May 29, 2015 12:17 PM EDT

Many coffee drinkers probably reach for their morning cup of joe immediately after waking up, but this video from AsapSCIENCE reveals that that’s not really the best idea if you want to maximize your levels of energy and alertness.

The main factors at play are your body’s circadian rhythm and the times when your body produces the hormone cortisol, which affects your level of alertness throughout the day.

The video’s narrator explains that 9 a.m. is probably the ideal time for most people to drink their coffee, because it’s right after your body’s peak cortisol production. Watch up top to learn more.

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