Answering the narrow version, because the broad one does not have a single answer. A defensible baseline is short: HbA1c and fasting glucose, a lipid panel with ApoB if you can get it, ALT and AST, creatinine with eGFR, TSH, ferritin and B12, and a full blood count. That set catches the things that change, the things that explain symptoms, and the things that alter the prescribing decision. Almost everything else on the long circulating lists is either invariant, uninterpretable without a specific question, or an incidental finding waiting to cause an unnecessary workup.

HPLC_Greg said:

A defensible baseline is short: HbA1c and fasting glucose, a lipid panel with ApoB if you can get it, ALT and AST, creatinine with eGFR, TSH, ferritin…

Agreeing with HPLC_Greg, and the qualification matters more than the agreement. One addition: if the lab changes analytical platform between your draws, the comparison breaks and nobody tells you. It is worth asking when a value moves inexplicably.

Ask again with the specifics and you will get a better answer than this one.

Dr.KarenChen said:

I got a full panel before starting and a repeat at three months, and the second one is more useful than the first purely because I now have something…

Same position here, arrived at the long way round. The single most useful discipline is bringing the whole panel to a clinician rather than one flagged value. One out-of-range result in isolation generates anxiety and unnecessary tests; the same result next to the trend and the rest of the panel usually generates a shrug.

From the other side of the consultation, briefly.

PSA: get baseline labs BEFORE starting baseline bloodwork therapy. You need a "before" picture to measure progress. My recommended pre-treatment panel:

1. CMP + A1C + fasting insulin
2. Complete lipid panel with particle count if possible
3. hsCRP, ferritin, B12, vitamin D
4. Thyroid panel (TSH + free T4)
5. CBC with differential
6. Liver panel (ALT, AST, GGT)
7. DEXA scan or body composition

Total cost at Quest without insurance: ~$200. Worth every penny for the data.