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16 Feb 2009

Green stools
The problem - the colour of my stools is GREEN i.e. after each marathon or longer. I swallow about 3 GELS during a marathon but the number can increase to 6-7 for Comrades BUT I’ m not certain if that is the reason for the colour. The question is –  should I be concern?

i do not swallow any gels during a 21km or shorter races and I do not have the problem
Answer 405 views

01 Jan 0001


I must confess I've never heard of green stools as a result of running. Red yes, that's fairly common, but I've not heard of green. I can't see how gels would cause that.

I am reliably informed by some research on the internet that green stools can result from the rapid movement of feces through the intestines. Bile is green, and so the rapid movement of stools through the intestine prevents bile from having its effect and green stools are the result. That seems the only explanation I can find for it, and no mention at all made of anything to be concerned about. Obviously, that's not a medical opinion and you might cnosider finding out, but I suspect it's nothing to be overly concerned about.

Good luck
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