It's universally acknowledged that, for the vast majority of us, afternoon just isn't the most productive time of the day. But while everyone agrees on the existence of the after-lunch slump, prescriptions on how to beat it vary.

Naps are one oft-touted suggestion, but while science has proven they do wonders for your performance (and your memory), they're just not practical for lots of folks. Same goes for a short stint of yoga, another research-approved possibility. So if you can't physically leave your desk in the afternoon, what's the next best solution?

I am happy to report that, according to a new study, it might just be to eat more chocolate.

Cacao vs. the afternoon slump

The research (which thrills me personally) was led by Larry Stevens, a Northern Arizona University psychologist, and involved looking at the effects of eating dark chocolate on the brain, using an EEG machine to measure brain activity. What did the brain images of the 122 study participants show?

"Chocolate is indeed a stimulant and it activates the brain in a really special way," Stevens commented in the research release. "It can increase brain characteristics of attention."

But not just any chocolate will do. Dark chocolate containing 60 percent or more cacao had the most dramatic effect on attention levels. Types with more milk and sugar might be tasty but they'll do less to perk up your brain, Stevens cautions (and probably do more to expand your waistline).

The takeaway couldn't be simpler--or tastier. "A lot of us in the afternoon get a little fuzzy and can't pay attention," Stevens notes, "so we could have a higher cacao content chocolate bar and it would increase attention."

A couple of cautions

While this study is great news for confirmed chocoholics like me, there are a couple of cautions to share before you go out and stock up on your favorite brand of dark chocolate. While the snack did appear to help the brain kick it up a gear during those snoozy afternoon hours, it also raised blood pressure a bit, an effect that might worry those with health concerns. (Special chocolate that contained L-theanine, an amino acid found in green tea, managed to increase attention but not blood pressure, but as it's not on the market yet, that's currently of little practical use.)

Another caveat is that the research was funded in part by chocolate maker Hershey's, so normally I'd take the results with a certain degree of skepticism. Happily for chocolate fans, the findings are consistent with other research, however. Here, for instance, is an NPR article explaining "a study that found cocoa flavanols can help boost mood and sustain clear thinking among adults who are engaged in intense mental efforts--like students cramming, or journalists on deadline."

What's your afternoon attention booster of choice? Let us know in the comments.