| Espresso martinis are everywhere these days — at restaurants, in the news and on TV. Even my last flight served a canned version. Prepared coffee cocktail sales are up 8% at US retailers over the past year alone, according to researcher NIQ. They’re also among the fastest-growing cocktails for people dining out. My favorite rendition can be found at Truce, an award-winning bar and coffee shop in Chicago. Espresso martinis are by far the most popular drink on their menu, with at least 75 orders a night on the weekend. Truce’s recipe features vodka, grappa, cacao, Licor 43, coffee liqueur, orange, salted demerara and a shot of espresso — all infused with nitrogen to create a rich, foamy concoction with a hint of citrus.  An espresso martini at Truce. Photographer: Catherine Larkin/Bloomberg “It’s the first drink that a lot of people will order,” says Sarah Kmiec, one of Truce’s owners. “You don't necessarily taste alcohol, you taste like this amazing coffee drink, this latte that reminds you of waking up and being productive. So it feels like you’re on your way to a productive night.” Sales of espresso martinis at bars and restaurants peak in the 9 p.m. hour, according to Union, a hospitality tech company that tracks industry trends. One of my friends likes to joke that she’ll be in bed before the caffeine hits her, but I’ve long wondered what kind of impact this late-night buzz is having on my sleep. I posed this question to Khaled Almadhoun, a sleep medicine physician with Henry Ford Health in Michigan. He says for people with normal sleep patterns, the roughly 60 milligrams of caffeine in one espresso martini aren’t likely to have a noticeable effect. But people with a history of insomnia may want to think twice about them, even as an aperitif. “If you have trouble falling asleep, we don’t recommend caffeine anytime in the afternoon,” Almadhoun says. “Nothing at dinner and afterwards.” That’s because caffeine reaches its maximum effect as quickly as 30 minutes after you ingest it, and it can stay in the body for at least five to six hours, he says. It’s most potent late at night because that’s when the brain has higher levels of adenosine, a chemical that causes drowsiness that can be muted by caffeine. Almadhoun says most adults don’t get the recommended 7 to 9 hours of sleep, and caffeine can be a factor when you end up with a restless night. Sleep is very individualized and tolerance to caffeine will differ. Some studies even suggest that one cup of coffee can affect sleep more than 8 hours later. The buzz from caffeinated workout supplements can last more than 13 hours. Pairing caffeine with alcohol is “like a double whammy,” according to Almadhoun. Caffeine prevents you from falling asleep, and alcohol prevents you from staying asleep. In other words, don’t buy your friend’s argument that alcohol will counteract the effect of caffeine, or vice versa. It’s also worth noting that some espresso martini fans don’t stop at just one. Kmiec says she’s seen someone have four in one sitting. That can quickly add up to more caffeine than your regular Starbucks order. That’s a lot to think about before ordering a cocktail. Thankfully, some bars like Truce offer decaf espresso martinis. Kmiec says they get at least one decaf order every night. The downside: Truce’s decaf martinis lack the bells and whistles of the original since the nitrogen version is made in advance in batches. Another potential option is to enjoy your espresso martinis earlier in the day so the caffeine has time to wear off. Truce’s frequently asked questions online includes one about whether cocktails are available at breakfast. The answer? “Absolutely.” — Catherine Larkin | 
