My B12 is 544 ng/L. Is that an OK level? The private doc is willing to give me shot of B12 and says some people need more than the norm. Can you have too much B12?
I asked for Active B12 as I had read that the NHS test is not thorough enough, but he said there is only one type of test. So now I am confused.
Thanks.
zepo
I asked for Active B12 as I had read that the NHS test is not thorough enough, but he said there is only one type of test
Maybe there's only one type of test he can obtain. There is Serum B12 and there is Active B12.
My B12 is 544 ng/L. Is that an OK level?
It's not bad. According an extract from the book, "Could it be B12?" by Sally M. Pacholok:
"We believe that the 'normal' serum B12 threshold needs to be raised from 200 pg/ml to at least 450 pg/ml because deficiencies begin to appear in the cerebrospinal fluid below 550".
"For brain and nervous system health and prevention of disease in older adults, serum B12 levels should be maintained near or above 1000 pg/ml."
ng/L is the same as pg/ml so these levels apply to your result.
Excess B12 is excreted.
Depending on the cost of the B12 injection, I expect sublingual methylcobalamin lozenges would be just as good, just make sure you balance all the B vitamins by taking a good B Complex as well.
I find I can't tolerate B vits in my old age. I used to take lots when younger, but now, especially B6, I find that my Bruxism is worse! I even have to avoid food with added B6.
Had my B12 tested last week; first time in years. I take sublingual adenosylcobalamin, 5000 mcg, once per week(my own protocol). It's a form of B12 important for mitochondrial function. Daily B12 causes too much of an increase in histamine, along with worsening sleep, which is already bad. Serum B12 was 1000.
tropicaldaze Thanks. I didn't realise B12 can affect sleep. I do take sublingual tabs intermittently. Some nights my sleep is worse than others, so I will see if it coincides with when I take it. I hadn't thought about that. Mitochondrial - hmm - maybe more B12 will help my OCD then.
B vitamins can be stimulating so it's advised to take them no later than lunchtime.
yes it seems that way. Seaside Susie. I used to take a mega dose of B's in my 20's, but at 64 even lunch time is late and coffee is a total no go. 
I have Tourette's Syndrome, in addition to treatment resistant bipolar. As much as I want to load up on daily B12, the increase in histamine makes my tics worse, makes me irritable and moderately manic. That's why I settled on a once weekly dose. I recall when I was 22, I was feeling depressed and exhausted. My doctor, an endocrinologist, gave me a B12 shot. The most surprising aspect was that my libido went even higher! He explained that it's histamine that ramped it up.
There's a biochemist at Oxford, Dr. Carmen Wheatley, who is one of the world's experts on B12. I read one of her papers on PubMed(though I understood about a third, LOL) and in that paper, she discussed adenosylcobalamin as important for mitochondrial function and the production of endothelial nitric oxide, which dilates blood vessels.
tropicaldaze - I always think Tourettes and OCD are related, so maybe too much would worsen OCD I will watch out for that. Libido haha I have forgotten what that is. lol
I've had mild to moderate OCD since I was a child, which is when TS began. I have a lifetime history of psychological/psychiatric problems.
Sorry to hear that. OCD is a curse - ruined my life. I did read that underactive thyroid can affect (or even cause) OCD and mental health. So my reason here is two fold - OCD and just feeling plain crap all the time. Best wishes.
Are you on thyroid medication? Ever had a full hormone panel; testosterone, estrogen/estradiol, progesterone, DHEA, prolactin, DHT, SHBG? Regarding thyroid, if one is hypopituitary, a much higher dose of thyroid(T3 or dessicated) needs to be achieved in order to compensate for a malfunctioning pituitary.
No meds at the moment. Just looking into it all. I think I had a full hormone panel some years ago and it was OK. Just about to do a thyroid one. I've not even heard of hypopituitary. Just when I was struggling to understand thyroid stuff and now there's more!
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