Caffeine affects everyone differently – your weight, genes, gender, and even medication regimen all play a role — but this much is more or less universally true: You don’t want to overdo it. Whatever your threshold is, crossing it can come with such unpleasant side effects as jitters, stomach pain, and insomnia.
If you rely on coffee to help transform you into a functioning human each day, it’s tempting to think of more as better: A cup or two in the morning to get you started, plus a few more whenever you’re having trouble staying alert and on task. But research suggests you can get the same benefits from your daily caffeine boost by thinking about it more strategically. According to a study published in November in the journal Frontiers in Psychology and recently highlighted by Mental Floss, coffee’s memory-boosting powers are at their most potent at a specific point during the day.
The study authors recruited a group of college students to complete a memory task where they viewed and later recalled groups of words. Some of the volunteers were assigned to an early-morning session, arriving at 6 a.m., while others went into the lab at two in the afternoon. In each round, participants started by rating how awake they felt; half of the students were given a regular cup of coffee before they started the memory task, while the other half received a decaf cup they were told contained caffeine. Once the whole thing was finished, they again reported how awake they were feeling.
The hour of the lab session made a big difference: Among those who came in the afternoon, the coffee didn’t do much to help boost their memory. For the morning group, though, those who had a caffeine jolt performed significantly better than those who drank decaf — suggesting, the study authors argued, that coffee’s success as a memory aid depends largely on how with-it you already are. If you’re reasonably bright-eyed and bushy-tailed, you’d do just as well to skip it; where it really comes in handy, it seems, is in getting your brain from a mildly zoned-out state up to baseline.
“The idea is that if people are already at their optimal, some caffeine is not going to further increase performance,” lead author Stephanie Sherman, a psychology researcher at Boston University, told Mental Floss. “Caffeine only helped when you’re at your low point in the day of physiological arousal and performance.” If you’re really not a morning person, coffee really is like a best friend: loving you most when you’re at your grumpiest.