New research shows that the human body uses 30% to 50% less water per day than chimpanzees, gorillas, bonobos and orangutans .
For the first time, how much water humans lose and replace each day has been accurately measured compared to our primate cousins.
Sweat glands
The study compared the water turnover of 309 people with a variety of lifestyles, from farmers and hunter-gatherers to office workers, with that of 72 apes. Water intake was calculated through food and drink, on the one hand, and water lost through sweat, urine, and gastrointestinal tract. The average person processes about three liters, or 12 cups, of water per day. A chimpanzee or gorilla living in a zoo suffers twice as much .
Our bodies are constantly losing water: when we sweat, we go to the bathroom, even when we breathe. That water must be replenished to maintain the volume of blood and other bodily fluids. But an ancient change in our body’s ability to conserve water .
As lead author Herman Pontzer , associate professor of evolutionary anthropology at Duke University explains:
Even just being able to go a little longer without water would have been a huge advantage when the first humans began to make a living in the dry landscapes of the savannah.
The next step, says Pontzer, is to pinpoint how this physiological change occurred. At the moment, only some hypotheses are being considered,