated with greater longevity in physically healthy older adults. However, further research is needed to determine whether the lower body temperature observed in long-lived individuals is linked to specific health advantages, such as enhanced immune function, absence of detrimental factors or diseases, or a reduced metabolic rate potentially influenced by caloric restriction.

2nd Department of General Surgery and Surgical Oncology Medical University Hospital 50 556 Wroclaw Poland

Center of Assisted Reproduction Department of Obstetrics and Gynecology University Hospital and Masaryk University 625 00 Brno Czech Republic

Department of Hygiene and Epidemiology Collegium Medicum University of Zielona Góra 65 046 Zielona Góra Poland

Department of Veterinary Surgery Institute of Veterinary Medicine Nicolaus Copernicus University 87 100 Toruń Poland

Division of Anatomy Department of Human Morphology and Embryology Faculty of Medicine Wroclaw Medical University 6a Chalubinskiego Street 50 368 Wrocław Poland

Prestige Department of Poultry Science College of Agriculture and Life Sciences North Carolina State University Raleigh NC 27695 7608 USA

References provided by Crossref.org