It can be caused by a lot of green vegetables like spinach but it does not sound like you have eaten enough for that to be the cause.

More likely is that the green colour is caused by bile. Bile starts as a yellow/green colour and becomes brown in the colon as the bacteria there help to break it down. If the contents of the gut move too fast or the bacteria as disrupted the green or yellow bile ends up in the stool unchanged. Green stool and diarrhea can be a symptom of salmonella infection for this reason. Also babies commonly have green stools as they lack gut bacteria to digest the bile.

Interestingly a average adult releases about 1 litre of bile every day for digestion. Most of this is normally reabsorbed by the body.

I would speculate that if you suddenly start eating lots of fat and little fibre you produce more bile and the bacteria in your colon will be disrupted for a while. A dose of bile may have just gone straight through you.

It will have nothing to do with remnants of your prior diet.

If you are worried about it, symptoms continue or you get any other symptoms go and see a doctor. As well as asking random people on the internet.

As for timing, four days is awhile but you've made a radical change to your food intake. Your body is trying to figure out what to do with all this new, nutritious food. I often go 2-3 days between dumps. Don't worry about it. The fiber fanatics would have you think you MUST crap daily, preferably several times a day. Nonsense. Yeah, if you fill your gut with "heart-healthy" fiber and grains you'll be crapping a lot, but it doesn't mean it's good for you. There's a sign in our work cafeteria that scolds us to "fill up on fiber", which has zero nutritional value. Whee. Real food leaves little waste. Oh and I never eat from the cafeteria.

Green poop, well, maybe that spinach was enough. If it's constantly green, get it checked out.

I personally like to go on at least a daily basis. Less and I feel bloated and gassy. Increasing my fat intake ususally "cures" any backlog. As for the greenish color, I don't know anything about bile but I have been iron deficient at times (pre-Paleo diet condition that continues to go undiagnosed, but I digress...). When I would try an iron supplement, I would poop dark green (think the really mean looking, angry Hulk cartoon). I don't know if you are on a supplement but lots of undigested iron can cause green bowel movements.

I had this same problem, ranging from light clay yellow to green stools when I went strict paleo. I believe that it is a lack of bile. It is bile that turns your stools dark brown, before that point, the stool is greeny/yellow. I found that by taking one tablespoon of the purest olive oil I could find for three evenings, just before bed, resolved the problem.

I'd been eating paleo about 10 months when that happened - no change in diet that I could think of, but suddenly, for about 4 days, I had this deep green poo - almost moss coloured. Then back to normal. I actually wondered about posting but was too embarrassed! So thanks for bringing it up! And it hasn't happened since, if that is of any comfort.

What have you been eating?

The most common cause of dark green stool is the ingestion of a lot of greens. If that's the case, you have nothing to worry about. There is a possibility of having salmonella or food poisoning, but it doesn't sound like that's the case.

Dark green stool is rarely associated with a health issues. It sounds like your body has started to re-regulate itself, and the color is a result of ingesting a lot of veggies.

Raw green veggies? Particularly the tough ones like kale, collards, swiss chard. It's all the stuff thats in season right now anyway.

Not that I want to put myself up here as the expert on poo but my experience has been raw green vegetable have given me the green flush. Been eating a lot of raw kale lately? Indulging in Mark's Big Ass Salad?

Raw vegans will tell you your body is flushing out all the impurities of course. <-uncontrollable laughter->

I notice when I drink a lot of butter water my poop comes out in hard green balls like Type 1, I've always thought it might be unabsorbed bile, sometimes I see some yellow spots I swear look like undigested butter, but not sure, I eat about 250g butter a day.

I notice when I increase my protein above 0.8g/kg my poop starts coming out more normal like Type 2.

Green stools often indicates a lack of bile as many have suspected already, and usually means that you are not appropriately absorbing your protein, in particular. If you come from a SAD eating background, your TGI tract might be inflamed. I would recommend a good probiotic and something as simple as papaya enzymes until you get more balanced.

Hello! I am very new to Paleo and have also noticed the same dark green stool. I have been eating lots of spinach and romaine lettuce so I wasn't very concerned. Its been happening for about 3-4 days now. After reading about how bile/bacteria changes the color of stool as it passes through the GI system a light bulb went off! I am unfortunately taking a strong anti-biotic for a bad skin infection. I must have been cut and some bad bugs got in there. I had MRSA once in the past. The Doc wanted to make sure I wouldn't have to go through the same awful experience as last time. I have about 6 more days of Bactrim to finish. Once I am done I am going to load up on the papaya and get some pro-biotic yogurt to reset my system. To the OP, have you recently taken an anti-biotic due to some sort of infection? Hopefully this can help! I know the post is old but there has to be some other people out there with the same issue.

Cheers!

if i drank any grape coolaid my poop turns bright green. back in the old days it was funny, now i know those dyes cause cancer so its no loger funny.