Dr.KarenChen said:

It helps to ask what evidence would change your mind before you look at any.

Adding the part of the answer the thread has not reached. The honest answer is that the effect is real, the magnitude is contested, and the individual variation is larger than either. Those three things can all be true at once, and most arguments here are two people holding different parts of that.

One concrete data point for the thread. If you are going to change something, change one thing and give it long enough to express itself. Four weeks is the usual minimum for anything pharmacological on this board, and two weeks of data has told you almost nothing.

Moderator note: the sourcing question belongs in the vendor section and has been split out. Tagging this one for the weekly digest.

PeptideChemSF said:

If you are going to change something, change one thing and give it long enough to express itself.

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.

PeptideChemSF said:

If you are going to change something, change one thing and give it long enough to express itself.

Agreed, and the size of the effect matters as much as its existence. Something real and small gets treated here as though it were real and decisive.