Frequent doses of short-term stress is a good and necessary thing for life.

However…
Over-thinking is a form of stress.
Over-work is a form of stress.
Another way to look at over-work is that under-sleep/rest/recovery is stress.
Bad nutrition is stress.
Over feeding is stress.
Bad environment is stress.
Bad friends/family/work is stress.
Again, over-thinking is stress.
Not thinking enough will probably lead to stress.

To reiterate, regular doses of short-term stress is normal and healthy. It’s the overdose of stress that we must be wary of.

Anyway, here is Dr. Gabor Maté and the bio-psycho-social model of health, and how stress gone wild leads to disease.