Some people report seeing 'white rice'in their stool, is that what you are seeing? If so, then it COULD be a sign of tape infections, take a look at these images:
Sorry if this causes concern - there can be a number of pathogens that can harborthe gut, so often times it is better to test with compentent labs. ParaWellness Labs is one of the better parasitic labs - last time I checked, the cost was around $300.