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Fasting question

WilliamEE

Well-Known Member
Messages
86
Type of diabetes
Prediabetes
Treatment type
I do not have diabetes
Hi,

I am new to the forum.

Two and a half years ago my a testing of my fasting blood sugars read 5.8.

My doctors then arranged a Glucose Tolerance Test which came out fine:

5.5 Fasting
5.5 2 Hours

I just had my cholesterol and blood glucose tested again and my blood glucose are now 5.

However, I didn't have the blood drawn until 16 hours after a meal.

I have checked with the lab, my doctor, a nurse and a Diabetes Hotline if the 16 hours would give me an incorrect result and they all said it shouldn't. I might be 5.2 or 5.3 but that's about it.

Also before the blood was drawn the doctor tested my levels on a metre and they were 6.2. Clearly the monitor was inaccurate. I also have a monitor at home and whenever I have tested myself have never been over 5.8.

I'm really worried that I fasted too long and this may have affected the result. Does anyone know if the amount of time fasting (i.e. 12 or 16) makes very much of a difference?

I really regret not taking up healthier eating habits back in January 2012 when I got the result of 5.8/5.5 but am now going to stop eating certain foods like biscuits, cakes, pasta, rice and bread (bad carbs basically).

My weight has been stable during this time and I work to work every day which takes 35-40 minutes. I also walk home but some days don't feel like it an catch the bus.

I don't want to become pre diabetic and more so diabetic. My father was diabetic and there is diabetes on my mothers side (she had blood work done the same day and was 5.1). I am nearly 52 and weight about 84kg, though I have lost a couple in the last two weeks. My aim is to get to 70kg.

Does anyone know how rapidly blood glucose drop when fasting?
 
WilliamEE

I think potentially everybody have different swings on different days and it can be affected by what you have eaten maybe up to 48 hours earlier.

I can go to bed at midnight with a reading of 5.5 and first thing in the morning it can be 7, I can also go to bed with a 7 and get up with a 5.5!

It doesn't answer your question but it isn't an exact science.

jim
 
Hi and welcome,
Ill try and give some answers.( Type 2)
Usually Diabetics test 2 hours after a meal, when the Blood Glucose level should be back to the level when you started eating. This however depends on what you eat.
High GI Carbohydrates increase blood Sugar.
Blood Glucose testing meters can be out by up to 20%, and are really used to see what food does to your blood sugar.
Usually people test before a meal and then after a 2 hour period,
The following is worth a read
http://www.diabetes.co.uk/diabetes_care/blood-sugar-level-ranges.html.
As will be seen your figures are excellent and do not indicate Diabetes
With regard to fasting, normally 8 hours would be fine prior to a test.
However your liver will dump glucose into your blood stream at some stage, as it thinks you are starving and this will raise your glucose level
So a Fasting blood test is really only an indication of your Blood Glucose when the test is taken.
If they do a HbA1c test, this gives a true reflection of your Glucose over the last 9-12 weeks. this is the most accurate check.
I think the fasting was more for the Cholesterol test, as anything you eat in about 8 hours will influence the test results
If there are any more questions, please ask, someone will answer
Go Well
 
Hi Jim,
I think in your case that is typical of a liver dump, happens normally before you waken in the morning.
In the case were it was low you possibly had something to eat, or went to sleep later
 
The earliest blood test appointment I can get is 9.30, as I eat my evening meal before 6.00 most days I normally go 15 - 16 hours fasting before a test.
 
Ruth B said:
The earliest blood test appointment I can get is 9.30, as I eat my evening meal before 6.00 most days I normally go 15 - 16 hours fasting before a test.
Click to expand...
What sort of test?
 
Hi William and welcome to the forum.

I have to say that I agree with Randburg, your figures do not indicate diabetes, in actual fact, your figures are very healthy.
 
Thanks everyone for your posts. I really appreciate them.
 
Hi
I am new to the forum. I have been diagnosed as a diabetic with the result of blood test results of 5.1 fasting and have been prescribed Metformin 500mg 3 times. I have not taken the tablets yet as I want to understand blood sugar levels etc. After reading your comments I am not convinced I fall under the diabetic category and cannot understand why my doctor prescribed the medicine in the first instance.
 
Hi @Kali

Maybe you could check that figure with the doc, and ask their reasoning?

I was given metformin years ago when I was prediabetic, for another health issue, so it does get prescribed for different conditions, and can (if I remember correctly) help weight loss.

If you do have normal blood glucose, and take largish doses of metformin it will lower your BG a little. There are a couple of people on the forum who have needed to lower their metformin dose as they have normalised their blood glucose (because it was taking their glucose levels too low).

Like you, I always want to understand the 'why' and 'how' of things. So keep asking the doc til it makes sense to you!
 
Hi Kali and welcome to the forum.

As Brunneria says, a fasting BG of 5.1 would be really good for a non diabetic, so I am also confused? Have you quoted the right figures? If you have you should go back to your GP and ask for an explanation.

jim
 
Hi Jim

I consider myself as a non diabetic after seeing the posts above, and because I went to get my blood resuts (fasting) for which i was called in to discuss on 3rd July and have not taken any tablets yet, My GP stated that it had risen to 5.1 from 4.8 that was last year in August 2013 and 5.1 is classed as diabetic and prescribed me metformin 500mg 3 times a day starting with 1 tablet a day for 1 week, 2 for the second week and 3 a day from then on and go and see him after a month when he would refer me to the diabetic clinic. I have no clue about these figures and thresholds etc. and am trying to educate myself now. My fasting time was a gap of 11 hours. I happened to have a late dinner around 21.30hrs and the fasting test was 08.30 hrs. I am 61 and vegetarian and fond of eating all the junk food sweets and savouries and lots of carbs. Have never counted calories and used to eat chips 3 times a week until 6 months ago. I have lost a stone since then and went to the doctor to request for a blood test because I was worried about the lost weight. I was 87kg now down to 80kg. I do not excercise. I know now that I need to eat and excercise / brisk walk etc sensibly. But i am now in a dilemma going back to the GP and get clarification again. I am positive he stated 5.1.
Kali
 
Hi Jim

I consider myself as a non-diabetic readind the above posts and because I have not taken the Metmorfinthe GP has prescribed to me when, I went to see him to discuss my results on 3rd July when he stated that my fasting result was 5.1 a rise from 4.8 last year in Aug-13.

I am 61 now weighing 80 kg down from 87kg six months ago after cutting down on chips consumed 3 times a week. Overall I am a junk food eater sweets and savouries and lots of carbs. I dont excercise. I am now confused and yes I have to get an explanation and educate myself on diabetes. I have no clue about all those figires.
 
I would ask for a print out of the results so that you can be sure you are getting the correct figures. Something is weird about this result.
 
Hi,
I agree the figures you are showing do not indicate Diabetes,
Blood Sugar 101 says this on what is normal
" Doctors consider any fasting blood sugar between 70 mg/dl (3.9 mg/dl) and 100 mg/dl (5.5 mmol/L) to be normal. But several studies suggest that people whose fasting blood sugar is over 92 mg/dl (5.1 mmol/L) are more likely to be diagnosed with diabetes over the next decade."
http://www.bloodsugar101.com/
I would ask your Doctor to advise why he put you on Medication, as you are within normal limits
Let us know

I think if you had a HbA1c blood test, that gives you an average Blood Glucose reading over the last 9-12 weeks may be the way to go to resolve your situation, maybe ask the Doc
 
Hi. Overall your levels look very good. A delay of 15/16 hours before fasting test is too long and could affect your results due to a liver dump pushing the blood sugar up not down. A phlebotomist once told me to try to stay near the 12 hour time limit. I think you will find most meters have a +/- 15% error so bear that in mind
 
Hi Kali
I'm going to second what all the other peeps have said.
It would be more helpful to know what your HBA1c level is, I'd go back to your GP and ask him to explain what you were being tested for and what the results mean. I can well understand you feeling very confused given those results. If you don't feel comfortable going back to that particular GP, make an appointment to see someone else, but this does need clarifying especially before beginning any medication.
Do, please, let us know how you get on.
 
Hi all Thanks for your comment. I now have the confidence to ask the right questions for the review of the tests. I. Will go for HBA1c. And keep you informed of the clarifications. Kali
 
Just one other question.

I noticed that for my blood glucose the doctor had the serum tested but not the plasma.

Does that make any difference?
 
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