Normal Human Body Temperature Is No Longer 98.6 Degrees

The human body is getting colder

Human body temps are dropping.

For years, medical professionals, parents and kids hoping to stay home sick from school have looked to one magic number when it comes to assessing health vs. illness: 98.6.

That number, in degrees Fahrenheit, has long been held as normal human body temperature, as determined nearly 150 years ago by  German physician Carl Reinhold August Wunderlich, who analyzed temperatures from 25,000 patients and published the precedent-setting findings in 1869.

Over a century later, however, it seems Wunderlich’s findings no longer hold true. According to the Wall Street Journal, a new study from Stanford University argues that while Wunderlich’s analysis was correct at the time, the average human body temperature today has dropped to 97.5 degrees.

While the researchers aren’t sure why the drop has occurred, it would seem the human body itself has simply changed over time. As the paper’s senior author, Julie Parsonnet, noted, “People are taller, fatter and live longer.” And while Parsonnet added that researchers are unsure exactly what’s behind those changes, it’s clear that temperature is connected. “The question is which is driving the others.”

Parsonnet and her team at Stanford analyzed 677,423 temperatures collected from 189,338 individuals over a span of 157 years, finding not only that human body temperatures had declined, but that they have been declining steadily for decades. The researchers found that temperatures recorded from Civil War vets were higher than those gathered by the U.S. Centers for Disease Control and Prevention from 1971 through 1974, which were in turn higher than temperatures recorded in the 2000s.

“Two things impressed me,” Parsonnet said. “The magnitude of the change and that temperature has continued to decline at the same rate.”

While a difference of about one degree may seem marginal, Philip Mackowiak, emeritus professor of medicine at the University of Maryland School of Medicine, called it a “huge drop for a population.”

Whatever the reason, humans are cooling off. Maybe it’s our weight, maybe it’s our height or maybe it’s just the growing postmodern consensus that we’re all dead inside (and dying on the outside!)

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