Happy, but confused by most recent blood work

So, I just got my most recent set of blood work and the numbers are very good. That makes me happy. What makes me very confused is that these numbers are very close to my numbers from 6 months ago, but I have been not living the same lifestyle over the last month or so as I was in the 4 months prior to the last set of tests. The only difference that should help is that I am now on metformin. Is it really that powerful?

In April I have spent the previous 4 months following a very low carb diet and being very careful about following my numbers. I had been getting enough sleep and work was not especially stressful. My fasting glucose number was 87, my A1C was 5.8, and my c-peptide was 0.62 (scale of 0.8 - 3.10). Due to the low c-peptide and the fact that I was eating as good as I could and my A1C was still pre-diabetic (I was gestationally diabetic 3 times, but since then only diagnosed as pre-diabetic) the doctor prescribed metformin (500 twice a day).

Since the end of August work has been extremely stressful, I have been getting little sleep (due to all that work), I have had little time for exercise and I have been eating terribly (not paying attention to what I put in my mouth - just going for what is close by and will give me energy). All of those things that are supposed to worsen my numbers. I have been rarely checking my numbers since I didn't believe I was going to be able to do anything about them and I didn't want to know. So, my blood work came back today and my fasting glucose number was 85, my A1C was 5.8, and my c-peptide was 0.82 (at the low end of the normal scale). So, either my lifestyle makes no difference to my blood sugar numbers or metformin is making a HUGE difference.

Or perhaps, I just get strange lab results. Maybe I am super insulin-sensitive (despite history of hypoglycemia and three cases of early development of gestational diabetes) and a high glycator.

Again, I am very happy, but confused. (All my numbers were good - blood pressure 102/64, pulse 52, HDL 63, LDL 91, triglycerides 35, BMI 21.7. Apparently I should always be stressed out, getting little sleep, little exercise, and eating poorly!)

Metformin, for many people, is extremely effective. In my case (LADA w/ insulin resistance), I once had to stop taking it due to some other procedures while an inpatient. I did not take it for 6 days and in order to maintain reasonable BG level I had to increase my basal insulin by 125% - 200%, but had to increase bolus insulin by over 300% depending on if I as eating (and what I was eating) or not.

There were a few days while I was hospitalized, that I could not eat at all due to some tests and on those days I kept my basal at it's normal setting (no food, no bolus) and maintained 90-100 BG levels.

Plus stress does different things to different people. I generally go low when stressed to a certain level, and then go high when exceeding that level - all else being equal.

Plus I'm on a few other meds that each what to screw with my BG in their own unique way.

And of course this was all completely different when I was on MDI vs the pump. Back then my pancreas would randomly intervene and dump insulin and toss a monkey wrench into the whole process.

I know this might seem like an odd statement, but I'm sort of glad that my beta cells have finally given up completely (for the most part).

In patients that have an A1c of over 8% metformin was found to reduce their A1c by 1%. That is a pretty big drop and suggests that it is pretty effective. But those patients had high blood sugars. You have been having really good blood sugars. You already had a nearly perfect fasting number and you were eating low carb. You should not expect metformin to make much change and certainly not a drop of 1%.

And remember that even the absolute best labs that have been accredited by the NGSP still only have A1c results that are +/- 6%. Your A1c of 5.8 could actually be between 5.5% and 6.1% and still be considered perfectly accurate.

I understand! I am very happy my pancreas is doing as well as it is, but the inconsistency can drive me crazy. When I first started tracking my numbers I had this belief that I would just identify the conditions that I should avoid and then I could stop checking. There was no logic or sense behind any of it! One day I would eat a low-carb meal and my numbers would be good, the next day the same meal would no longer give me good numbers. Same for higher carb meals. It all depended on what my body decided to do with respect to the amount of insulin it produced and I had no control over that.

At this point I just plan to keep taking the metformin and hoping things stay good for as long as possible. My doctor said it would be great if I could delay getting diabetes until in my 60s (I'm 40 right now). I've tried actively doing what I can, now I just need to cross my fingers and hope things stay good!

Thanks! Yes, I am aware the A1C is not a precise test. However, my numbers for that test have always hovered right around 6.0, so I figure that is probably close. My main concern (and that of my doctor) is that given my lifestyle and family history I should not be anywhere close to diabetic. But I clearly have some kind of genetics working against me.

When I first started on the metformin I didn't really expect it to do much since I don't have any signs of insulin resistance (the opposite, actually, since my c-peptide is low). I don't understand how it works, but I have become a believer!

At this point I plan to keep doing what I am doing (or go back to what I was doing as soon as work allows) since it seems to be working for me. My A1C hasn't really budged with all the life changes, but my fasting numbers have dropped from around 100 to under 90.