Clinical perspective, offered as context rather than as advice. Most of what circulates confidently in this community traces back to one summary of one study, and the qualifier was dropped somewhere in the third retelling.

anders_CPH said:

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

Coming at anders_CPH’s question from a different direction. Take it one variable at a time. Almost every unanswerable question in these threads is unanswerable because three things changed in the same fortnight, and no amount of subsequent argument can untangle them after the fact.

Happy to go further on any of that.

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.

Following on from anders_CPH — and this may be the naive question:

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

Moderator note: two posts asking for a source have been merged into one. Please search the thread before asking again. Report rather than reply if it drifts again.