98.6 Degrees Fahrenheit Isn’t the Average Anymore

schwit1 shares a report from The Wall Street Journal: Nearly 150 years ago, [German physician Carl Reinhold August Wunderlich] analyzed a million temperatures from 25,000 patients and concluded that normal human-body temperature is 98.6 degrees Fahrenheit. In a new study, researchers from Stanford University argue that Wunderlich’s number was correct at the time but is no longer accurate because the human body has changed. Today, they say, the average normal human-body temperature is closer to 97.5 degrees Fahrenheit (Warning: source paywalled; alternative source). To test their hypothesis that today’s normal body temperature is lower than in the past, Dr. Parsonnet and her research partners analyzed 677,423 temperatures collected from 189,338 individuals over a span of 157 years. The readings were recorded in the pension records of Civil War veterans from the start of the war through 1940; in the National Health and Nutrition Examination Survey I conducted by the U.S. Centers for Disease Control and Prevention from 1971 through 1974; and in the Stanford Translational Research Integrated Database Environment from 2007 through 2017. Overall, temperatures of the Civil War veterans were higher than measurements taken in the 1970s, and, in turn, those measurements were higher than those collected in the 2000s. The study has been published in the journal eLife.