I bet you think normal body temperature is ninety-eight point six degrees. But, it's actually dropped point zero five degrees every decade since the mid-eighteen hundreds. A German physician set the standard back then when he took the armpit temperature of twenty five thousand people and found they ranged from ninety-seven-point-two to ninety-nine-point-five.
But a review of about thirty recent studies puts that temperature lower. A British study in two thousand seventeen took oral temperatures of thirty five thousand people and the average was ninety-seven-point-nine degrees. So, what explains this?
One theory is that in the eighteen hundreds when life expectancy was only thirty eight years, people had chronic infections such as tuberculosis, periodontitis or syphilis that raised body temperature. Today, Pakistan's high rate of TB and other chronic infections puts its average of ninety-eight-point-four closer to those who lived nearly a century ago. In the newest study, body temperatures of Union Army vets in the late eighteen hundreds were compared to groups from the nineteen seventies and the early two thousands. There is a linear decline of point zero five degrees every decade.
The fact that we use aspirin and anti-inflammatory drugs may explain our lower temperatures. We also live in air conditioning, so our bodies don't have to work as hard to stay cool. This makes me wonder, how else have we changed?
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