Context: According to a new study, published in the journal eLife, it has been concluded that the average human body temperature has never been constant in the first place. 


WHAT IS NORMOTHERMIA OR EUTHERMIA? Normothermia or euthermia is another name for the Normal human body temperature whose range is typically stated as 36.5–37.5 °C (97.7–99.5 °F). Body temperature is maintained within normal range by thermoregulation whereby the lowering or raising of temperature is triggered by the central nervous system. WHY 98.6°F? It was in 1851, when Carl Reinhold August Wunderlich pioneered the use of the clinical thermometer. It was a rod a foot long, which he would stick under the armpits of patients and then wait for 15 minutes (some accounts say 20 minutes) for the temperature to register.  He took over a million measurements of 25,000 patients, and published his findings in a book in 1868, in which he concluded that the average human body temperature is 98.6°F. The 98.6°F thermometer reading has been a gold standard for a century and a half, ever since a German doctor laid it down as the “normal” human body temperature. ABOUT THE RECENT STUDY Researchers from Stanford University recorded temperatures from three datasets that covers distinct historical periods. 

  • One set was from 1862-1930, with records of Union Army veterans of the Civil War and including people born in the early 1800s. 
  • Second set was from 1971-75, from the US National Health and Nutrition Examination Survey
  • The newest set was from adult patients who visited Stanford Health Care between 2007 and 2017.

With the help of 6.77 lakh measurements and statistical modelling, the researchers reconfirmed some known trends: 

  • Body temperature is higher in younger people, in women, in larger bodies and at later times of the day. 
  • It was found that the bodies of men born in the early to mid-1990s is on average 1.06°F cooler than those of men born in the early 1800s
  • The body temperature of women born in the early to mid-1990s is on average 0.58°F lower than that of women born in the 1890s.

Now, new research has found that body temperatures have, in fact, been declining over the last two centuries as a result of changes in the environment over the past 200 years.

Follow us on:



Join us on Telegram:

Print Friendly, PDF & Email