"Definitely limit coffee when you first wake up," Laura Cipullo, registered dietitian and author of Women's Health Body Clock Diet, told CNBC. She says this, because your body produces the largest amount of cortisol when you wake up. Cortisol is otherwise known as the stress hormone since it's commonly associated with fear, fatigue, and anxiety.
Here's the thing: Cortisol is known to increase in the presence of caffeine, so pairing your body's natural cortisol with that which comes from your morning coffee might make you feel jittery and anxious.
We don't know about you, but that's not an ideal way to start our day. Then, when the heightened levels of cortisol wear off, you can feel depleted and fatigued all over again. (In other words, you could hit the dreaded afternoon wall of tiredness while still sitting at your desk with work piling up.)
This is why some experts recommend putting off your first cup of coffee. "Have coffee when the body is producing less cortisol, about three to four hours after waking," Cipullo said. Certified dietitian and nutritionist Lisa Lisiewski agreed, telling CNBC, "I would say that mid-morning or early afternoon is probably the best time. That's when your cortisol levels are at their lowest and you actually benefit from the stimulant itself."
There you have it. No matter how sad the thought may be, it looks like I'll be waking up sans-coffee starting now. Only once I'm ready for the day, and three hours have passed, will I hit the magical coffee pot button.