Oh my God… and to think, I wasted my 1000th post on that!
E3.
While traveling with a youth performing group this summer (a drum and bugle corps), they decided to replace our orange drink with purple. (That’s just what they had leftover). A day or two later, we had one of our nightly reststops. Normally, most people would be nearly asleep, stumble off the bus, go to the bathroom, and get back on the bus. This night, however, a bunch of them came back wide awake and talking loudly. Apparently they’d all had neon green feces. Scary thing at 2 in the morning.
Dear Heaven Almighty! :eek:
I used to be able to outgross anybody in the room…but on the Internet, I’m not even in the running…
<minor hijack>
Blue dye is supposed to cause blue pee, but the blue dye on the Diurex (water pill for menstral bloating) makes your pee green. Doesn’t that sound more correct, anyway? Yellow and Blue do make Green after all 
It’s a bit…unexpected, though, since there aren’t any warnings like that on the box.
<minor hijack>
There must be something particular to grapes that cause green poop, besides the dyes in juice. Even white grape juice, which isn’t dyed purple(it’s yellowish), causes it if you happen to drink 2 quarts of the grape juice in a 24 hour time span.
THAT IS TOTALLY GROSS!!!
As I said before - GET A LIFE!!!
ZombiesAteMyBrain, this is General Questions. Opinions belong in IMHO or the Pit.
SO, if someone asks a question. I’m not allowed to express an opinion on whatever answers come up???
Who died and made YOU God???
Mince off!!!
Now, now, kids. Play nice.
ZAMB, Ed is God, at least on this message board, so I suggest you take his warning to heart and react in a less hostile maner the next time someone tries to help you out by nicely pointing out the differences between the foura.
Zombie, the occassional opinion in GQ is fine if it doesn’t come off as judgemental. Start up a Pit thread if you feel you must.
Telling off longtime respected Dopers, OTOH, will turn your feces green. 
IANAD, but greenish stools can also be an indicator of occult blood in the digestive tract. This can range from the totally begnine having ingested a large quantity of perhaps too rare red meat to the more serious bleeding ulcer or colonic cancer tumor. If this symptom is infrequent and transient, everything is PROBABLY OK, otherwise, hie thee to the gastrointerologist and get it checked out.
A few years ago in late October, I stopped at a bagel shop and bought a special “Halloween” bagel that was 1/2 orange and 1/2 black. For a week after eating it, my feces was green. I can only assume that the black food coloring was somehow coming out green, and that they used a ton of it, since it took several days to flush it out of my system.
I had an upper G.I. a while ago, the barrium was white and so was my…
Also, once in my youth i went on a seriuos carrot binge for almost a month, Practicly the only thing i ate was carrots, and my … was the assumed color of the carrots, It al depends on what kind of dye is going in. Also whenever i had the flu or was sick in general my… was green.