What is the right amount of stress? And when is stress too much?

Nobody can tell you but yourself. It’s different for every person. In the genetically identical animal population with the same mechanisms, we still find variability. As a pup when you’re born, the amount of licking and grooming you get from your mom varies. This changes your hippocampus in a way that affects your susceptibility and response to stress. So there’s some developmental programming at utero and birth, and around the time you’re born, that then dictates how susceptible you are to stress in your life. Something super stressful for one person could be not stressful for another, and there isn’t a way to measure this. People wanted to look at cortisol in the blood and identify a certain “healthy” amount, but that doesn’t really work.