BariatricNurseD said:

Vitamin D levels and micronutrients: an often-overlooked connection.

Iron studies on micronutrients — important especially for women:

My ferritin cratered at month 6 from reduced dietary intake. Iron bisglycinate 36mg with vitamin C brought it back up. Don't wait for anemia symptoms — test proactively.

The figures, for anyone assembling their own picture. If you are comparing against somebody else’s result, check that you are comparing the same measurement taken the same way. Most of the apparent contradictions in these threads dissolve at that step.

Dr.GutHealth said:

Iron studies on micronutrients — important especially for women: Marker Baseline Month 6 After Supplementation Ferritin 66 24 56 Iron 96 61 94 TIBC…

Coming at Dr.GutHealth’s question from a different direction. 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.

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

Was that from a primary source or from a summary of one?

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

Following up because I said I would. I changed one thing, left everything else alone, and waited the full interval before looking. It resolved, and I cannot prove which half of that did it.