Green Poop: The Implications Of Food Dye On Poop Color

l 100+ pointsm 1+ points - Newb

Editor's note: here's the short answer -- blue food coloring turns your poop green. Keep reading to find out more, and then peruse the many, many comments for corroboration.

Since my freshman year in college (a small liberal arts college in
northern Vermont), I've been fascinated with the correlation between the ingestion of
food-coloring and the color of the poop produced. Lest you think I'm fabricating, here's the background:

The year was 1996. I was a biochem major at St. Michael's College in Winooski, Vermont.
I had consumed copious quantities of Purplesaurus Rex
Kool-aid in a one night time frame. A few hours later, I pooped. It was
green. Bright green. I was fascinated, and called as many of my
floor-mates as would come into the stall to marvel at the miracle of the
"not brown, not bloody shit".

I was a bit of a celeb for a while, until others replicated my
"experiment". Similar results ensued, with me being notified of each event
via e-mail. So, a craze started.

As the progenitor of the new species of poo, I was caught in the middle. Research spread far and wide; of
a campus of 2700 students, I was receiving up to 45 e-mails a day from

Anyway, enough drivel. Here's the science:

The dye used in purplesaurus Rex is FDA Blue #5, and dye-lake
red. Turns out that when metabolized in sufficient quantity, the blue dye combines
with bile, and forms a brilliant green. The red, absorbing at a 595nm
spectrum, is harmlessly eliminated.

What matters is quantity. I consumed 6
liters of the Kool-aid in the night in question (sans alcohol, that comes
later). I set up a study in the dorm, with people consuming anywhere from
(1) 250mL glass of the stuff (approximately (1) 8oz glass) to the maximum tested
so far, 6L. The experiment was structured on a single-blind study (won't get FDA
approval, but sufficient), with only myself knowing what each was consuming.

How did the experiment come into being, you might ask? Well, I campaigned for 24 "volunteers"
(the first consuming 1 glass, the last consuming 24 glasses). How did they
not know what they were drinking? Well, since it was only single-blind,
they essentially did -- though all were required to drink 6L of fluid total,
and ordered not to defecate at all in the 6 hours of the experiment.

Example: Subject 1 received 250mL of the subjected test substance, and
5.75L of water. Subject 2 received 500mL of the stuff and 5.5L of water.

Everyone was agreeable at first, but soon dissention reigned prime. But order
was maintained. After 6 hours, orders were given to poop, supervised (more or less).
Since I had unrestricted access to the chem and bio labs, samples of each
"extrusion" were taken, in the amount of 2g.

The results were heartening. I plan on getting a PhD (which, in this instance would probably mean, "PUSH
HARDER, DUMMY!") on this someday, so I won't post my final data, just enough
to give an idea:

  • Subject 1: 250mL Purplesaurus Rex with 5750mL water:

    Stool, firm and brown. Spectrophotometer reading: normal.

  • Subject 12: 3000mL Purplesaurus Rex with 3000mL water:

    Stool, firm(ish) and green(ish). Spec reading 550nm (definitely Green...just not GREEN)
  • Subject 24: 6000mL Purplesaurus Rex with 0mL water:

    Stool, Firm(ish) and
    Green, resplendent of original test subject (me). Spec reading, 535nm. Definition of GREEN confirmed.

  • Further experiments considered fruit punch (mostly synthetic, only 2.5%
    fruit juice), Hi-C of various persuasions, and various and sundry other
    store-bought concoctions.

    If you're interested in my results, let me know...I'll gladly share them for
    the good of society.

    -- Dave J

    On May 27 2003, received this email. Dave J, the author of the above piece, was so happy that he wanted this added to his story as proof that writing for PoopReport can improve people's lives.

    dear poopreport,

    i know you may find this hard to believe, but you just eased my mind tremendously about our daughter's "poop situation." beginning yesterday about 5p.m. our daughter began having bright green dirty diapers. she has had four in a 24 hour period and i (being an over paranoid mom) have contacted everyone i know, including our pediatrician, and no one had any answers other than it will probably go away. that response just does not cut it with me. i had to have answers. i have been on-line non-stop trying to dig up a possible answer. i told our doctor that the only new food or drink she had consumed was "purple kool-aid" and lots of it. he told me that purple kool aid would not produce green stool. after reading your article i realize it can. thank you soooo much. after hours of searching and worrying, i am off to bed.

    -- grateful mom

    1629 Comments on "Green Poop: The Implications Of Food Dye On Poop Color"

    Green Poop's picture

    Lucky Charms cereal = olive/spinach green poop.

    Yellow dye #5 & #6, Blue #1 and Red #40. There must be a buttload (so to speak) of the first three.

    Any food coloring that survives passage through the stomach and intestines is a bit too scary IMO. This is the last box of Lucky Charms I ever buy.

    Anthony's picture

    I'm a security officer working night shifts, hence, I stock up on plenty of energy related drinks etc. Last night I decided to drink approximately 5 litres of purple Gatorade. I went to have a dump this morning and noticed I was excreting 'green stools'!. Amazingly one 'stool' was half brown-half green! I'm glad I found your website, it ended my panic, I was about to run to the emergency room! hehehe

    Good website mate!

    Imma Gone Shitz's picture

    Here's another "me too!" story. I have been eating Capn Crunch Berries cereal the past few days and I noticed today a green dookie floating around in the bowl. I had a good laugh and figured it was no big deal. A couple of turds later when it was still green I started to freak out. I thought maybe a toilet snake crawled into my bum while I was wasted one night and taking a crap. Now, the toilet snake was somehow making my dookie green! What was I gonna do? I had the water hose out and in position when common sense kicked in and I did a search on yahoo. Needless to say, my ass thanks you as I can now return the pressure washer I just bought. :)

    pontiff holy shit's picture

    i have crapped two colors before. Green (because of copious amounts of grape kool-aid) and orange (i like the fishes cause they're so delicous!). thats right gold fish cheese crackers. i once snack on WAYYYY more than the recommended daily allowance and my crap came out orange. boy, was that crazy! just today i had a green one and icame here to find out why. and know i know.... grape kool-aid.

    kristin's picture

    I woke up today hungover as hell and couldn't stop pooping electric green. I couldnt figure out why until I came to this website and saw the thing about koolaid. I was drinking bright blue drinks last night that had koolaid in them. Thanks!!

    Kris T.'s picture

    WOOOOOOOOOW!!!!!!!!!! I have had a steady diet of creatine for about a week now, currently i am drinking "grape kool-aid" for the simple carbs to digest my creatine better, like two days ago my poop was green, and because creaine can cause liver and kindney problems i thought that my body was no longer producing bile!!! Thank you soo much for clearing my question up!!

    Jena's picture

    Thank you for sharing your poop stories! Without your
    research we would all be running to the emergency room! This morning I had the green poop and was very
    scared! I consulted 4 medical books - none of which EVEN MENTION this
    phenomenom! I hit on your
    site and immediately figured out what I had eaten! Yesterday I made a big
    chocolate chip cookie. I used BLACK CAKE MATE FROSTING to make the lettering. After reading your poop stories I immediately retrieved the
    tube. It contains Red 40,
    BluE 1, and Yellow 5.
    guess what you get when you
    mix those colors! GREEN!

    Simone's picture

    Can't tell you how much you helped ONE MORE WORRIED MOM! My daughter had green poops for 2 days now. I collected some (the good biologist that I am), and put in our frig. Had to disguise it so it would not detract from anyone's appetite when staring at the open frig. I was making the doctor appt. tomorrow. Then did a search. After several hefty medical sites, I found you! She had a snowcone with Bubble gum and Grape mixed. And it was a slurpy one! Must be the Blue #5. QUESTION: how long did the green stool effect last?

    Appreciated so can sleep restfully....WAIT, GOTTA GO GET THAT JAR OUT OF THE FRIG!!!

    Simone's picture

    PS: DAVE, how's the Ph.D. coming?

    gangsta guy's picture

    i drank a shake today made from an ice cream called "cookie monster" a blue ice cream with cookie chunks in my suprise my shit was bright green? wut the fuck?

    Summer's picture

    Just a year ago I had the stomach flu and bad diareah. Well, one of the times I used the pot I dared to peek in and it had this orange 'glow' and looked like a lava lamp. I wasn't even eating at the time. Just downing Pepto! Now I've had Pepto turn my shit pitch black but never lava lamp orange. Has anyone ever had that happened?

    shorty_shit_stain's picture

    phew!!!! thought i had an S.T.D or somethin.

    tpg's picture

    WOW WOW WOW!!! Now I can finally flush. I swore I would need a samlpe for the lab or something. That crayola green stuff scared the crap out of me, no pun intended.
    Now I know it was the 3 bowels of CRUNCH BERRIES that I had for din din last night. Thanks.
    They could at least put WARNING:::::THIS Will TURN STOOL bright *## GREEN!!!!!!!!!

    Lb's picture

    I started experiencing green poop recently and did not know why. I was scared. But I know it was probably the blue powerade I have been drinking~~ Thanks alot!!

    maa's picture

    Thanks a lot

    Rick's picture
    m 1+ points - Newb

    Yo, how u doin? Ive been drinking this blue cocktail a lot yesterday, and today I had to go and drown a thurd in the toilet....I saw green poo all over the place and thought.......shit!

    But now, I see that consuming blue, or other things make my shit so nice! AINT THAT COOL!? *grabs 2 bottles of blue cura

    Denise's picture

    Lucky Charms (with NEW great green clover marshmallows) made my poop green.

    Beazalbob's picture

    Wow it's the Fruit Loops!!!! Been shittin green for 3 weeks was wondering why thanks for the info now I know I am not going to die form this lol

    Elaine's picture

    Why don't pediatricians know more about this? I actually paged ours when my son pooped Kelly Green! He had had both a slurpie and Capn Crunch with crunch berries the day before this happened. I had actually eaten the same things without a problem but I guess his system is different from mine or more vulnerable. Scared the heck out of me because he had scarlet fever two weeks ago and I was already on the lookout for bloody urine, which is a serious complication of the fever. Instead I got THIS technicolor surprise.
    Thanks to all for being so honest! I feel a lot more relaxed about it and I can stop quizzing my embarrassed 9-yr old about his movements! Poor kid will need therapy soon!

    Q's picture

    didnt know what was happening with my digestive system till i read this, however in my instance kool aid is not the cause but a multi- flavored ice cream. it consisted of bright red, blue and yellow colors. maybe you should look into it, the ice cream is one of those cheap ones that come in a tub.

    R L Johnson's picture

    Got mix of regular color animal crackers also with RED and BLUE (4th of July Mix). 1 day later BRIGHT GREEN stool just like Kool-Aid. I didn't think that that could happen but....

    Jim's picture

    Hmm, I think I might be defying your experimental rules for green crap. Over the past 2 days I have eaten toast, cheese, bbq beef with rice, 2 bananas, one can of spaghetti, and I have had one vitamin tablet. I had about 1.5 litres of water each day. Today, my crap was a definite green colour and my piss was a florecent yellow (and I really mean florecent, it almost looked radioactive). My stomach hurts a bit but I hope I will get over it... wish me luck!

    wendy's picture

    am trying to figure why our rooster's poop is a bright, almost neon green.some one said grass, but they eat it all the time and it wasn't green like THIS! maybe dark green or just gryish brown. this site gave me hope except that my roos don't drink koolaid. could they have ingested the dye some other way, like through a chemical possibly?

    justin brain's picture

    If you drink nothing but fierce grape gatorade`for 3 days your poop will also turn green

    lynn's picture

    i started to drink this organic green tea, and my poop has become greeny ever since...

    Michael's picture

    Oh man, this is freaking hilariious! I've been having bright green turds for the past week and decided to investigate after getting a little nervous. After reading all of these posts, I now realize it is because of the new cereal i've been eating a lot of lately: Cap'n Crunch Crunch Berries!

    dookie dog's picture

    I ate a massive amount of beets on St. Patricks day, the next couple of days my shit was blood red I freaked a friend of mine saw it and thought my liver burst I was rushed to the hospital, I don't eat beets anymore.

    gypsy's picture

    Like a previous concerned mother, I was very disturbed that my daughters poop was bright green. So, after reading your site and examining her recent diet. I think I may have found the culprit. Grape soda. It is the generic Wal-Mart brand equivalent to Nehi.It contains Blue #1 and Red # 40.
    My only concern is that she threw up two nights before the Glowing green poop incident and her vomit was also green. I assumed it was bile. I have yet to find the name for the childhood intestinal illness for green or blue poop. She has had blue poop in the past I assumed food coloring but couldn't find anything blue in her diet. So what turns poop blue?

    not chocolate's picture

    I wish I had to poop every day. But I don't. It's every other day. Is that normal. Oh and I find it strange that people indulge in pornography featuring men and women with dookie fetishes. . ughhh how gross

    Audra's picture

    I can't figure out why my poop is neon green. Not just neon... NEON. All I ate were some nutter butters and a LOT of water. I'm not really concerned... just interested.

    Tim's picture
    m 1+ points - Newb

    I drank 8 sodas last nite and crapped green this morning after a stomache ache. Its actually quite cool!

    Dean's picture

    I bought a box of 150 FlavorIce Icepops and munched on about 50 of them within a couple of hours last night. All colors, red, green, yellow, blue, ect. I shit just now, and it was glowing. Haha, not really glowing, but Damn, it was green! I'm gunna go eat the rest of them now.

    SL's picture

    My poo has been green for the past two months. It just changed all of a sudden and now it's constant. Too embarrassed to see a doctor but I'm worried. Help

    bob flanmou's picture

    i have eat 2 bag of blue cotton candy, i was worried but i find your site and now im reassured

    greeeeeeeeeeeeen's picture

    for my 17th b-day back in january, i had a cake with green frosting. The next day, my shit was so green, it wasnt funny. I wonder if it had been glow in the dark, then my "productions" would have been as such.

    rlerb's picture

    pound of bing cherries = neon green poop

    emt_poo's picture

    blue icing from walmart cakes will also make your poo GREEn

    Greenmy's picture

    For the past few week after eating some cereal amazing "shit" happens: Not only my turds is green but the water is green also. The toilet and everthing is green! I usally take a while to force out the poops and ever-since I poop green, it only takes like 20 sec.

    chrissy's picture

    Oh my gosh! how helpful. I thought I was totally sick or something. I have an infant that I now it's normal for her to poop green, but when I started doing it today. I have been freaking out. I drank a lot of that minute maid rasberry lemonade yesteday and added sugar to it. I must have had 3 to 4 glasses yesterday and my stomach wasn't feel too well either. Not to be gross but earlier to day when I pooped it had a bright green lines down it and just now it was just bright green, I thought it may have been from metabolife, but it never did it before. Anyways, thanks a bunch.

    holy hell!'s picture

    Holy shit! I thought I was sick when my craps were green. vomit green. ew. Anyways, try drinking 12 cups of Cool Blue coloured Raspberry Lemonade Kool-aid, or Cool Blue coloured Berry Punch Kool-aid. Sick effects.

    kaka kate's picture

    any studies done on lucky charms? i think those little green clovers got to my bowels.

    sharpie's picture

    You put my mind to rest, I thought I could have cancer with the green colored shiznit laying on the bottom of the bowel, green liquid all around. I've been drinking alot of Mountain Dew lately, this must be the culprit.

    icky's picture

    THANK YOU! I felt weird doing an internet search called "green feces"..... but the minute my boyfriend left my apartment, I ran right to the computer. There definitely wasn't going to be any hanky-panky tonight after what happened since I drank 2 gallons of grape Kool-aid in the last 2 days! I was scared something was wrong, couldn't discuss it with him, and counted down the minutes until he left so I could check this out- so thanks for the site and info!

    Eric's picture
    m 1+ points - Newb

    You can poop blue if you consume enough (a *lot*) blue food coloring to overpower the rather strong yellow pigment that's a normal part of your poop (the usual brown is really mostly yellow with a little bit of green and red; all three colors come from various breakdown products of a bile pigment).

    By the way, the fact that food coloring goes in one end and comes out the other implies that it's simply inert as far as your body is concerned; it doesn't get absorbed into the bloodstream (physiologically speaking, something that's present in your stomach/intestinal/rectum contents but not in your bloodstream is *outside* your body). That's why food coloring doesn't, for example, change the color of your pee (the red natural pigment in beets *can* change the color of your pee as well as your poop because some of it gets absorbed). In that respect, it's much like fiber.

    Incidentally, there are, as far as I know, *no* diseases that cause green or blue poop without any other noticeable gastrointestinal symptoms. In particular, colon cancer usual results in *no* visible changes in poop color, or, for that matter, any other symptoms unless it's quite advanced. That's why it's considered a "silent killer" and why screening is important for people who are susceptible (over 50, family history, etc.). The only poop colors that could indicate immediate danger are white (unless you've swallowed barium for a GI X-ray, white indicates a lack of bile pigments which suggests a liver problem) or tarry black (unless you've been taking Pepto-Bismol, this can indicate the presence of partially digested blood, suggesting bleeding in the stomach or small intestine; this symptom is called "melena" and the poop so affected usually stinks much worse than usual).

    Sherman's picture

    we went to a chinese restaurant recently and my brother took a bunch of shots of soy sauce. he shat straight soy sauce for two days. worst poops of his life he says.

    Mo's picture

    I was getting food the other night and saw a special for this Captn' Crunch, it turns the milk blue or what ever.. so i got 2 boxes of it. I've had like 3 bolws since then. And today.. i get home from work, and go potty... and when i wiped i notice it's green... No biggy it's been green before. Then when i got up i see that it's green and red!!!... it was like when you squish differnt colors of playdoh together, they don't mix, just kinda inner-twine... it freaked me out!!.. i was like "HOLY TWO-TONE CRAP!... i've never seen shit it like that before. I called my roomate who was at work and i told her of my two-toned pooh, and she was left speechless. she was no help. so then i jumped on line and a friend told me of this site... all these post have made me feel a lot better about my two-tone, christmas like pooh... although now, i may have to feed the cereal to this once chick at work who i can't stand and wait for the results! MWUAHAHAHAHAHAHAHA!

    G's picture

    thank you so much for your site!! I couldnt figure out why i was shitting bright lime green until i typed green poop into google and this site came up! For 2 days ive been crapping green, and i thought it was because i had some kind of deathly intestinal problem, until i read your research! Over the weekend i ate a huge amount of the Blue ice cream at TCBY with poprocks in it and then on Tuesday i went back for more, only this time it was the Arthur (yes, the childrens book character) ice cream that had every single color of the rainbow in it!! I feel so much better knowing i can enjoy that ice cream (it is SO good!) and feel okay about my crap being flourescent! Oh and FYI, if you want bright blue poop, drink a 6 pack of the bright blue wine coolers! That made for some fun senior week times! Happy pooping!

    Christy's picture

    Wow I feel better now. Glad to know I was not the only one crazy enough to search the web for green poo info. Its got to be the Lucky Charms cereal for me. They added green clover to the mix and I have had a bowl every day for the past week. Keep up the good work!

    courtney's picture

    why is it always green

    Mike's picture
    m 1+ points - Newb

    Whew,. thanks for posting this, I found "greenish" poop, and got scared,
    now I know all is well. Drank grape Gatorade last night.
    Thank you again.

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