There are many factors, which act as stressors on the body, and seem to contribute to improved health outcomes. Some of these include:
Exercise
Fasting
Cold exposure
Caloric restriction
Heat exposure
Particular foods that exert hormetic effects (ie. cruciferous vegetables)
Some of the above are not without their controversies, but it's interesting that mild sleep deprivation (a mild stressor) doesn't elicit a hormetic effect. Or perhaps it does?
Has anyone else had this curious thought before and unpacked it a little?