RoddyM

Hi. I'm not an endocrinologist but here's a few ideas.

I've had my BG's tested by a lab a few times, and twice I've used my meter at the same time that blood was drawn for the lab. I'm satisfied that my meter is accurate to within ~ 0.2 mmol/l (~ 4 mg/dl). I've also used my meter on clean hands to obtain 5 readings within the space of a few minutes on different fingers, and all readings were within 0.2 mmol/l.

Of course it is probably the case that the lab results are not always accurate. This means that no lab result is entirely reliable but multiple lab results along with comparing results to those of my meter decrease uncertainty. Or else I can say that although I may not be certain that my meter displays true measurements I can be pretty sure that serial readings over hours indicate true rises and falls. And that if my meter displays say 10 (180 mg/dl) that my BG might be 9.5 or 10.5 but it's still high, I should work to get it lower.

OK. You can probably see what I'm getting to. There are a lot of variables. For example my BG might be 120 mg/dl 5 minutes after getting out of bed at 8 am. I might be having blood drawn for fasting BG at 9.30 am. I've been told I can drink water or black coffee/tea. I might ride my bike to the nurse's office or I might drive. I might have gotten up earlier and done some housework or I might have gotten up just in time to drive to the office to have blood drawn. I might have spent six hours pulling out a tree stump by hand the day before.

Borderline fasting BG's tell us very little on their own. Even figures of 113 or 125. The surest way, in my opinion, to diagnose glucose intolerance (a tendency to hyperglycaemia) is simply a high carb challenge or glucose tolerance test. If you eat 4 thick slices of wholemeal bread your blood sugar might rise to say 140 mg/dl after an hour. You may then want to submit to further testing by a specialist to decide whether you warrant a diagnosis and treatment for diabetes.

Fasting BG, IMO, is of more use once you have established that you are in fact diabetic. Let's say you are "type 2" and on no meds the aim would be to get it as low as is practical. To see a meaningful trend towards lowering of fasting BG you would experiment by regulating timing of meals, sleep, execise etc. It seems my that fasting BG is an indicator of my compliance over the previous day few days. Also a low fasting BG seems to "set me up" for more normal BG's later that day i.e. that I can more "normally" and maintain near normal BG's.

In my case there was no doubt of glucose intolerance whatsoever. Four thick slices of wholemeal bread will raise my BG to 240 mg/dl.

The tricky bit of course is that people who are sitting at home wondering whether or not they are diabetic don't have a meter.

I diagnosed myself before seeing a doctor. I tested my urine on a hunch and found it was +++ for glucose. I bought a meter and experimented with it, learnt quite a lot before I saw a doctor. So far I haven't learnt anything from my doctor apart from the fact that he isn't particularly useful, :-).

Regards, RoddyM