Most coffee drinkers wake up and have their morning coffee right away. Some like having a cup or two at night. But the optimal times to drink coffee throughout the day aren’t in the early morning or late evening.
If you want to get the best effects from the caffeine in coffee, drinking it when your body’s cortisol levels are lowest is the best action to take.
What is cortisol?
Cortisol is a stimulating hormone the body naturally produces. Some call it the stress hormone because cortisol levels increase in response to fear or stress. Another function it has is regulating our circadian clock – the hormone cycle that manages our waking and sleeping cycles. Cortisol makes you feel more “awake.”
How does cortisol relate to caffeine?
Since cortisol has a stimulating effect, it’s similar to caffeine. It becomes a problem to drink coffee early in the morning because caffeine inhibits cortisol. The presence of caffeine in the body will significantly slow the release of cortisol, which has important functions in our body’s circadian rhythm and stress regulating mechanisms. That creates a problem.
When we drink coffee while cortisol levels are highest (early in the morning), we set ourselves up for unnecessarily high caffeine tolerance. It’s the main reason habitual coffee drinkers say one cup isn’t enough in the mornings.
Over time, when your body is flooded with caffeine just as cortisol levels are at their peak every day, you train your body to stop releasing cortisol in the proper amounts.
Because caffeine is similar molecularly to cortisol, the presence of caffeine early in the morning signals your body that there’s no need to release cortisol. That results in an unnecessarily high tolerance for caffeine simply because of the time it was consumed.
Your body’s cortisol levels peak 3 times each day:
- Early morning – 6am-10am
- Mid-day – 12pm-2pm
- Evening – 6pm-8pm
Cortisol levels were tracked and recorded in a 2009 study about caffeine tolerance. The chart below, from The Washington Post, shows the average rise and fall of cortisol levels in participants throughout the day.
When are the best times to drink coffee?
Since cortisol stimulates like caffeine, the best times to drink coffee are during the dips in cortisol levels. If you drink coffee during the periods when your body’s cortisol levels are low, you “fill in the gaps” with caffeine and feel boosted during the periods of the day when you might normally start feeling tired.
The best times to drink coffee:
While a cup of coffee first thing in the morning becomes a habit and seems hard to abandon, knowing that you’ll actually feel more boosted and less jittery while decreasing your tolerance for caffeine are good reasons to consider changing your coffee schedule. Drinking your first cup no earlier than 10am and stopping around noon, then having a cup somewhere between 2 and 5pm will keep you alert all day long without keeping you up at night.
Afternoon coffee keeping you awake?
If caffeine in the afternoon tends to keep you awake at night, as it does for many people that are caffeine-sensitive, you might be tempted to skip the second round of coffee in the late afternoon and early evening. But studies show that as long as you have your final coffee for the day at least 6 hours before bedtime, you’ll feel rested and ready for sleep. So if you usually go to sleep at 11pm, don’t have any coffee after 5 pm.