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"

    cookie's picture

    Eating 3 bowls of Magic Stars (knock off Lucky Charms) (Dyes: Yellow 5 & 6, Red 40, Blue 1, Blue 2) and 3 bowls of Crunch Berries (Strawberry juice concentrate, Red 40, Yellow 5 and 6, Blue 1) for dinner will result in spinach colored poo the next day.

    Thank God for this site. I just spent an hour searching for 'green bowel movements' (good jumping off place if your 8 month old is filling his diapers with green gunk) and got nowhere fast. Got desperate and typed it 'green poop' and found this site. Nice to know I'm not dying or have been experimented on by aliens during the night, lol.

    Jesi's picture

    My poop's been green too. After reading this, I think it's all the Crunch Berrie's I've been eating!!

    The Green Growler's picture

    Man is this shit crazy, after drinking 4 packs of p-sarus rex I grew a tail reminicent of the swamp thing. Now I can't get enough of it. Green poo for ever. Ya-hoooooooo.

    The Green Growler's picture

    Don't even ask about the stench.

    Drinkin heavily's picture

    I had a week of heavy boosing in New orleans and was drinking copius amounts of blue gatorade for the hangovers. I started pooping green and almost had a panic attack because I thought I broke something! After about three days it went away and everything's ok...thanks dr. poo

    Mako's picture

    Wow, I'm glad I found this. I was freaked out, but I realized that yesterday I consumed a large amount of Blastin Berry Hawaiin Punch, which happens to be bright blue. Never knew that could happen!

    me's picture

    This is friggin hilarious!!! I looked online, because my poop has been green and getting greener until today, 3/14, when it looked as though someone had actually dumped bright green food coloring in the toilet. Then I read a few lines and noticed that I had eaten about a full giant box of crunchberries over the past 2 days. At first I thought that this was just my body preparing for St. Patty's day, but now I am edumacated!

    Minute Maid Grape Medley's picture

    You are really a genius. Thanks to you i'll be able to sleep peacefully tonight knowing that my colin does not have "gain green". I'd been drinking this delicious Minute Maid Grape Medley Fruit Soda. My poop was green and I was really starting to worry. I went on line thinking that I would learn that something really awful was wrong. I was getting sick just thinking about my obvious serious illness. Was I ever relieved to read your website. It did cross my mind that it could be the grape sode but I wasn't convinced until I read your website. Thanks for the very helpful information.

    Chad's picture

    After consuming roughly 500mL of Wild Watermelon Kiwi "Mad Scientwists" Kool-Aid, I had defecated a substantial amount of green poo... another test perhaps?

    chris in germany's picture

    i have been pooping , get this. AQUA green/blue poops. like lava lamp blue. and duh, it is the new fantastic FANTA berry blue soda, which i have been drinking like a crack addicts been smoking.

    thanks dr. poo from germany!


    djgidget's picture

    Blueberries can also have the same wonderful, Kelly Green. It doesn't matter if the berries are fresh or frozen, the same results will happen, and it doesn't take very many of them to have the smallest effect.

    poopstain's picture

    Grape Koolaid strikes again...making yet another hit for this site...glad I found it anyways, lots of interesting facts on here...hehe

    Krystle's picture

    WOW what a relief it is to have found this site! I am another one of the college kids who eats nothing good but crap snacks. To my surprise i went to "drop a spirit stick" as my roomate calls and saw bright green poop! The last thing i wanted to do was call my mother and say i needed to see my doctor because i have green poop! Thankfully i typed in green poop on google and found this site! I didn't realize that i had been eating alot of fruit gushers. So there's another one to add to the list of green poopoo! Thanks alot for saving me an embarrassing call home to mom!

    Sandi's picture

    Ya know, it is so funny, how this study of yours, which is really funny in reality, has actually helped many concerned moms. Moms get freaky at the site of a strange colored poop coming from their children. My 2 year old daughter had the brightest green poop I have ever seen. I was only mildly concerned since I have had this situation with my other daughters. But it seemed so bright I got on the net and sure enough found your site. What has my daughter been drinking this week you ask? Well sippy cup after sippy cup of purple kool-aid. LOL. Thanks so much for this interesting and yet strangley helpful study. :-)

    Jon's picture
    m 1+ points - Newb

    i had neon green poop 2 days ago and i only drink water because i am dieting and all i had to eat eas velvetta light shells and cheese!! so whats up with that?!?!

    Melissa's picture
    m 1+ points - Newb

    Grape Gatorade is yet another culprit for the bright green poop! Bottoms Up!

    Cody's picture

    I just had a nice green crap, and I told my friend about it... She thought I was a whack job. I always thought it was green when you are sick, but it might just be coincidencial that it's green usually when I'm sick... I told her about it, and I came on the interweb to get proof, and found this site... Awesome tests by the way.

    magiklogs's picture

    After eating some really cheap generic brand of froot loops, I noticed that if I had a big enough bowl of the stuff I shit purple-blue. The cereal had a lot of blue and purple rings which was the culprete of my ghastly almost black poo. Also some medecine capsules are made with a certain dye that turns poo green. Antibiotics (some not all) also make poo green. I hope all this info helps someone reading these messages. I know I was Pretty scared when I first started taking anti-depressants and I shit green, but I soon realized that it was the blue/red capsules that were doing it.

    Dumbass's picture

    Maybe this "concerned mother" should stop feeding her kids tripe like kool-aid. Ingesting all that food colouring is gonna give them cancer.

    Sara McHanson's picture

    Dear Poopreport,

    I love you. YAYEYAYE

    crank's picture

    ive had green poop for like 2 months straight, and it must be the fierce grape gatorade. i go through about 3 bottles a day!

    Snackycakes's picture

    I really enjoyed your sight, especially being a nurse and knowing how frightened we all get when something abnormal comes out of orafices. I for the first time drank alcohol in,well, a long time! I bought thed Fierce grape Gatorade and it led to some fiercer green diarrhea. On top of it I have to take laxatives due to IBS (irratable Bowel Syndrome) Makes for a nice trip to the ladies room. Anyway another thing that changes our poo green is licorice. Check it out next time you go to the movies, you will have a show of your own. LOL! Tata for now all!

    wade's picture

    i had a large blue slurpee and the next day i enjoyed observing green feces in the crapper !
    pretty cool stuff

    Colon Pal's picture

    As a man in my 40

    Glad to know's picture

    My son who is special needs is tube fed....Last night and today the poo was quite green...After reading many posts I have now come to the conclusion its the purple pedialyte he is on...This has recently been added to his diet due to dehydration so I'm guessing this is the culprit!..Thanks!

    Relieved's picture

    Thank you so much! For a couple of days my poop has been green and I started to get worried. I recently went to the movies and I had a blue slushie and realized that the blue dye must have been turning my poop green.
    Thanks again!


    The Shit Volcano's picture
    Comment Quality Moderatorh 3000+ points

    I've been eating a lot of strawberries and raisins in the last week. My poo has been pink! That's one to add to the list of colors and it's all natural, too! Organic pink poop.

    I found Jesus! He was behind the sofa the whole time!

    POOP FICTION's picture

    I just took a monster dump and peeked into the bowl ... omg I saw something round, tough and GREEN, it's the TEENAGE MUTANT NINJA TURDS!!!

    PoopGoesTheWeasel's picture

    I looked in the toilet and what did I see? A plump green doodie was a lookin' at me. I tried to flush it, it kept swirlin' around, this turd was too fat, there's no way it was going down. It said "Why do you drink Berry Blue Typhoon, and poop me out green like mold?" I said "I got the plunger, so do what you're told!"

    the green lantern's picture

    I went online for the same problem as most of you guys. The green stool has been driving me nuts! I now realize that eating a blueberry snowball from ice planet is the reason why its this way. GREAT site!!!!

    Lorrrin's picture

    Wow that a load off my mind, I've been drinking blue shasta not even alot of it and my poop was green to. It must have alot of that dye in it.

    Annonoymos's picture

    I just recently had the same problem of green poop and because of this site realize there is nothin wrong. Another product besides kool aid to use would be SPARKZ
    Vodka Blueberry. man did it ever go green.

    Oh ya you must be 18 to drink it

    me's picture

    i was making chocolate candy yesterday trying to get a dark blue color. i eventually was happy with it (after lots of food coloring) and tried some before i give them away as gifts. poo...after only 2 pieces of candy!! i think i might give my friends some sort of disclaimer when i give them the candy was blue Wilton candy colors(oil-based)

    Grrrrrrreeen poop's picture

    This was definitely a helpful site, MY GREEN SHIZIT WAS DUE TO JUICE BOXES. It was a new kind, some "Berry Berry" shit. I thought I was dying , but no more.

    Kim's picture
    m 1+ points - Newb

    I am so relieved to find this website. I went to
    Disney's Animal Kingdom last Friday and tried to
    be a fun mom by getting a tube of the blue powdered sugar that is being sold in many candy shops. Lots of blue dye as my daughter and I can
    attest too as we laughed at each other's blue lips, tongue and teeth. It was no laughing mattter though when my feces began turning the most brilliant shade of green I've ever seen the next day and several days after. I thought I was
    dying of some horrible intestinal cancer. Thanks for all your hilarious stories of green poop!!!

    poopmeister's picture

    captain crunch crunch berries w/ rugrats movie shapes have lots of blue, purple and green dye. i ate several large bowls of cereal combined with several micro-beers that evening, and voila, eureka, i crapped green as springtime. i'm attemping a repeat as i write.

    Minute Maid Fruit Punch and Crunch Berries!!!'s picture

    well... after a night of drinking vodka and a TON of Minute Maid Fruit Punch.. plus eating 2 bowls of Crunch Berries... i crapped green! i freaked out but then found this site.. thanks for calming my fears lol

    green poopies's picture

    chinese food give me green poopies!!! i tell man, you food give me green poopies, he say NO, NO GREEN POOPIES. I get green poopies from chou-main noodles!!!!! he say NO YOU NOT!!! GET OUT!!! i still have green poopies :(

    spoof's picture

    green poo for the first time today. Thought i had some strange disease or something. after reading this realised it must have been the bright blue slush puppie i drank yesterday, thankyou for puuting my mind at rest and saving me from an embarassing trip to the doctors!!

    Green poo's picture

    I was freaking out over green poo until I found this website. I figured out that the culprit for me was blue rasperry licorice. Thanks for the help!!

    Angel Heart's picture

    I ate some sugar cookies that had blue icing. Could it be the reason for my green poop?

    J Hall's picture

    Black licorice definately causes this to the max. Thank goodness I found this site, I was beginning to freak out. :)

    Pooper Man's picture

    Wow, It seems that Mountain Dew when consumed in VERY large amounts can have the same affect. I am suprised that no one has said anything about it yet.

    Bodacious Berry's picture

    I've been shitting green for about a week and was getting concerned. I had an ulcer problem a month ago. I realized i started drinking bodacious berry hawaiian punch recently in large quantities. That is probably it.

    Gary's picture

    I ate a blue snowball and when i looked in the toilet i thought there was a plant growing in the anyway after reading this post i now understand why..and my only question is how can i make my poo blue!! that would be awesome... lol. emali me please if you know.

    cassie's picture

    since i was 2 ive been shiting brown whats wrong with me

    burnadette's picture

    I couldn't figure out why my poop was bright green for several days and after reading some of this I realised that it has been caused by my eating a bag of black jelly beans over the past few days - I thought I had some weird medical condition and was starting to worry...

    Niece's picture

    Definately Captain Crunch Cereal with Crunch Berries. It does make some lovely grass green berries!

    Hybrid's picture

    Drinking copious amounts of Pepsi Blue has the same effect, thats why I'm here looking to see why my poop is luminecent green, cheers... You would have thought after years of testing different PEPSI products they would have noticed this rather disturbing side effect...

    Concerned Wife's picture

    Thank you for the relief your site administered! My husband had the "green poopie" blues also and was getting kind-of worried about it. I decided to get on the net and see what I could turn up, and here it was. I found my ansewr with the first search of "green feces" and my husband is forever greatful to you all for being strange enough to share your deficating stories with the world! By the way, his culprit was a bag of Gummy Bears! Funny!!!

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