This thread has so much useful information. I have posted twice under different categories about my medical issues, but I'm hoping Mrs. D or someone will see this here. My B-12 level is 373. Since February I have experienced numbness and tingling. It started in feet and hands but has progressed to other areas. It is constant and unrelenting. I have no other symptoms. I had a normal nerve conduction test in my legs. I have an MRI of my brain on Monday as my doctor is suspecting MS? She completely dismissed my B-12 level as normal. I have read enough to know that it is on the low end so I have begun to supplement. A friend of mine is a compounding pharmacist and she really thinks my symptoms may be from the B-12 levels. I guess I just wonder if anyone agrees with her? Holding out some hope that it may be the case. I suppose I will have more answers after the MRI. Thanks for listening.