Scotland’s other national drink is bright orange and a foolproof hangover cure. Probably.

As a Scottish university graduate, I can reliably inform you that Irn-Bru is the world’s best hangover cure. Probably. I’ll confess I didn’t really know what the nuclear-orange soft drink was before moving to Glasgow, but it wasn’t long into fresher’s week that I found out.

From what I recall, I was first presented with a glass in the communal kitchen of my Murano Street residence hallnear the pub where Begbie chucked a pint glass over a balcony in the movie Trainspotting. (Though the movie was set in Edinburgh, most scenes were filmed in Glasgow.) I think it was the morning after a traffic-light party (where guests advertise their romantic availability with red, green, or amber stickers) at one of the student union bars. It was the late 1990s, after all. I’ve had a bit of a nostalgic thing for it ever since. Irn-Bru reminds me of Britpop’s sunset years, the Cool Britannia era of the 1990s, the optimism of Tony Blair’s Britain, and just generally having the time of my life.

To the uninitiated, Irn-Bru is widely known as the “other” Scottish national drink, besides whisky. The formula is such a closely guarded secret that only three people know the recipe and they’re apparently not allowed to travel together on planes.

Irn-Bru is so popular that, according to legend, it’s the number-one soft drink in Scotland, outselling even Coca-Cola. The truth is, no-one really knows because market data doesn’t include local shop sales. But AG Barr, the company that makes it, does know that it sells 20 cans of Irn-Bru every second which is, quite frankly, a lot. Another legend has it that Irn-Bru is the toughest stain to get out of carpetsharder to remove than even red wine, curry, and permanent marker (Sharpies). This one seems to be true.

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So what does it taste like? One friend describes it as sunburnt orangeade, while another says it’s like combination of a world-renowned energy drink and bubblegum. My mother-in-law claims it tastes like barley sugar.

To me, it is somewhat sweeter, but less sharp than Coke. It is also not quite as fizzy and is refreshing. Somehow it seems more appropriate to serve at room temperature, rather than ice coldalthough I’m sure there are folks who’d disagree. Perhaps I feel that because I associate it with the mild, and often somewhat drizzly, Scottish weather, which means a cooling refreshment is often not needed.

Irn-Bru was born in 1901 when steel workers rebuilding Glasgow Central Station were drinking too much beer to quench their thirst. So local soft drink-maker AG Barr developed a tonic-like drink, with caffeine and sugar, to help them get through the day.

Iron Brew, as it was known then, so became long associated getting Scots through tough times. This reputation was sealed in a highly-successful advertising campaign from the 1970s onwards which branded it as “Your other national drinkmade in Scotland from girders” [steel beams], jokingly referring to its orange colour as “rust”.

The name change came in 1947, when government regulations proposed that brand names should be “literally true” and while it did contain iron, and still does, it wasn’t brewed. So the drink was phonetically renamed Irn-Bru.

AG Barr’s bright-orange and blue branded 750ml glass bottles of Irn-Bru are now something of modern Scottish folklore. While you can buy it in various different forms – large and small plastic bottles, and cansaficionados will tell you that glass is best.

Part of the reason Irn-Bru became so ingrained in Scottish culture, and beyond, is down to the massive success of their often controversial ad campaigns. One billboard featured a cow next to the phrase “When I’m a burger, I want to be washed down with Irn-Bru”, while a particularly memorable TV advert saw a granny on a mobility scooter ram-raiding a supermarket for her weekly stock of the orange nectar.

And for many Scots, it’s not Christmas until the Irn-Bru ad—a version of Raymond Briggs’s 1982 animated film The Snowmanis shown on TV. Set to a revised version of Howard Blake tune “Walking in the Air,” the ad features the young boy and the Snowman flying over famous sights in Scotland while brandishing a can of Irn-Bru.

But what about its miracle properties as a hangover cure? Well, many Scots will tell you that Irn-Bru is most potent when consumed from a glass bottle, although they’re only available in Scotland and England; elsewhere, you’ll probably have to stick with plastic bottles or cans. Some swear it works best if you open a bottle before heading out for the night, let it go flat, and then swig it all when you get in. Others just drink it the morning after. I’ll confess that I still occasionally swipe a can of my husband’s stash after a night on the tiles, and I’m 37.

Photo by: Weho / Shutterstock.com

This reputation as a hangover prophylactic was somewhat threatened earlier this year when AG Barr announced it was massively reducing Irn-Bru’s sugar contentfrom about 10 mg per 100 ml to just below 5 mgin response to the newly-introduced sugar tax. (Sugar is supposed to help rehydrate the body after a night’s drinking.)

The news triggered a mass stockpiling of the orange fizzy drink. Full-sugar versions are still being sold on eBay. People in the Scottish Bordersthe region just south of Edinburgh and just north of Scotland’s border with Englandwere said to be traveling to England to buy Irn-Bru, where it was less popular, while some canny shopkeepers stockpiled stashes of cans for months before selling them.

AG Barr insists it worked hard to maintain Irn-Bru’s same unique taste with the reduced-sugar versions. (A sugar-free version has been around since 2011.) The jury may be out on that, depending on who you speak to, but it’s undeniable that its position in the Scottish cultural canon remains unchanged.

Also manufactured in Russia under licence, Irn-Bru’s distinctive blue-and-orange packaging can be found in shops across the world, from Europe to Asia to Australasia. And for those who find it, it will always be a taste of home.