Science Daily: Researchers examine the decline in average body temperature among healthy adults over the past two decades
Real science is never settled, and anyone who has certainty on such things is not qualified to discuss it — Lloyd Chambers. That applies to climate science, COVID-19, and Einstein’s theory of relativity.
Medical “facts” are anything-but. Here is an example of how even things that should be trivial to establish cannot be explained.
Researchers examine the decline in average body temperature among healthy adults over the past two decades
In the nearly two centuries since German physician Carl Wunderlich established 98.6°F as the standard "normal" body temperature, it has been used by parents and doctors alike as the measure by which fevers -- and often the severity of illness -- have been assessed.
Over time, however, and in more recent years, lower body temperatures have been widely reported in healthy adults. A 2017 study among 35,000 adults in the United Kingdom found average body temperature to be lower (97.9°F), and a 2019 study showed that the normal body temperature in Americans (those in Palo Alto, California, anyway) is about 97.5°F.
"The provocative study showing declines in normal body temperature in the U.S. since the time of the Civil War was conducted in a single population and couldn't explain why the decline happened," said Gurven. "But it was clear that something about human physiology could have changed. One leading hypothesis is that we've experienced fewer infections over time due to improved hygiene, clean water, vaccinations and medical treatment. In our study, we were able to test that idea directly. We have information on clinical diagnoses and biomarkers of infection and inflammation at the time each patient was seen.
While some infections were associated with higher body temperature, adjusting for these did not account for the steep decline in body temperature over time, Gurven noted. "And we used the same type of thermometer for most of the study, so it's not due to changes in instrumentation," he said.
WIND: I often run at below 98°F and I often run hotter too, for hours, particularly at night. If they tested me, they’d get wildly variable results depending on when measured!
This is just another example of “scientific truth” being far from it, for two centuries. Nor is it clear to me that this new study is more than bunk, given my own known variabilityon top of the many factores cited:
"Another possibility is that our bodies don't have to work as hard to regulate internal temperature because of air conditioning in the summer and heating in the winter," Kraft said. "While Tsimane body temperatures do change with time of year and weather patterns, the Tsimane still do not use any advanced technology for helping to regulate their body temperature. They do, however, have more access to clothes and blankets."
The researchers were initially surprised to find no single "magic bullet" that could explain the decline in body temperature. "It's likely a combination of factors -- all pointing to improved conditions," Gurven said.
Alright then. How about nutrient deficiencies, sedentary lifestyles and all the stuff researchers did not think of?
But by linking improvements in the broader epidemiological and socioeconomic landscape to changes in body temperature, the study suggests that information on body temperature might provide clues to a population's overall health, as do other common indicators such as life expectancy. "Body temperature is simple to measure, and so could easily be added to routine large-scale surveys that monitor population health," Gurven said.
Ummm... what time of day? I see 2°F variations or more some days. Shouldn’t someone have a thermometer up their ass 24 X 7 for a few weeks?