NurseLeah_Nash said:

Weight is a noisy signal — daily variation of one to two kilograms from glycogen, sodium and gut contents — so a fortnight of flat readings is well…

Saving this. It is the first explanation that did not require me to already understand it. Taking it to my next appointment.

Clinical perspective, offered as context rather than as advice. Worth answering the question that was asked rather than the one behind it. The narrow version usually has an answer; the broad version usually does not, and answering the broad one is how a thread stops being useful.

VanRx_Mike said:

Almost every unanswerable question in these threads is unanswerable because three things changed in the same fortnight, and no amount of subsequent…

I am going to disagree with the direction of travel here. The thread has converged on the tidiest answer rather than the best-supported one, and those are not the same thing.

One concrete data point for the thread. The boring version of this is the one that works, and the boring version is: measure a baseline, change one variable, wait, measure again under the same conditions. Nobody wants that answer and it is still the answer.

Moderator note: good thread. Keeping it here rather than moving it, because the question is general enough to be useful.