If you spend half your life getting a daily superdose of dopamine, what happens when you suddenly quit? Do you go through withdrawal, like anyone else kicking a chemical habit? Judging by Ashling’s and Zeke’s symptoms—insomnia, anxiety, mood and weight swings, acute depression—it certainly seemed a lot like they’d gone cold turkey. That hypothesis could explain why competitive athletes, who work out more than anybody else, may be nearly twice as vulnerable to depression as non-athletes. Did they pass some dangerous, invisible cutoff at which the cure became an affliction?
