The U.S. Army calculates exact amount of coffee necessary for alertness

The U.S. Army has finally relieved of us of that nagging midmorning dilemma, the one in which you debate: Should I have another cup of coffee?

Caffeine stimulates the central nervous system, making one feel more energized, awake, and ready to battle the onslaught of “brainstorming” meetings. It’s why it’s the most commonly used psychoactive drug in the world. It’s estimated that 83% of Americans drink coffee, and nearly 45% drink two to three cups a day. (The Mayo Clinic advises no more than four daily, with side effects including insomnia, nervousness, irritability, and “frequent urination or inability to control urination.”)

But as to how much caffeine will keep you focused–versus spiraling into jitters–has mostly remained an imperfect science. The U.S Army, presumably in an attempt to help staff and soldiers during long shifts, commissioned a study to analyze the precise, most effective use of caffeine. On Monday, researchers announced an automated optimization algorithm to identify the strongest caffeine-dosing strategies to “maximize alertness” during sleepy conditions. A recent study found a shockingly high prevalence of sleep disorders among active duty military personnel.

“We found that by using our algorithm, which determines when and how much caffeine a subject should consume, we can improve alertness by up to 64%, while consuming the same total amount of caffeine,” said Jaques Reifman, PhD, a senior research scientist and director at the U.S. Army Medical Research and Materiel Command. “Alternatively, a subject can reduce caffeine consumption by up to 65% and still achieve equivalent improvements in alertness.” The study was published in the peer-reviewed Journal of Sleep Research.

The algorithm combines user-input data on an individual’s physiology and maximum caffeine allowance with psychomotor vigilance task (PVT) tests, a tool used to measure a person’s behavioral alertness, reports Government Technology. The more data it gathers, the more it can better predict not just much how much, but what exact time you should drink coffee to be more productive. It also calculates how to optimize results while reducing overall caffeine intake.

The study’s methods are reportedly being used on soldiers in training, but there’s talk the Army will ultimately license the technology. It might even be further developed to automatically log sleep data and connect with fitness devices. For the time being, a more limited version of the ultimate app is available as the 2B-Alert mobile app.