Blood Test results - Please Advise... - Pernicious Anaemi...

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Blood Test results - Please Advise...



I had a blood test at my GP surgery in September and my results were:

Serum B12 level:

119 ng/L (150-900)

Serum Folate level:

2.3 ug/L (3.1-19.9)

I did a thriva blood test after supplementing 5mg folic acid for 4 weeks and 1000mcg Jarrows B12 for 3 weeks and my results are:

Total B12:

352 pmol/L (Normal 300-569)

Active B12 Level:

118 pmol/L (Normal 37.5-188)

Folate :

36.6 nmol/L (Normal 8.83-40) (Optimal 40-60.8)

I’m very confused because they are in different units to the tests at my doctors! Have they improved? How do I work it out? Also I tested negative for the intrinsic factor before supplementing. Is it likely I don’t have PA as I have been absorbing from the supplements?

Any advice appreciated!!

15 Replies

The different units are because one is using the weight of the thing being measured and the other is using the number of molecules of the thing. It's like buying apples, A can buy a dozen apples or I can buy 1.2 kg of apples. I still have the same number of apples, but the amount is described in different ways.

A mole of something is just the number of something. Like a dozen apples is 12 apples, or a score is 20 apples, or a gross is 144 apples. A mole of apples is 602,000,000,000,000,000,000,000 apples.

With apples we can say that the have a dozenal weight of 1.2 kg per dozen. With the B12 molecule we can say that it has a molar weight of 1.35 kg per mole. Folic acid is a small molecule, so it has a molar weight of 0.44 kg per mole.

So your B12 of 119 ng/L converts to 88 pmol/L

Oh wow, so it has improved quite a lot with the supplements to 352?

It may have.

I had to finish my post early (two greyhounds insisting that it was time for walkies).

What is important is how your number relates to the 'normal' range. Your original serum B12 was obviously quite a way below normal. Your Thriva blood test has the serum result just above the bottom of normal, but your active B12 is way above normal. That's a bit strange, you would expect both of them to have risen equally.

What's more important is - have your symptoms improved?

The only symptom I have are hairloss and oily skin. I’m not sure I can blame the b12/folate for those though I don’t think they are typical symptoms??


Sarah - how did you get on with 5 mg folic acid? Did you have any reaction to it?

Sarahlouise1980 in reply to Hidden

No, not to the folic acid. Why?

Hidden in reply to Sarahlouise1980

I had dreadful insomnia and anxiety for three days. Only took three doses. Did take a mega dose of B12 with first dose so it may have been that. It seems that 5 mg Folic Acid is a bit high for some people and such side effects while not common are not unknown.

Tried one again today in case it was B12.

GinGlass in reply to Hidden

Are you sure it wasn't b12? I had to take 5mg folate for 4 months, but no side effects - I felt so much better in every way. However, first 2 days of taking b12 made me depressed and sleepless. It passed though, as quickly as it came.

Hidden in reply to GinGlass

Funny you should say that GinGlass. Yesterday I thought again about the B12 and decided to have another go with the 5 mg Folic Acid. No problems. I must say that the B12 dose was a bit hefty. 3000 mcg 😩. Thanks for your thought. Got to get this Folate up into range.

GinGlass If you don’t mind me asking- Did you get your folic acid on prescription or buy it? The doctor gave me one months worth on prescription but now I can only find much smaller doses in the chemist?

You can only get the 5000 mcg tablets on prescription because they are harmful. 400 mcg a day should be plenty (especially if you eat a sensible diet) and some say that 1000 mcg a day should be the absolute maximum.

It was on prescription, only 1 month at a time, but on repeat 'til 4mths were up (and the 4mths was as per the nhs guidelines to treat da deficiency,). I've looked since and even in Holland & barrett, you cant get such a large dose over the counter.

So are you on a lower dose now or did you just stop after the four months?

I stopped.. I was worried as it had made me so much better, but blood test 3 weeks after stopping showed levels still 19, so leaving for now and blood test again late this week. Interestingly, I started b12 spray 2 weeks after stopping folate and that seemed to help my hand pins & needles etc, which had started to return.

get shots immediately--mine level was 211 and I took a shot weekly for one year--still had nerve damage and muscle damage but I'm 70% better than I was.

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