There are studies in caffeine and sleep disorder, anxiety disorder, addiction and cardiovascular issues around. So it’s quite subjective!
Discussion
Ok and there are plenty of them telling that it delays dementia and Alzheimer's, prevents cancer, and much more. If it's a normal intake you won't have a problem, putting it alongside alcohol and nicotine is my issue.
It can be both! Depends on your individual needs / circumstances!
And mostly how much you take for then to be a problem, if it's your normal coffee consumption you'll get the benefits and none of the damages.
There might be people with any healthy caffeine threshold! Is quite individual!