Let’s get one thing straight here. I love my morning cup of joe. I’m not alone in saying my day doesn’t start without it. Sixty percent of American coffee drinkers claim they need coffee to start their day.
But when I came across an infographic by Ryoko Iwata, a Japanese coffee-lover with a blog titled "I Love Coffee" who followed research on the 24-hour circadian clock gathered by Steven Miller, a PhD candidate at the Uniformed Services University of Health Sciences in Bethesada, I decided to change my ways. The infographic shows the early morning hours are the worst time to drink coffee.
While all of us have different reactions to caffeine, our bodies are all guided by the 24-hour hormonal cycle called the circadian clock. One of the hormones this clock controls is cortisol, which makes us feel alert and awake. The peak production time of cortisol is between 8 and 9 a.m. If you're a morning coffee drinker, this means you're consuming caffeine at a time when your body is essentially naturally caffeinating itself.
Drinking coffee at peak cortisol times not only diminishes the energy-boosting effects of caffeine, but causes your body to build a tolerance to it, meaning the caffeine jolt you get will diminish over time. Timing your coffee breaks with your body’s cortisol schedule means you will get the biggest bang from your caffeine jolt. According to the infographic, cortisol levels peak between 8 to 9 a.m., 12 to 1 p.m. and 5:30 to 6:30 p.m., meaning the best time for a coffee break is between 9:30 to 11:30 a.m. and 1:30 to 5 p.m., when our body’s cortisol levels drop.
What about those of you who wake up at 5 a.m. and have their first cup of java well before 8? Although the release of cortisol is mostly controlled by sunlight, levels of cortisol increase by about 50% upon awakening. So even early risers don't need caffeine immediately upon jumping out of bed, but can benefit from having their first cup about an hour after waking.