This Is The Best Time To Drink Your Coffee, According To Science

When cortisol, a hormone associated with alertness, dips, you'll start feeling drowsy. That's the moment to caffeinate.

If you're anything like certain members of the Fast Company staff, then you feel more or less undead until you have your morning cup of brains coffee. However, insight into the way our attention rises and dips throughout the day suggests that we can get more precise about the way we caffeinate—and thus become more productive.

How so? Because, as Steven Miller, the man behind brain blog NeuroscienceDC suggests, the way coffee affects your body is shaped by a few key factors. Those being:

  • Caffeine is a drug
  • Your body has rhythms, hormonal and otherwise
  • To use a drug wisely, you fit it to your rhythms

How do those points combine? To understand, Miller asks us to consider the insights of chronopharmacology, the study of the interaction between drugs and biological rhythms.

Your body has many rhythms: there's the circadian one that drives your sleeping habits (and gets messed up by over-zealous snoozing), the ultradian one that tells us to unplug every 90 minutes, and most interestingly for our caffeinated purposes, the rhythm of the release of cortisol.

The character of cortisol

Cortisol is a hormone that's gained a bad name: often referred to as the "stress" hormone, it increases the amount of sugar in your bloodstream and heightens your brain's use of glucose, among other action-ready, danger-facing functions. If you're releasing cortisol all the time—as chronically stressed people do— it can be super bad for you, since all that glucose can lead to diabetes and other nasty diseases.

However, cortisol isn't always terrible: as Miller notes, your cortisol correlates to your alertness levels. And when is cortisol at its highest? As a University of Sheffield study has shown, you have the most cortisol between the hours of 8 a.m. and 9 a.m.

So if you take a cup then, it's a tad redundant. As Miller explains:

... you are drinking caffeine at a time when you are already approaching your maximal level of alertness naturally. One of the key principles of pharmacology is use a drug when it is needed (although I’m sure some scientists might argue that caffeine is always needed). Otherwise, we can develop tolerance to a drug administered at the same dose. In other words, the same cup of morning coffee will become less effective

There are other cortisol peaks throughout the day, like between noon and 1 p.m. or between 5:30 and 6:30 p.m. The savvy coffee drinker, then, will enjoy her brew when her natural alertness levels are low, like between 9:30 and 11:30 am—that way you can get the most bang for your cup.

Hat tip: NeuroscienceDC

[Image: Flickr user Moyan Brenn]

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  • Michael Sterling

    Into which timezone are you implying? My day starts at 2 a.m. in my local time zone, because it corresponds to 8 a.m. in the part of the world I work. Since the general timeline implied will not work unless you know your timed cycle, how does one discover their personal rhythm?

  • Jim Collins

    However, if the decision of when to ingest caffeine is being considered by said scientists, it is reasonable for them to consider when in their f'ed up circadian cycle the caffeine might be most productive in the long run. Consider, for instance:
    for information on the use of "cognitive enhancement drugs" by scientists. I'm competing with these mofos, and devil take the hindmost.

  • Steven Miller

    , the patients in the study were sampled for blood cortisol levels every 20 min over a 24-hr period so they were not subject to a typical 'work' schedule. I believe applying this information to a typical 9-5 rhythm is a fair thing to do. Most scientists I know probably have a pretty messed up cortisol rhythm and that's why we drink coffee/soda all day.

  • Carl Setzer

    Base assumption: subject work/life rhythm based on 9:00-5:00 work schedule.