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B12 plateau?

Hi all,

I have been on sublingual hydroxy b12 for the last 4 months (following a b12 deficiency diagnosis)... slowly increased it up to 2000mcg a day. My serum b12 was tested several times and gradually increased from 150's up to upper 400's on my way up to the 2000mcg. I've continued to take this daily dosage for the past 2 months and just had a recheck - the level seems to be at a plateau, as I have only gone up from 479 o 498 in these two months. What might be some causes for this? Thanks!


Senior Member
Hi, patteecreek.

I would say that either your cells are absorbing it, or the excess is being excreted in the urine. You posted that you don't have ME/CFS, so perhaps you don't have a functional B12 deficiency, and your cells are using the B12. You mentioned that you had not been eating meat for 20 years. You might have become very depleted in B12, so that your cells are still building up to normal levels.

Best regards,

Hi patteecreek,
A number of months ago you posted, ". About a month ago, I went to my doctor with symptoms of recurring canker sores, fatigue, foggy thinking, trouble concentrating, forgetfulness, anxiety, trouble focusing eyes at times, and increasing gut issues. She checked only my b12 and ferritin levels. My b12 tested at 205 and MMA 0.38, likely due to 20 years of vegetarian diet, and also being lactose intolerant"
Have your symptoms improved since then?
When I first found out that I was B12 deficient I started taking 1000mcg of cynoB12 per day. My B12 serum came up to approx 300 and stayed there, but my symptoms kept increasing. It wasn't until I found information on Freddd's protocol and started following it that many of my symptoms relieved. At that time I was taking 20mg or more of methyl B12 and many of the vitamins and minerals recommended by Freddd. My B12 serum level went off scale >2000.
Best regards,
Hi Mogy,
I'm happy to report that many of my symptoms have improved significantly. Those that haven't (fatigue and anxiety) may simply be due to current life circumstances. I was surprised (based on how much my symptoms improved) to find that my B12 was not continuing to rise. I am hoping that Rich is right in his thoughts that my cells may be utilizing the B12. Glad to hear that you've had success with Freddd's protocol. While I'm not sure it's the ideal route for me at this point, I do think you are right in the suggestion that I may need more vitamins and minerals in combination with my b12. I've been incorporating some for awhile, and am just beginning to add vitamin D and more omegas. Thanks for writing!