HbA1c ticked up mid-cycle on BPC-157?? (probably nothing, still)

What lab and draw time? a1c is pretty stable across time-of-day but hemolysis in the tube can confound readings and some labs are worse than others.

Quest both times, AM fasted. So that should be controlled for.

a1c assay CV is ~3%, so the SE on a 5.1 reading is ~0.15. A shift to 5.4 is within 2 SD. You've got nothing here, statistically speaking. Combined with a 5-point fasting glucose move (CV ~4-6%) — also within noise.

I'd retest at week 12 before reading anything into it.

Summer/winter effect on a1c is a thing too (people tend to run a touch higher in winter). What months did you draw?

Baseline late August, retest mid October. So some seasonal drift possible.

Diet journal 100% honest? Holiday-season-adjacent snacking creep is the #1 cause of 'mystery a1c drift' in self-trackers and it's really easy to miss 100-200 kcal/day of carbs sneaking in.

...fair. I wasn't tracking strictly in September. You might have me there.

Also worth noting: BPC is studied for GI stuff and there's some evidence it shifts the microbiome. Microbiome changes -> SCFA changes -> subtle glucose effects. None of this is big enough to move a1c 0.3 points but it's not literally zero mechanism either.

Short answer: noise + probably the snack thing. Keep watching, report back at 12 weeks.

tbh the microbiome angle makes sense. I've noticed my digestion got kinda weird on BPC, nothing crazy but definitely different. And yeah the snacking creep is probably the biggest culprit here, that stuff adds up fast without you noticing. I'd just keep running labs every 4-6 weeks and see if it stabilizes or keeps climbing. If it keeps going up then maybe there's something worth digging into but honestly 0.3 on the a1c is pretty much noise especially if your fasting glucose is still under 90.

Yeah I ran BPC for like 10 weeks and my fasting glucose went from 86 to 91, a1c stayed basically flat though. Honestly wouldn't worry about it unless it keeps climbing at the next recheck. The snacking thing is real, I didn't realize how much shit I was eating until I actually tracked a full week. I'd just tighten up the diet for the next 4 weeks and retest, if it comes back down you know it was that.