Question Your World: Have we been wrong about body temperatures all along?

Posted: November 13, 2020

Everyone knows that the average human body temperature is 98.6 degrees Fahrenheit … OR IS IT?!? Have we been wrong about body temperatures all along? 

All the way back in the mid 1800s, German physician Carl Reinhold August Wunderlich established the average human body temperature as 98.6 degrees F. Since then we’ve looked for this comforting metric when sticking thermometers in our mouths and sometimes other places. 

However, for the past few decades scientists have been reexamining this topic and things are starting to heat up … well, they’re cooling down actually. For example, a 2017 study in the UK claimed their subjects have an average body temperature of 97.9°F, which is lower than Wunderlich’s findings. 

How could this be? Are humans actually evolving to have a lower temperature? If so, is it because of technological interventions like Tylenol, air conditioning, better winter jackets and so on?  

Image credit: Getty Images

To answer that question a recent study compared a group of people living in California to a group in the indigenous Tsimané tribe in the Bolivian Amazon. The folks in California had an average body temperature of 97.5°F. If our technologically built world was the culprit, then the indigenous tribe’s body temperatures should make a good control group for comparison. 

The results? The indigenous tribe had a not identical -- but close -- 97.7°F average body temperature. Well, it looks like the heralded 98.6°F average is being challenged here!

This information could be vital in better understanding the range of temperatures an individual should or should not consider healthy. For example, while a temperature reading of 99 degrees may not seem so bad initially, a jump from 97.7°F to 99°F degrees could be just as bad as going from 98.6°F to 100°F. We may need to rethink our definition of a fever! Correct temperature readings are vital in determining the next steps for treating illness, preventing the spread of a contagion and many other aspects of our health. 

This ongoing temperature exploration still requires much more research to determine if we are actually evolving or if other variables are at play here, but this is a pretty important finding as it establishes that people living with and without public health infrastructure currently have lower temperatures than the established standard. For medical scientists and Nick Lachey, the whole 98 degrees thing might just be a thing of the past.