Could be your hypothalamus? I does help regulate things like that, and it is prone to radiation damage. Do you have thyroid problems? Are you taking medicine for it? That is the most likely culprit. Although getting a doctor to admit might be difficult, but if there are no other reasons for it, it must be from radiation. No different than any bodily function. The brainstem controls it all.
I’ve had stomach problems ever since my radiation treatment, decades ago. No doctor will say that my problems are related to the 6 weeks of radiation treatment I received. I think they’re clueless. Do any of you have digestion problems post radiation? Thanks.