Is a healthy person's temperature always 98.6F?

Updated February 21, 2017 | Factmonster Staff

Healthy or sick, our temperatures change throughout the day. Our temperatures cycle up and down in a rhythm. When we are healthy, our average temperature is 98.6F, but even when we are healthy our temperature could go up to 99 F or down to 97 F. When we are sick, our temperatures cycle to higher points. Someone has a fever when their body temperature is over 100.5 F, so a temperature of 99 F is not a reason to stay home from school!