That first steaming mug on the nightstand might be badly timed. Daily cortisol, the stress hormone that spikes as you wake, already drives arousal through the hypothalamic pituitary adrenal axis. Pouring caffeine on top of that peak can blunt its impact, increase tolerance, and set you up for a sharper crash later in the day.Far smarter is a small delay. Around sixty to ninety minutes after waking...More