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"

    BrownStuff's picture

    Does anyone know if Lemonaid will cause shit to be green? I started to have green shit about ate(sorry!!) ago and then too weeks ago my wife had green shit, could't finger out what was going on!! Then twoday my little girl tells me that she two had green shit!! So what is going on?? I enjoy drinking Lemonaid, wife enjoys drinking crystal light tea and my little girl enjoys different kool-aid drinks!! any suggestions??

    Dee's picture
    m 1+ points - Newb


    cynthia's picture

    my son 12 years old had pains in his stomach and diarrhea he ate some pixy sticks yesterday and had green poop. Should i be worried!

    Jon's picture
    m 1+ points - Newb

    thank i had no idea grape kool aid or grape beverages cause green feces,,,thank u so much for yals dedicated experiments and ur help god bless all of u,,, i thought something was terrible wrong with me

    Turdtard's picture

    Whew... Several people close by in my family have had bleeding intestines in the past. Though my poop wasn't bloody, I thought that when it turned out green that it was somehow related. I never said a word to anyone, pushing the thought deep within my mind trying to pretend it wasn't there. I was afraid that i would just deny it until i grew old and bleed out my butt and died that way. Now I have been edjimafied, and know that it is in no relation.

    Poop Concerned's picture

    Hi, I havent been drinking kool aid I actually dont like the taste. Can you tell me how I might be producing green poop. Thanks so much.

    dAnkEy's picture

    Not too long ago i sat on the toilet, dropped a single turd, wiped my ass, got up, stared in the porcelain queen, and there was this bright, glowing green shit. Perpetrator - grape koolaid mixed with a melted down black cherry slushee. thats come cool shit!

    saber's picture

    Ha ha Ok, I drank a blue colored Gatoraide for days while working outside. My poop was turning out green. Although I stopped eating vegtables in order to check it was still coming out green I did a search and bada-boom-bada-bing, I found this site and my answer. It is funny to know that i am not the only one who is noticing the color of my poop....lmao Thanks

    Mikus's picture

    I went Blueberry picking w/ my g/f Friday. Since then, it's been blueberry pancakes, blueberry pie, blueberry muffins, etc...don't get me wrong, I love blueberries, especially when they're sweet and super tart at the same time. Well, since Saturday morning I've been dropping green toilet bombs. I think it might be ANYTHING with strong coloring(maybe just strong blue/purple/etc). PLUS I just moved to New Jersey. It could be either one, or both... I dunno...

    RyKo's picture

    Did you know you're the top ranking at for "green poop"? Well you are. Green poop today, thought it was odd. Off to the 'net I go. And here I am. What did I have to drink yesterday? A couple of glasses of some blue (Blue #5?) Kool-aid.

    in persuit of the truth's picture

    Wow this is entertainment!!! All I did was type in "kool-aid playdoh" and found this site towards the bottom! Happy deposits to all!!!

    denise's picture

    hi, im having black poos but a dunt no y can u tel me?

    Kathy P.'s picture

    sick to say...I'm oddly enlightened by the whole deal! ha ha ha ha

    james's picture

    I pooped green after eating raspberry and blackberry gum drops. I couldn't believe the color in the bowl. Today the stools were half brown and half green, maybe normal tomorrow? dolorsed andd

    David's picture
    m 1+ points - Newb

    Dee mentioned how s/he loves the Internet, me too, thanks Al Gore. :) Like many of the writers above I started to get very nervous when I saw that bright green stool today--first time I ever remember seeing one. I could not think of what I had eaten different. Then I thought, I'm sure the Internet will have the answer and this site did. Turns out at an office birthday party two days ago I had eaten a cupcake with blue frosting on it. So there you go.

    pooperazzi's picture

    Well apparently the phenominia is not limited to kool-aid. Jello will do the same thing or so I just discovered. At least I hope that is the case. Its good that his web link pops (poops?) out first when one does a google search. I was getting a bit worried there. Thanks.

    ROFLMAO's picture

    Chinese food did it you me. Well... not quite chinese, but it was teriyaki in a chinese restaurant. I belive that would be the culprit. Since it was that Reddish color. Either that or the Sweet and Sour Sauce... Word.

    Irma Morgenroth's picture

    I am so glad I found your site.
    I was so shocked when I saw green stool,the only thing that I eat differend was bean sprouts.But now I feel better, since I read all the comments.

    Chris's picture
    m 1+ points - Newb

    Blue powerade/Gatorade also does the green poop trick. I've been drinking tons and my poops been green for about a week.

    george's picture

    i have had green shit for 3 days now and i dont no y it is a sort of army getting lighter each day waht can i do?

    shat shall be spoken's picture

    does skittles turn ur poop green.......or blue corn chips

    Mom of 4's picture

    I cannot believe that I am actually typing this in here. But, this morning my 1 year old had the neon green "problem" in his diaper. NO OTHER sight but this one helped me. See, he had a slush at the beach yesterday. Blue and red mixed together. Well... we all know what color that makes.... purple.... Purple turning into green..... Wow. Thanks for the research.

    mae's picture

    Is kool aid the only thing that can change poop green? Is this healthy, has anyone asked?

    Ms. Lesa's picture

    I am so amazed by how long people have been posting messages on this site. This is crazy! But I too have a green poo story similar to those already posted. I just got back from a summer class in West Africa a few weeks ago and ever since I returned I've been pooping green. Now I'm sure you can imagine my distress. I'm thinking I have malaria or typhoid fever or some crazy disease like that. So today I finally get on the computer, go to ask and type "why is my poop green?" Then BAM!!! This website pops up and makes everything clear! Since I've been back I've been eating like 5 bowls of Capn' Cruch Berries a day! It's those damned blue crunch berries! With that in mind I can finally relax and enjoy my poos without fear. Thanks Dave J!

    christine's picture

    i was on the internet and i had 2 go 2 the bathroom really bad. it hurt when i was going and then i got up and noticed that it was green!!!!i started freaking out b/c i didnt know what to do. i suddenly realized that it was the blue slushes i had had at our town fair the night before. i was so relieved and now i can poop with out fear! thanx a bunch poop report!!

    We have something in common's picture

    Thanks for the info. I was a little concerned. At first I could not remember what I had eaten or dranked, but now I know it was the kool-aid.

    Wendy's picture

    Thanks.....I just thumbed through my botanical book and found nothing...almost fell asleep looking..went on and typed in "green poop" and to my wonderful surprise there was your article.
    My 10 year old daughter has had it once before, so getting it again made me concerned....of course the first time it just went away, yet being a mom I was a little worried at its' return.
    She had been to Friendlys at a birthday party, and drank a blue fizzy drink on Saturday and now 6 days later she is having brown stools with a darker green around it, like the green algae you find in ponds with frog sporn surrounded by the green stuff.
    I might still give her echinacea and garlic just

    looney's picture

    thank the lord for this web site.
    i was freaked out by my glowing green toilet trout i couldnt remember eating anything green in months, but when i found out purple koolaid does it, i remember not having any mixers for my gallon of whiskey 2 days prior. i ended up going through 2.5 gallons of grape flavor aid that night to finish the bottle.

    glad to know i aint dying

    Karli's picture

    Oh yeah, as a P.S. This is one of the most hillarious sites I have ever seen! Keep up the great work, and good luck on the PhD...I will be rooting for you!

    Karli's picture

    Thanks a pun intended. I had a greenie yesterday, and again today. Since I am 11 weeks pregnant, stuff like that worries me. Turns out it was the grape kool aid I drank yesterday - about 1 litre. Thanks again from Toronto Canada!

    jack's picture

    wow i went poop could not beleave mt eyes didnt say anything to my wife till the next day when i saw bright green ,went on the net,(google) typed in green poop to my supprise the first thing i see is why i poop green, wow thank god for people like you expermenting feel much better (lemon water ice ) did it thanks jack

    Vanessa's picture

    Little scared...poop was BRIGHT GREEN. Had 2 (big) bowls of Lucky Charms this morning. Now, thankfully, I dont think I am dying.

    Gretchen's picture

    You know the world is a great place when you can type in "green poop" on a google search and instantly get the answer!! I thought my 4 year olds organs were shutting down or something (paranoid Mom!), then I realized was that colored cone from her ice cream cone. Sshhhwww...

    Mike's picture
    m 1+ points - Newb

    Over the last couple of days mine's gone a dark-grey/green, but is giving off a red once it hits the water. Is this because I consummed 2 litres of pepsi the night before last and another litre last night?

    Treehugger's picture

    I drank some fruit punch at Panda Express and my poo was as green as a crayon. I am sure the dye was the culprit now- thanx poopreport for sparing me an anal probe!

    Steve's picture
    m 1+ points - Newb

    Black Licorice here. Chowed about 10 sticks and talk about flourescent green. Thanks Dave.

    Jenn's picture

    I too have been suffering from the leprechaun poo effect of the Lucky Charms with new green clover marshmellows (haven't they always had green clovers???). That is what I get for trying to eat a kids cereal. No more junk food food coloring cereals for me. Thank you for your site. It was quite a relief!

    Scott's picture
    m 1+ points - Newb

    The new mountain dew pitch black will do it to you also... it has blue 5 in it.

    Pitch Black's picture

    Pitch Black will give you well um Pitch Black pooo....or a very very dark green :).....happy loads

    person's picture

    well today i pooped green..but it was also kind of it scared me to death but then i saw this and i was wondering...yesterday all i ate was a little mcdonalds and then at about 11 PM i had a large blue hawaii icey from ralphs italian you think that caused it??

    Hunter's picture
    m 1+ points - Newb

    Well today I felt the turtle head pokin fun at my back door. I went to drop him in the tank and it was like he was trying to jump out. I think he was a kernel in the green peace. With a nauseous look on his face, he stuck his head up to the rim of the porcelain. He had to have been at least 14+ inches. And that's not by my normal calculations.

    hydrallus's picture

    I was f'ing around and being a smartmouth.. but I swear to christ my sh1t was green after I dare make fun of this sight. It was pizza luce in minnesota that turn my poop hippy green.

    Timothy's picture
    m 1+ points - Newb

    A mainstay of the Evergreen (ironically) State Fair is the "Purple Cow," a float with blackberry icecream, blackberry syrup and lemon-lime soda. My wife and I had it yesterday, and today--wow. I've never seen anything so green in my life. The Purple Cow has been around for a while, and I don't know if anyone has made the correlation before or not. But it's pretty popular, so there are going to be a lot of Washingtonians pooping green today!

    Marc's picture

    Today my poop was green and i wondered why so I looked it up on google and found this web site. It turns out its because I drank berry blue gatorade

    Doo the Dew's picture

    A couple cans of Black Grape Dew has turned my Doo Doo to Dew green... thank gosh I had this to tell me I thought I was dumping bile!

    Do the Dew's picture

    Black Grape = Pitch Black "with a blast of Black Grape" whatever flavor that is... I'm glad I'm not gonna die.

    Damn the Dew's picture

    Damn that limited edition Mountain Dew Pitch Black grape soda! All 6 of them today.... I too found myself wondering what the hell was wrong with me when i saw the BRIGHT green toilet paper swipe, did an internet search, and found my answer! Thanks! :)

    Rich's picture

    I'm at Airborne school at Fort Benning and have been drinking lots of Grape Gatorade on my off time to beat the heat of Georgia in August. Same results. The only other thing I've eaten is Ramen noodle/Korean noodle type soups/foods which have no coloring really.

    Monica's picture

    Thank you for the info!! I was in shock to see my 2yr old son poop bright green. I have been hitting the search ingine with anything that came to my mind, green poop, green feces, colored bowel movements etc. Then I come across this site... and what do you know? We just bout Grape Gatorade and he's been drinking lots of it! Anyway thanks, I'm off to rest now.

    Gizzle's picture

    Good to hear others are getting hit with the Mountain Dew Pitch Black Green Poop. I was talking with my friend about how recently my poop has been green. I put two and two together when it started happening after drinking large quantities of Pitch Black. My friend then told me my brother told him the same thing (who has been hooked on the Black Dew as well) yes, Mountain Dew Pitch Black, when taken in large amounts, will turn your poop green....

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