30 y/o male, sick for 14 months now with a myriad of symptoms. Have been seen in all the major Boston hospitals by 35+ specialists...etc. etc. Wont go in to full story or all the testing and results here, but in regards to B12. I do have many of the symptoms of B12 deficiency. However when tested serum levels are always mid-range (usually around 500), MMA is always low but homocysteine is always slightly raised (around 15 range 0-12). MTFHR I am only 1298AC the heterozygous, NO 677. With these findings and my symptoms/lack of firm diagnosis I was able to get my doc to order some other related labs. Here were the results of those: ANA: Neg Gastric Paritel Cell Ab: Neg Fasting Gastrin: 15 pg/mL Range: <101 RBC, HGB, HCT: always just at lowest level of "normal" or just below B12: 514 Range: 180-914 pg/mL B12 Binding Capacity: 480 'LOW' Range: 650-1340 pg/mL My question is, what do these indicate? Given the IF, fasting gastrin and gastric parietal ab's, PA is all but ruled out. However, the low b12 binding test results, if I understand things correctly, suggests that while I may be getting B12 from my diet, my body is not utilizing properly? with that said, I wonder why my MMA level is always fine? The ordering doc was doing it as more of a favor and has no idea what to make of the results.... he has offered to provide b12 injections to see if they help with any of my symptoms.