One data point: A couple of years ago, I went coffee-free for one month, just to see what it would do to me. Sucked. I like coffee for the sake of coffee. But

One data point: A couple of years ago, I went coffee-free for one month, just to see what it would do to me. Sucked. I like coffee for the sake of coffee. But was happy to see "I could do it". Could not observe any significant change in my life. Maybe felt a little less "up". I ended the experiment after one month. I don't drink/do drugs (besides coffee).