Any ideas please if levels of Active B12 can increase way beyond the recommended Medichecks range of (37.5 - 187.5) just by increasing dose?

Hi All

Still looking for an answer for muscle aches!

My last 5 Active B12 Medichecks readings (roughly every 4 months starting from Feb 19) are

Feb 19 - 200

May 19 - 195

Aug 19 - 235

Jan 20 - 150

July 20 - 180

Ranges are the same for all the above - (37.5 - 187.5)

All achieved with 10 ug B12 a day, which I have been taking for over 30 years now

My Medichecks liver and kidney results have always been in range

I understand that since B12 is water soluble, any excess is excreted?

So, the Active B12 range cannot increase much more than my current high or over range numbers?

So, as an experiment to see if it helps with the aches, I am planning to increase to 20 ug a day for a week and see how it goes.

Any views greatly appreciated!

Thank you

Alps

[fbirder]

There are a couple of reasons why I think you will be disappointed.

Firstly, muscle aches alone are not really a symptom of a B12 deficiency. So it's unlikely it is the cause of your problems. Secondly, your blood levels are already much higher than normal and almost certainly have been for 30 years. So it looks as if a lot of B12 hasn't made much difference.

Taking 20 mcg a day will probably not make much difference to your B12 levels. Not because your blood can only hold a certain amount, but because you're unlikely to absorb much more than you are now.

The absorption of B12 from the gut has a limited capacity of about 10 mcg at a time. So you are probably absorbing most of your 10 mcg tablet. But it cannot possibly absorb all of a 20 mcg dose. So the amount you absorb will not increase by much.

And the amount that you eliminate in the urine is dependent on the amount in the blood. So, if you do absorb any more B12, most of it is likely to be rapidly eliminated.

[Hidden in reply to fbirder]

Thanks fbirder

For informative reply as usual

Am looking absoutely everywhere for an answer to the aches that started during a 12 week course of statins, ending in April 17.

However, depite stopping the statins over 3 years ago now, the aches have progressed.

So, I've tried this, that and the other many, many times, to no avail

Yes, I take your point that the body is unable to absorb any more than 10ug

One reason that my B12 levels are on the high/over range side may be because I take 10ug in 3 doses a day?

With Meals, I take 2.5ug, 2.5 ug, 5ug.

In my previous B12 post, somebody also suggested I test MMA and Homocysteine - is that useful?

Thanks

Alps

[fbirder in reply to Hidden]

Your B12 levels are so high because you're taking 4 times the RDA (plus whatever you eat in food).

Testing MMA and hCys would tell you if you're suffering from a functional deficiency (where there's lots of B12 in the blood, but it's not getting to the right places in the cell). But I'd bet that's not the case as it's fairly rare and it doesn't match the symptoms you're describing.

[Hidden in reply to fbirder]

Thanks fbirder for a logical answer, as usual

I shall discuss MMA and hCys with my very considerate GP

Is this done via a blood test please?

So that I can 'tick' off this particular box

I've had every test and nothing to show for it

As a lifelong cyclist, I find it really 'flattening' that I can't ride my bike at my pre-statin pace of 17 av.

But, I shall never stop looking for an answer!

Thanks again, you've always been helpful

Alps

[fbirder in reply to Hidden]

MMA can be done via a blood test or a urine test. The levels can be raised by things other that a B12 deficiency - like liver or kidney problems. The urine test allows them to check kidney function at the same time. But you've already eliminated that. So the blood test should be suitable.

hCys is also a blood test. But it's not simple as the assay has to be done within a very short time of the sample being taken. So it needs to be done at a hospital with its own pathology lab that has the equipment set up. I've only had it done once, at the National Hospital for Neurology and Neurosurgery.

[Hidden in reply to fbirder]

Thanks fbirder for an informative answer

Lots there I didn't know!

Will discuss with GP asap

He should know the local NHS labs that can do this

So, if the MMA and hCys results come back ok, that means my B12 question has been answered?

Thanks again much appreciated

Alps