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High RBC and B12

gracee41

Senior Member
Messages
115
Sure hope someone can give me their insight. As I've posted previously, my B12 level is very high (greater than 2000). I developed many symptoms of a B12 deficiency and took methyl B12 for several months. I felt better but my level never dropped. I do have MTHFR and hypothyroidism.

Recently I had to reduce my thyroid med and add in straight T3 as my body wasn't converting the T4 to T3. I've had lab work several times since then and now my RBC, hemoglobin, and hemotacrit is elevated. With these levels being elevated along with my B12 level being so high, my doctor referred me to a hematologist. I've had a homocysteine test twice, a MMA serum test, and waiting on the results of an MMA urine test. The former two were normal. My MCV and MCH is normal as well along with my other CBC levels including my WBC.

I know B12 is needed for the thyroid to function properly. If I had anemia from a B12 deficiency, my RBC, hemoglobin, and hematocrit should be low. I am at a loss as to what is going on or how to fix it, especially the B12 level. I can say that my RBC, hemoglobin, and hematocrit have only gone up since I dropped my thyroid med and added T3. Research states that HYPERthyrodism can cause this. I am still hypo and not hyper per lab results. I feel the high B12 levels and other high levels are connected in some way. Does anyone have a clue what might be happening?
 

JES

Senior Member
Messages
1,320
I would say in most cases the blood level of B12 will increase after supplementation, no matter if you are deficient or not. There would still be a surplus of B12 in blood from the supplement, so this would be expected. IMO blood levels are useless to measure if you are supplementing, the only way to get a reliable reading would be to stop supplementation before the test. So I wouldn't be worried about a high B12 reading while on a supplement.

To me it doesn't sound like you have any kind of B12 deficiency (bear in mind CFS/ME patients can still improve on B12 despite no clinical deficiency). Too high RBC count can simply be caused by dehydration, or it can be a more serious condition like polycythemia, but this is not a common illness. Never heard it could be caused by hyper/hypothyroidism, but who knows.
 

gracee41

Senior Member
Messages
115
I would say in most cases the blood level of B12 will increase after supplementation, no matter if you are deficient or not. There would still be a surplus of B12 in blood from the supplement, so this would be expected. IMO blood levels are useless to measure if you are supplementing, the only way to get a reliable reading would be to stop supplementation before the test. So I wouldn't be worried about a high B12 reading while on a supplement.

To me it doesn't sound like you have any kind of B12 deficiency (bear in mind CFS/ME patients can still improve on B12 despite no clinical deficiency). Too high RBC count can simply be caused by dehydration, or it can be a more serious condition like polycythemia, but this is not a common illness. Never heard it could be caused by hyper/hypothyroidism, but who knows.
Thank you for your reply JE S. I actually had the high B12 level before I started supplementing. It didn't change after supplementing even though I thought I probably had a functional deficiency at the time based on my symptoms at the time. I just wonder why it's so high. It was normal 2 yrs ago. This has me very concerned especially with my RBC, hemoglobin, and hemocratic. At least my WBC count is normal.