In my case, I experience a wooziness and general malaise for an hour or two after each BM. Sometimes my gut actually feels as if it has gotten warmer. Been like this for decades, to varying extents. No one has been able to explain it, but my theories are as follows: Everyone knows that the colon is where moisture is normally drawn back out of what remains after the rest of the guts have done their work. After a BM, a new batch of material moves into the colon from the small intestine. This bolus of material may contain a bunch of stuff that did not get absorbed yet, to which one may be sensitive. If there are water-soluble toxins in the food or as byproducts of earlier stages of digestion, some portion of it will be absorbed there. The problem might be as simple as too much moisture being absorbed all at once and causing a mild electrolyte imbalance, or excessive salt in the diet reaching the bloodstream at this time to similar effect. I have heard that there is a condition called "leaky bowel syndrome", where it may even be possible for all kinds of insoluble stuff to leak into the bloodstream during this process, i.e., lipids, lipid-borne compounds, oligormerized proteins, extremely fine carbonaceous or inorganic particles, etc.. If one's food contains something that should not get into the bloodstream, whether due to allergy or generally speaking, this may be when it actually finds its way there. Also, there may be less than friendly bacteria cohabiting with all the friendly ones, and this may be when their toxins are absorbed. How to prove any of this or determine what might work as a treatment is beyond me. Checking lipid levels before and after a BM might be interesting. Running a GC on the blood plasma before and after might be interesting. Relatively methodical dietary alterations to isolate what I am allergic to have not really produced any useful data in my case. BTW, don't lend any credence to people who claim to have training but still suggest that this may be psychosomatic. Some people will say or write absolutely anything just for the sound it makes or to avoid admitting to not knowing an answer.