Just Google: B12 and hematocrit and you will find a lot information

In patients who are deficient in B12, the CBC would show anemia, which manifests as a decrease in both hemoglobin and hematocrit. In addition, the mean corpuscular volume (MCV), which measures the size of red blood cells, would be increased to a level greater than 100.

Hi Joanne,

Do you have a good physician you can talk to about how the supplements you take could influence your blood count?

The study below shows that taking vitamin B12 can increase red blood cells production, but most likely every body reacts differently to supplements:
"During the 4-week observation period, vitamin B12 and folate enhanced erythropoietin-induced erythropoiesis significantly, as indicated by a 10% increase in red blood cell counts, compared with folate alone."
https://pubmed.ncbi.nlm.nih.gov/16818564/

This is a study in athletes regarding vitamin B12 injections and hemoglobin:
https://www.ncbi.nlm.nih.gov/pmc/articles/PMC72...

I know it is tough to keep track of everything our supplements contain, especially when what is written on the front of the bottle is just a part of what that supplement contains. I discovered my Omega 3 supplement had absurd amounts of vitamin A and vitamin E added, although the package & prescription said Omega 3. Magnesium supplement had 2000% of the daily recommended dose of vitamin B6, while the front label said simply Magnesium. This information was written in small script on the back of the bottle, and so on and so forth.

Best wishes,
Tatiana

Vitamin B12 Status and Optimal Range for Hemoglobin Formation in Elite Athletes

https://www.ncbi.nlm.nih.gov/pmc/articles/PMC7230602/

A randomized, controlled trial of the effects of adding vitamin B12 and folate to erythropoietin for the treatment of anemia of prematurity - PubMed

https://pubmed.ncbi.nlm.nih.gov/16818564/