Dr.GutHealth said:

There is a difference between no evidence and evidence of no effect, and this subject is one where the two get swapped freely in both directions.

Coming at Dr.GutHealth’s question from a different direction. It is worth asking what the claim would look like if it were false. If nothing would look different, it is not a claim about the world and no amount of discussion will settle it.

The figures, for anyone assembling their own picture. 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.

If somebody has the primary source to hand I would rather cite it than paraphrase it.

A narrower follow-up, since the general answer is now clear:

How long did you give it before you decided it was working?

BiostatsBrad said:

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

I read this differently. The confidence in this thread is running ahead of the evidence, and I would rather the uncertainty were stated than smoothed over because it is unsatisfying.

OP back with an update, since a thread like this is useless without one.

Closing this out. What actually changed my mind was the point about waiting for a trend instead of reading a single measurement, which is embarrassing in hindsight and worth saying anyway.