#11: Sleep & Caffeine Part 2

A cup of coffee in the evening can decrease the amount of that deep non-rapid eye movement sleep by somewhere between 20-40% at night. And for a spot of context, I'd have to age a healthy adult by probably about 10-15 years to produce that kind of a reduction in deep sleep.

Recommendations typically suggest limiting yourself to somewhere between 1-3 cups of coffee each day. And, ideally, try to cut your caffeine consumption off at least 12 hours before you wish to go to bed at night.

Even modest doses of caffeine in the evening—let's say, around about 100 mg of caffeine in the evening, which would be probably a robust single cup of drip coffee—that will blunt the electrical generation of your deep sleep. And in fact, it will strip away more than 30% of that deep electrical brain wave activity in the first cycle of your sleep at night.

Coffee ends up being the single biggest source of antioxidants for many people in developed nations—and not by a small margin either.

Even if you can have a cup of coffee, or several, with dinner and you can fall asleep and stay asleep, you can still suffer impairments in both the quantity as well as the electrical quality of your deep non-rapid eye movement sleep.

It's these antioxidants that we believe are the principal explanation for why coffee is associated with so many health benefits. It's not the caffeine itself; it's the antioxidants associated with the coffee bean.