Why You Shouldn't Drink Coffee In The Morning

Are you thinking of that first sip of coffee before your feet hit the floor? You might be overriding your body's natural waking process.

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.

Hat tip: Forbes and I Love Coffee

Click to expandInfographic by Ryoko

[Image: Flickr user Seth Anderson]

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  • Oh wow, I guess I never really considered that - I just know that I need some kind of boost in the morning. I'm actually trying to become less dependent on caffeine - I imagine that starting later in the morning, and then only one cup instead of two, would probably be a good way to start. Thanks!

  • I had no Idea when to drink coffee till I read this informative text.Because I used to drink whenever I want, but now I know. Thank you very much for sharing your good work. Bezy

  • You list the time for production of cortisol as 0800-0900, what sleep schedule is this based? If you wake up at 0500, is the production time the same as waking up at 0800?

  • Good to know! I generally drink my coffee between 9:30am and 11:30 am and will now pay attention to Java timing. Food (or drink) for thought: does that apply to decaf coffee? That's the only kind I drink. I gave up even decaf after 6pm. However, I've not seen one bit of difference in my sleep patterns... or lack thereof.

  • What about people who don't drink coffee because they need a stimulus, they drink coffee because they like it. I don't really care about cortisol levels, I just want to drink coffee in the morning. Sometimes I like to drink coffee after lunch. Sometimes I have a coffee when I get home from work in the evening. It's about when I want to drink coffee.

  • Vitz Vitz

    what about people who's circadian rhythms fall outside the 'norm'? the notion that everyone has the same circadian rhythm is rubbish, and 'bad science'.

  • Arturo Aragón Fournier III

    but this is all supposing we wake up at regular office hours, correct ? What about people who have unusual hours?

  • Freddy Rodriguez

    Eye-opening. I'm not a heavy coffee drinker, but I do like learning about how to tweak my lifestyle to get optimal performance. Love the infographic. Thanks for sharing.