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Blood donations

steph81170

Well-Known Member
Messages
93
Type of diabetes
Prediabetes
Does anyone have thoughts on this, please:
Two hours after giving blood recently I tested my blood sugar level and found them to be high (for me) at 7.8 - I am normally in the mid fives. I am not diabetic but 2 years ago was told I was pre-diabetic, changed my way of eating to low-carb, high (healthy) fat and my levels dropped to within the normal range and have stayed there ever since. I am 69 and weigh 50.5Kg. I do not take any medication. So why was there such a big jump on that day?
Any ideas would be appreciated!
 
Just musings here, less blood = higher concentrations? Blood loss perceived by the body as injury? Immediate response to replace that blood loss? Interesting question, indeed.
 
Guzzler said:
Just musings here, less blood = higher concentrations? Blood loss perceived by the body as injury? Immediate response to replace that blood loss? Interesting question, indeed.
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Yes, I think you are right in your musings - I can't think of any other explanation. Thanks for your reply!
 
steph81170 said:
Yes, I think you are right in your musings - I can't think of any other explanation. Thanks for your reply!
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I could be totally off the mark, we should wait for those who have gone into this subject in more depth. Thanks for posting.
 
An HbA1c test taken within a couple of months of a blood donation will be inaccurate as glycated cell will be replaced by new ones.
 
Mr_Pot said:
An HbA1c test taken within a couple of months of a blood donation will be inaccurate as glycated cell will be replaced by new ones.
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So by that do you mean a higher than usual reading?
 
As this thread is posted in a general sub-forum, a note for someone coming across this thread when searching for information in the future.
If your diabetes is treated with insulin, it is not possible to give blood in the UK.
 
@steph81170 - It could be the drop in blood volume. Your body reacting to the "trauma" and "heavy bleeding" of the donation, or all sorts. Sometimes our bodies send us little puzzles.

Test on for a few days and provided it all reverts to your usual ranges, just shrug and move on.
 
steph81170 said:
So by that do you mean a higher than usual reading?
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It will be lower than it would have been without the donation. I have no idea by how much, it may well be insignificant unless close to the HbA1c test.
 
steph81170 said:
So by that do you mean a higher than usual reading?
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No. It will be a lower reading because a pint (?) of the glycated blood has been removed. This will be replaced by brand new blood, untouched by sugar! I once saw an American forum where people were deliberately donating blood then having their HbA1c soon after.

Finger pricking is capillary blood and 2 hours after donating is unlikely to be changed in any way.
I suggest the general stress, anxiety, whatever, caused it. Or just a one off blip.
 
Bluetit1802 said:
I once saw an American forum where people were deliberately donating blood then having their HbA1c soon after.
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I suppose they should ask you if you have donated blood recently when you have a blood test but I don't think they do. If you had a transfusion that would also reduce your BG but it would be drastic unless you needed it anyway.
 
Yes, I think you're right about both "trauma" and "little puzzles" !!
 
That's interesting - thank you for the info. and I think that you are right about the stress etc ( in my case, not related to giving blood). Have just received my results of blood test taken before I gave blood - HBA1C 41 (normal for me) Trigs. 1.4 and Cholesterol 8.1 (high, I know but then it always is . . . . ) What do you think of these - should I be concerned?
 

Did you fast for this test?

What was your HDL and your LDL?

What were you on your previous test?

Are you in the middle of losing weight?
 
That's very interesting as I too donated blood last week and ever since have had much higher levels than normal, particularly my morning levels...even though my diet has not changed since. I have been confused as to why, but perhaps it is linked to donating blood after all.
 
Hmm - my levels have not yet come back down, even after four days! It is odd.
 
Bluetit1802 said:
Did you fast for this test?

What was your HDL and your LDL?

What were you on your previous test?

Are you in the middle of losing weight?
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I need to ask the surgery what my HDL and LDL levels are and check what the previous results were, so will come back to you if that's OK. I'm not in the middle of losing weight, I've been stable at 50.5Kg for about 18 months.
 
steph81170 said:
I need to ask the surgery what my HDL and LDL levels are and check what the previous results were, so will come back to you if that's OK. I'm not in the middle of losing weight, I've been stable at 50.5Kg for about 18 months.
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The best way is to ring and ask for a print out. The receptionist should be able to help you. You can also ask for a print out of the previous results. If you are in England you could also ask if your surgery puts test results on line as they are supposed to do, and how to register for this service.
 
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