Burger King's Halloween Slushie Might Turn Your Poop Black and Blue

iStock.com/ilbusca
iStock.com/ilbusca

Of all the spooky events surrounding Halloween, peering into the toilet bowl and noticing that your poop has turned bright blue might be the scariest. This could be your new reality if you slurp down one of Burger King’s seasonal Scary Black Cherry slushies, Women’s Health points out.


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The black-tinted frozen beverage is made from Fanta soda, and presumably, a fair amount of food dye. Ever since its release ahead of the holiday, customers have been complaining that the drink turned their poo “blackish blue,” neon blue, green, or purple. Similar reports surfaced in 2015 after Burger King introduced a Whopper with a black bun that had been flavored with A.1. Steak Sauce. In that case, customers’ “grass green” bowel movements were blamed on food dye in the bun.

“To make poop turn that color green, it would require far more dye than is in the typical type of A.1.," doctor and nutrition counselor Pamela Reilly told USA Today at the time. "My guess is that they're using a concentrated form."

Although the Scary Black Cherry slushie’s ingredients aren’t listed on the fast food chain’s website, food dye is likely the culprit—once again—of customers' colorful poo. Michigan-based gastroenterologist Michael Rice explained to Women’s Health that food dye mixes with the yellow-green pigments in your bile, which is then excreted in your poop. Darker dyes in particular, like blue and purple, tend to yield the most visible changes in stool color. Beets, licorice, tomato soup, Kool-Aid, Jell-O, candy, and tinted icing can all have the same effect.

From a health perspective, there’s not much to fear, though. Aside from giving you a fright after you go number two, the artificial dyes that Burger King uses are within FDA-approved limits. Your poo should go back to its normal hue in no time.

[h/t Women's Health]

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Why Do Prunes Make You Poop?

nata_vkusidey/iStock via Getty Images
nata_vkusidey/iStock via Getty Images

Elsewhere in the world, prunes occupy the head of the table. Here in America, they’re often the butt of jokes. The shiny, sweet dried fruits are both exploited and ridiculed for their laxative properties. But do they really make you poop?

Conventional wisdom and scores of older folks insist that eating prunes will hasten the excretory process. Meanwhile, the European Union says they won’t. In a 2010 ruling, the European Food Safety Authority decreed that it was dishonest to sell prunes as laxatives [PDF]. The ruling, which cited “insufficient evidence” of prunes’ poop-moving properties, was met with incredulity and derision.

One miffed Parliamentarian challenged the ruling. “Most of our constituents do not require a scientific test,” Sir Graham Watson said. Watson then challenged the commissioner of health and consumer policy to a prune-eating contest, inviting the man to “see for himself.”

There actually is a good amount of scientific evidence to prove the power of prunes. On his Compound Chemistry blog, chemist Andy Brunning noted that studies in 2008 and 2011 concluded that prunes do indeed make effective laxatives.

Like many fruits, prunes are high in insoluble fiber, which adds bulk to food in the process of digestion while also helping it pass through the system faster. Prunes also contain sorbitol, a sugar alcohol that's used to sweeten things like chewing gum. It appears naturally in prunes, though it's often used as an artificial sweetener in "sugar free" chewing gum. Sorbitol is a laxative, which is why you should be mindful of how much sugar-free gum you chew.

The sorbitol isn’t working alone though, Brunning says. Prunes are naturally laced with neochlorogenic and chlorogenic acids—the same chemicals that can help send you to the bathroom after finishing your morning coffee.

So yes, prunes can ease the passage of certain personal parcels. But they’re also delicious—a fact often overshadowed by their functionality. That’s why, in 2000, the prune lobby launched a massive rebranding effort. Hit up the dried-fruit section of your supermarket and you will likely find “dried plums" instead of prunes.

“Ninety percent of consumers told us that they'd be more likely to enjoy the fruit if it were called a dried plum instead of a prune,” the newly renamed California Dried Plum Board said in a press release titled “You Won’t Have Prunes to Kick Around Anymore.”

Under any name, "dried plums" still have the power to move you—no matter what the European Union says.

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