Is older colder or colder older? The association of age with body temperature in 18,630 individuals

• Published in: The journals of gerontology. Series A, Biological sciences and medical sciences Vol. 66; no. 5; pp. 487 - 492
• Main Authors: Waalen, Jill, Buxbaum, Joel N
• Format: Journal Article
• Language: English
• Published: United States Oxford University Press 01-05-2011
• Subjects: Adult; Aged; Aged, 80 and over; Aging - physiology; Biomarkers - analysis; Body Mass Index; Body temperature; Body Temperature - physiology; Cross-Sectional Studies; Female; Genetics; Gerontology; Humans; Journal of Gerontology: BIOLOGICAL SCIENCES; Leukocyte Count; Leukocytes; Longevity - physiology; Male; Measurement; Middle Aged; Older people; Women
• ISSN: 1079-5006; 1758-535X
• DOI: 10.1093/gerona/glr001

In animal studies, caloric restriction resulting in increased longevity is associated with a reduction in body temperature, which is strain specific and likely under genetic control. Small studies in humans have suggested that temperatures may be lower among elderly populations, usually attributed to loss of thermoregulation. We analyzed cross-sectional data from 18,630 white adults aged 20-98 years (mean 58.3 years) who underwent oral temperature measurement as part of a standardized health appraisal at a large U.S. health maintenance organization. Overall, women had higher mean temperatures (97.5 ± 1.2°F) than men (97.2 ± 1.1°F; p < .0001). Mean temperature decreased with age, with a difference of 0.3°F between oldest and youngest groups after controlling for sex, body mass index, and white blood cell count. The results are consistent with low body temperature as a biomarker for longevity. Prospective studies are needed to confirm whether this represents a survival advantage associated with lifetime low steady state temperature.