Blunted or impeded therapeutic response to vitamin B12 may be due to such conditions as infection, uremia, drugs having bone marrow suppressant properties such as chloramphenicol, and concurrent iron or folic acid deficiency
Vegetarians and Vegans Because B12 is primarily found in animal-based foodssuch as meat, eggs, poultry, and dairyvegetarians and especially vegans are at high risk for deficiency
So, you measure a higher B12, but part of that B12 is inactive, so useless Oral B12 supplementation, even in the form of a multivitamin preparation, may result in serum B12 concentrations just within the normal range without abolishing symptoms
Maintained Testicular Function Because hCG mimics LH, it maintains testicular size and function, including sperm production