Raisinoak, it's good that you have been able to pinpoint a pattern to your odor. I guess whatever is responsible for your odor can't be all that smart after all since it has clearly left a pattern here. Now our job is to associate this pattern with a culprit (the right suspect).
i also notice that i smell strongly of anything in my rectum/anus. most people have a smelly rectum/anus as well - at least i know this when im giving guys oral/blow jobs (LOL). But why is our own anal/rectal odor so amplified such that outsiders can smell it from miles away?
Could it be that we have more gut bacteria than the general populace (and not necessarily just more bad bacteria but more bacteria in general)?
Is there a test for the total amount of bacteria in one's gut?
Like you pointed out as well, it is possible that we have a localized infection in the anal/rectal region as the reason for the smell.
Well yeast/candida is also something very real!!! I was drinking juice directly from a bottle while eating. I didn't finish that bottle of juice, and I left the bottle covered and laying around somewhere. Many months later I discovered that same bottle of juice and (guess what y'all) it already has a whitish stuff growing in it. Yeast is real y'all!!! Now I wonder why wouldn't that whitish stuff that is growing in the bottle of juice also be growing in me. I'mma open that bottle of juice and report back what it smells like in my next message. I'mma save that bottle of juice as well. And I suggest that y'all try the same experiment so y'all can show it to your doctors how easy it is for the whitish (candida) stuff to grow when your saliva touches anything (like in my case with the juice bottle)!!!