Booze, Stews, and Green No. 2s. It’s St. Patrick’s Day at uBiome!

The man who dyed his poop green. The how, if not the why.

Some may greet you with a “Top o’ the Morning” today, but given our professional interest in fecal matter, you may not be too surprised to hear us opting instead for a “Bottom o’ the Morning.”

Apologies if you’re just breakfasting on a couple of celebratory Irish sausages.

Anyway, just as they have every year since 1961, members of the Chicago Journeymen Plumbers Union have been pouring dye into the waters of the Chicago River to turn them fluorescent green for St. Patrick’s Day.

This got us wondering how one might go about dying one’s poop green to mark this auspicious day, which inevitably resulted in us thinking about other colors, too.

But given that today is all about St. Paddy, let’s start by investigating the possibilities of you squeezing out a Shamrock Green No. 2 in the next 24 hours.

What would this take?

Well, thanks to a fascinating study carried out in 1996 by a student identified only as Dave J, who was attending a small liberal arts college in northern Vermont, it would take a prodigious amount (6 liters to be exact) of a particular drink.

Purplesaurus Rex Kool-Aid.

You see, one evening Dave J knocked back an impressive 1.6 gallons of the purple (yes, purple) drink, then was pretty shocked to find himself producing bright green poop the next morning.

Sufficiently shocked, in fact, to proudly invite his housemates into the bathroom to admire his magnificent specimens.

Those 90s students, eh?

Anyway, Dave J was intrigued enough to run a second experiment with 25 fellow students.

Each was asked to consume a total of 6 liters of fluid, made up of gradually increasing ratios of Purplesaurus Rex Kool-Aid to water.

Participants were then requested to refrain from moving their bowels for six hours, before providing Dave J with a specimen.

Awash (well, hopefully not literally) in poop samples, Dave was able to conclude that the more of the purple stuff you knocked back, the greener your poop would be.

But why green, rather than purple?

Well, at least back in 1996, the purple coloring of this flavor of Kool-Aid was the result of two of its ingredients: FDA Blue #5, and Dye-Lake Red.

Blue #5, a common food coloring, is also known as “Brilliant Blue,” and it’s a byproduct of petroleum.

We know, right? Yum.

Considered harmless, it’s poorly-digested by the gastrointestinal tract, to the extent that 95% of what enters the mouth makes it all the way through to the rear end.

As it passes through the gut, it combines with bile – yellowy stuff that comes from the liver – and, hey presto, you mix blue and yellow to get green.

Oh really? O’Reilly, more like.

Of course, we’re generally used to poop being brown, largely the result of old red blood cells from the liver.

They end up in an orange-brown substance called bilirubin, then mix with the aforementioned yellowish bile, to make a brown color.

Just like combining paints, really.

Poop sometimes changes color because of health-related factors, and experts from the Mayo Clinic warn us to take notice, particularly if stools appear black or red, as this may be caused by internal bleeding.

However, it’s also possible for color changes to be the result of other dietary modification.

For example, some people eating newly-released Peeps-flavored Oreos are apparently laying spectacular magenta-hued poop.

Over the years, a couple of diet-induced color-changing crap cases have even made it into seriously respectable scientific journal articles.

For example, in 1971 General Mills introduced a range of monster cereals, including Franken Berry.

After eating a couple of bowls of this pink cereal, a 12-year-old boy in Maryland ended up in hospital after producing stools that were described as, “somewhat loose, and looking like strawberry ice cream.”

Thankfully, his condition cleared up after a few days in hospital, and was proved to be caused by the cereal when the young patient was given four bowls of it, only for his poop to turn back into, yup, strawberry ice cream again.

Reporting on the case, the February 1972 issue of the journal Pediatrics used the term “Franken Berry Stool.”

15 years later, the same journal carried an article about a five-year-old boy who was rushed to the University of Virginia Children’s Medical Center, after producing red-orange poop, potentially a sign of blood in the stool.

After extensive evaluation by physicians, the boy finally confessed to having eaten a whole box of Nerds cereal, prompting his mother to offer a diagnosis which outdid “Franken Berry Stool,” and once again made its way into the scientific literature.

Her apt description?

“Nerds turds.”


Food coloring/poop-modifying cases still crop up from time to time.

Back in 2012, for example, kids were turning up in emergency rooms with scarlet stools that simply turned out to be the result of eating substantial amounts of Flamin’ Hot Cheetos.

Mind you, the spiciness of this particular snack suggests they were fortunate to have merely suffered from red poop, rather than a ring of fire.

If your celebrations tonight involve a glass or five of green beer to wash down your Irish stew, you’re probably not going to experience emerald excrement tomorrow morning, as the ale-formula simply involves adding a couple of drops of green food coloring to light-colored beers like Pilsner or IPA.

If, on the other hand, your celebrations involve knocking back over 12 pints of Purplesaurus Rex Kool-Aid, well, you only have yourself to blame.

Purplesaurus Rex?

Frankly, that sounds more like Barney than blarney to us.

Happy St. Patrick’s Day.

More reading

Benign Red Pigmentation of Stool Resulting from Food Coloring in a New Breakfast Cereal (The Franken Berry Stool)

Chicago has turned its entire river bright green for St Patrick’s Day

Green Poop: The Implications Of Food Dye On Poop Color

Nerds Cereal and Red Stools

Peeps Oreos & 7 Other Things That Turn Your Poop Strange Colors

Stool color: When to worry

The phrase “Franken Berry Stool” appeared in a serious medical journal

Why Is Poop Brown?