weekly blog--one for the ages
This week the temperature on planet Earth was probably raised several degrees from the heat generated by people worried that the latest US-Iranian confrontation would lead to an all-out war. But did you know that since the early 19th century, the average human body temperature in the United States has dropped to 97.9 from 98.6 F.
Researchers at Stanford University observed that the body temperature of men born in the 2000s is on average 1.06 F lower than that of men born in the early 1800s. Similarly, they observed that the body temperature of women born in the 2000s is on average 0.58 F lower than that of women born in the 1890s. These calculations correspond to a decrease in body temperature of 0.05 F every decade. The 98.6 standard was established by a German physician in 1851.
According to the researchers, the decrease in average body temperature could be explained by a reduction in metabolic rate, or the amount of energy being used. They hypothesize that advances in medical treatments, better hygiene, improved standards of living, and greater availability of food reduce inflammation. Inflammation produces proteins and cytokines that increase your metabolism and raise your temperature.
The researchers also hypothesize that comfortable lives at constant ambient temperature contribute to a lower metabolic rate. Homes in the 19th century had irregular heating and no cooling; today, central heating and air conditioning are commonplace. A more constant environment removes a need to expend energy to maintain a constant body temperature.