Hard time sleeping

Veterans Day—and a study that's about sleep but is also really about military life. Also, 7 other things worth your time.

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Today is Veteran’s Day. So, I’d like to say thank you to all who served. Then, I’d like to switch gears and share a study on life in the military.

It’s about sleep deprivation, which the CDC says 40 percent of U.S. service members suffer from, averaging less than five hours of sleep on a normal night. They get less during training, deployments, and of course in combat.

So, the military spent more than a decade studying how to get by on habitually little sleep, and researchers say they figured out a mathematical formula that can help anyone—military or civilian—determine the optimal amount of caffeine they need in order to stay alert.

I spoke with Dr. Jaques Reifman of the U.S. Army Medical Research and Materiel Command in Fort Detrick, Maryland, co-author of the latest research, which was published in the aptly named journal, Sleep (pdf link).

“This is leveraging 10 years of research on sleep deprivation,” Reifman told me. “How do humans respond to continuous sleep deprivation of 60 hours? How is that different from when you sleep three hours a night for 10 days? ... What we're dong here now is to develop math equations that describe the phenomenon.”

Specifically, they're coming up with two things:

  • an algorithm that can say how much caffeine the “average” sleep-deprived person needs, in order to be as alert as if they typically got eight hours of sleep, and

  • a way to determine specifically, person-by-person in almost real time, what any particular amount of caffeine will do to their level of alertness.

Here are a few examples of what the “average” sleep-deprived person in various situations would have to consume to achieve the same level of alertness they'd have with eight hours of sleep:

  • Getting by on five hours of sleep a night? You might need to consume the equivalent of two cups of weak coffee when you wake up, followed by another two cups, four hours later.

  • Getting reasonable amounts of sleep, but you're working an occasional overnight shift? You'd be best off drinking a quick two cups of weak coffee right at the start of your shift.

  • And, if you're expecting you won't be able to sleep much at all for more than a day or two, you're supposed to drink the equivalent of two cups of coffee at midnight, then again at 4 a.m., and then at 8 a.m."

The “weak cup of coffee” we're talking about has about 100 milligrams of caffeine.

(For any military folks reading this: an 8-ounce can of Rip It energy drinks, which are hugely popular in the U.S. Army—or at least, they were as of a little over a decade ago, when I was last associated—has about 80 milligrams of caffeine.)

Reifman told me the goal here is to squeeze the maximum benefit from the caffeine you're consuming, while making sure the total caffeine in your bloodstream doesn't exceed a threshold of 400 milligrams at any one time.

The algorithm that Reifman and his colleagues came up with is proprietary, so the second part of their goal—the part where they can tell any person specifically how much caffeine he or she should drink to maximize alertness—isn't something you can use right now.

"The military is trying to license that," Reifman told me. Ultimately, he hopes to build something much more robust, that could tell individual soldiers in the field when to consume caffeine so as to achieve maximum alertness in battle.

It’s funny. This study might go down as the latest innovation that was pursued to support the military, but wound up benefiting civilians even more. Think of the jeep, the jet airplane, penicillin, and now (or at least, soon): the caffeine calculator.

Anyway, I share this study because it’s potentially useful for those of us who are often sleep-deprived (although ironically, I’d say I’m doing better during the pandemic than before it).

But I’m also sharing it because I think people tend to think of military sacrifice as involving the big things: risking life or limb, spending long times away from family, etc.

So this is a reminder on Veterans Day that there are other, smaller sacrifices in the background, too: more pedantic things like getting by on not-enough-sleep for long periods of time.

7 other things worth your time

Photo credit: Official U.S. Army photo. I wrote about this study previously for Inc.com. If you liked this post, and you’re not yet a subscriber, what are you waiting for? Please sign up for the daily Understandably.com email newsletter, with thousands and thousands of 5-star ratings from happy readers. You can also just send an email to signup@understandably.com. 

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