Do sewage system designers have to consider the intestinal health of the users?

I ask because I was a little constipated today, and when things finally got straightened out the toilet was plugged - that little hole at the bottom was just a little too small for the dense slug that tried to squeeze through (talk about pinching a loaf!). Anyway, it occurred to me that in western countries, where inadequate roughage is consumed, toilets may need "looser" design criteria than in places where Big Mac is unheard of.