Time to redefine normal body temperature?

In this study, researchers analyzed temperature recordings from three periods of time over 157 years: 1860–1940: A mix of armpit and oral temperatures of nearly 24,000 veterans of the Civil War were measured. 1971–1975: Oral temperatures of more than 15,000 people from a large population study (the National Health and Nutrition Examination Survey) were analyzed. 2007–2017: Oral temperatures of more than 150,000 people in another large research project (the Stanford Translational Research Integrated Database Environment) were reviewed. During the nearly 160 years covered by the analysis, the average oral temperature gradually fell by more than one degree. As a result, the “new normal” seems closer to 97.5˚ F. This observation held up even after accounting for age, gender, body size, and time of day. Why would average body temperature be falling? Two key possibilities are: Lower metabolic rate: One of the biggest determinants of body temperature is your metabolic rate. Like a car engine that’s idling, your body expends energy just keeping things going, and that generates heat. A lower metabolic rate in modern times could be due to higher body mass (some studies link this with lower metabolic rate), or better medical treatments, preventive measures, and overall health. Lower rates of infection and inflammation: In Wunderlich’s day, tuberculosis, syphilis, chronic gum disease, and other inflammatory conditions that can raise body temperature were common, and tre...
Source: Harvard Health Blog - Category: Consumer Health News Authors: Tags: Children's Health Cold and Flu Men's Health Women's Health Source Type: blogs