[davepoiuy]

I was wondering why the volume of BM's can change so dramatically – does this have to do with how the material is being broken down (i.e. if it has passed through the digestive tract slowly are more nutrients absorbed, the bacteria breaks down the matter more thoroughly, more water is absorbed etc)? I am wondering because some days I pass not much at all and others I pass large volumes – was just wondering whether whatever is passed indicates that the bowel is empty or on the days where there is less it means there is just more matter being retained in the tract (i.e. whether the volume passed is a function of what is in the tract vs how much is being retained).

 

[Kathleen M.]

I think it just depends mostly on how much water is in the stool.Some of it is how much fiber remains as well. Some compounds will make the stools retain more water than others, and how hydrated/dehydrated you are on any given day may play a role.There usually is from 2-8 meals worth of residue in the colon so you usually aren't ever completely empty.I do think when stool move faster you don't get the chance to pull as much water out of it, so that can play a roll as well.There isn't much that you can say about what treatment or what diseases you have based only on stool volume, so it isn't a very useful measure.Some of the volume is bacteria cells, too, but I don't think it is enough in population changes day to day to make much difference.IBSers tend to notice all the day to day variation that is normal that they never noticed before. We seem to want to remember every single day was exactly the same, but they weren't and even with the same meals volume can vary between people.The nutrients are all pulled out in the first few hours, and that is before it gets to the colon, so amount of time in the colon doesn't change your nutritional status.