PT  - JOURNAL ARTICLE
AU  - Myroslava Protsiv
AU  - Catherine Ley
AU  - Joanna Lankester
AU  - Trevor Hastie
AU  - Julie Parsonnet
TI  - Decreasing human body temperature in the United States since the Industrial Revolution
AID  - 10.1101/729913
DP  - 2019 Jan 01
TA  - bioRxiv
PG  - 729913
4099  - http://biorxiv.org/content/early/2019/08/08/729913.short
4100  - http://biorxiv.org/content/early/2019/08/08/729913.full
AB  - In the US, the normal, oral temperature of adults is, on average, lower than the canonical 37°C established in the 19th century. We postulated that body temperature has decreased over time. Using measurements from three cohorts--the Union Army Veterans of the Civil War (N=23,710; measurement years 1860-1940), the National Health and Nutrition Examination Survey I (N=15,301; 1971-1975), and the Stanford Translational Research Integrated Database Environment (N=150,280; 2007-2017)--we determined that mean body temperature in men and women, after adjusting for age, height, weight and, in some models date and time of day, has decreased monotonically by 0.03°C per birth decade. A similar decline within the Union Army cohort as between cohorts, makes measurement error an unlikely explanation. This substantive and continuing shift in body temperature—a marker for metabolic rate—provides a framework for understanding changes in body habitus and human longevity over the last 200 years.