In this season of indulgence (and overindulgence), some people will turn to the treadmill, while others turn to the Pepto-Bismol. Author Brad Thomas Parsons will reach for the bottle — specifically, a bottle full of a liqueur called amaro, which people have used as a digestive aid for centuries.

It's an herbal recipe, and "it's actually bittersweet," Parsons says.

"The bittering agents in it are actually helping your digestive system," he explains. "Four out of five doctors may not agree with everything that's working in there, but trust me."

Parsons, an expert on bitters and a James Beard Award-winning writer, has spent years digging into the history and culture of the concoction for his latest book, Amaro: The Spirited World Of Bittersweet, Herbal Liqueurs. Amaro is super-popular in parts of Europe, but not as well known on this side of the Atlantic.

"When I was in Italy researching the book and interviewing producers, I would go into stores, [and] they would have walls, floor to ceiling, of all these different amaro that I couldn't get in the States," he says.

In the U.S., Fernet-Branca is an amaro popular among discerning mixologists. More familiar to most of us is Jagermeister, that bad-decision mainstay downed by the shot in every college-town dive bar. (While many Italian producers would suggest that only the spirits produced in Italy are amari, Parsons suggests all bittersweet liqueurs fall under the category.)

An Italian family tradition transplanted to D.C.

Parsons wanted to show NPR a slightly more grown-up amaro experience, so he took All Things Considered host Ari Shapiro on a tasting tour at Don Ciccio & Figli. It's an unassuming establishment located in a Washington, D.C., warehouse with mermaid silhouettes painted on the walls. The air smells like cinnamon, eucalyptus and lemon peel, and the space is cluttered with wooden barrels and rows of glass bottles full of the rich auburn liquid made by proprietor Francesco Amodeo.

"This is actually our little house, where we live and sleep and produce some unique products," Amodeo says. He comes to the trade naturally: His family used to make amaro on the Amalfi Coast of Italy.

"Our traditions started back in 1883," he says.

But the Amodeo family was forced to shut down its operation in 1980, when an earthquake crushed the distillery that had been a going concern for a century. Thirty years later, Francesco reopened the family business in Washington. He says he's working not just to bring a bit of Italy to the U.S. capital, but also to give the world something else to talk about when they talk about D.C.

"Not just politics or the current topics of the day," he says. "What's D.C. about? Oh, I can get great amaros in this city."

Washington's flourishing foodie scene has been in the news lately, with an even dozen D.C. restaurants being awarded coveted Michelin Guide stars. Amodeo says Americans more generally are setting novel standards for how to drink amaro.

"In Italy ... it's your grandpa and your father's shot," he says. Italians may just drink it at the end of the meal. Americans are using it creatively, in cocktails.

Amaros from all over, and what to make with them

Amodeo and Parsons show off about a dozen different bottles, each with an eye-catching label. They come from here and there on the map — the Italian coast, the Swiss Alps, even Charleston, S.C.

Then Parsons picks up a tiny paper-wrapped bottle called Underberg.

"Underberg is a German digestif that's been around since 1846," he explains. "We're going to take a simple bar straw, stick it in there and take it down in one suck."

(There were productivity-related consequences, it should be noted, to this approach.)

Novices might want to start with Parsons' go-to drink: an amaro and tonic, garnished with lime.

"[That's] what I was drinking all summer for my pre-dinner drink."

For these chillier autumn days, Amodeo has another recipe.

"It's called the Alexis. It's one ounce each of bourbon, Amaro delle Sirene and then Nocino, which is our walnut liqueur."

Mix those three on ice, he says, then either strain it and serve straight up or put it in a highball and serve on the rocks. Either way it goes nicely with an orange twist.

As for the appropriate toast for trying out an amaro cocktail?

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