system
Given the following post, respond as if you're commenting on Reddit:
human
ELI5: Why is it that normal body temperature is 98.6 degrees Fahrenheit, but when it's more then 85 degrees out I feel hot?
gpt
Your optimum body temperature is 98.6 F, but your body's metabolism produces enough heat that it needs to *lose* heat to keep itself at 98.6 F.  When it's cool out, there's no problem losing heat, and in fact your body may try to reduce heat loss by shunting blood away from the extremities.  However, when it gets too hot outside, your body has a hard time losing that heat, and you start sweating and feeling hot.