LibrarianMeg said:

Order of operations matters more than any single choice here: establish a baseline, change one thing, wait long enough for it to express itself, then…

That is right for the common case. Whether it is right for the case being asked about depends on a detail that has not been given.

LeilaHI said:

True, and anyone with reduced kidney function needs that target set by a clinician rather than a forum.

This is exactly what I could not find anywhere else. Printing the relevant bit and taking it with me.

LibrarianMeg said:

Order of operations matters more than any single choice here: establish a baseline, change one thing, wait long enough for it to express itself, then…

Filing a mild objection. Mild because I might be wrong; an objection because nobody has addressed the case that does not fit. Pushing back on the anecdote-stacking. Twenty people reporting the same thing is twenty samples from the same self-selected pool, not twenty independent confirmations.

Adding the numbers, since they settle part of this. For anyone reading later: the numbers in this thread are worth checking against a primary source before you act on them, including mine. Half the figures circulating in this community trace back to a secondary summary that dropped a qualifier.

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