In the U.S., "you've got the whole cocktail and mixology culture coming into play now," says Datamonitor's Tom Vierhile.

Shandies, he notes, have always been more popular in summertime, when beer drinkers are looking for a lighter brew to help chase off the heat. And younger drinkers, he adds, tend to favor a sweeter alcoholic beverage.

But globally, Vierhile says there's another fundamental reason why shandy is growing in popularity: Because shandy is beer mixed with another, usually non-alcoholic drink, it's often half as alcoholic as the same volume of a regular beer.

And less is better, he says, in a world where governments are tightening laws around drinking and driving, reducing the legal limits for how high a drivers' blood alcohol content can be before they're breaking the law.

"Depending on the local laws, you may be able to drink a shandy and still be within the legal limit for driving," he notes. "If you're in a place like Germany, with a limit of .05 percent [blood alcohol concentration], which is lower than the U.S.'s at .08 [percent], you could still drink a shandy, legally," and then get behind the wheel.

That's good news for U.S. beer drinkers, considering that the National Transportation Safety Board recently backed a proposal to lower the legal blood-alcohol threshold in the U.S. to match Germany's .05 percent.

Funny enough, its lower alcoholic punch is also why shandy was eagerly embraced by 19th-century England, says beer historian Ron Pattinson.

"People outdoors in the summertime," he says, "wanted a refreshing drink with less alcohol than full-strength beer."

A shandy in the summertime. A shandy in the summertime. Photo: Holly E. Clark / flickr

The drink was originally known as "Rich Man's Shandy Gaff," a mixture of champagne and ale, he says. The 99 percenters who didn't have the money to shell out for bubbly substituted ginger beer or lemonade, he says.

Drinking shandies was practically patriotic in 19th-century Britain. As beer historian Martyn Cornell cites, an 1866 British parliamentary report on the mortality of troops in China noted with approval:

"Soldiers drank a great deal of iced ginger beer with porter or ale mixed with it, and at the time, there was very little drunkenness among the men."

(Government officials were apparently less enthused a few years ago, when they had to officially ban police officers in Leicestershire, England, from drinking Shandy Bass – which contains 0.5 percent alcohol - while on duty.)

While shandies are a traditional British drink, they're not exclusively so. For centuries, from Italy to Japan, people have imbibed shandies with slight variations. (Germany's version, called the radler, is also well-known.)

This is not even shandy's first dalliance with American beer lovers: A drink called Lemon and Lager was introduced in the 1980s, but was a flop, Vierhile recalls.

"It may have been," he says, "ahead of its time."

Copyright 2013 NPR.

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