Metformin and B12 Levels

[FancyPants54]

My husband takes Metformin. He has just been for his review and I badgered him to ask if his B12 had been tested and if so, what the level was. I didn't think he'd ask. He's very resistant to doing things like that. But he did.

He's been on Metformin since lockdown.

His level of B12 today is "fine" according to the GP. In fact it's 300. And as far as I'm concerned that's worryingly low.

How should we best treat this? I am thinking B12 drops perhaps but not sure of the frequency I should advise.

I'm about to start SI B12 myself, so I could inject him too if he'd let me. But that might be over-kill for this level and probable reason?

Any advice would be appreciated. Don't tell me to get him to get anything else tested because he won't. We only found out he's diabetic because during the lockdown the surgery rang and said that they hadn't seen him for 15 years and would be mind popping in for his BP to be tested!

[Nackapan]

Why not have a daily b12 oral supplement.My husband has type 1 diabetes and had his b12 tested added to his routine bloods after I got ill on my request.

His was 180! ( 200-900)

Deemed normal no advice.

He had no symptoms of b12 deficiency.

He however agreed to take one 10mcg b12 supplement a day.

Yes 10 mcg.

To my suprise his next blood test.

His b12 was 358.

He continues with the daily b12 .

We both have a very good diet .

So for him his absorbtiin just slowed down.

[Technoid]

If there are no noticeable symptoms I wouldn't go to injections right away. A low dose supplement of around 25 to 100mcg should be ok if there are no absorption issues. If low stomach acid, and/or absorption issues are suspected then 500 to 1000mcg would be more appropriate.

ref:

"What is an adequate dose of oral vitamin B12 in older people with poor vitamin B12 status? "

pubmed.ncbi.nlm.nih.gov/169...

[Gambit62 Administrator]

3000 may be perfectly fine for your husband - if he'd had an early serum B12 measure that was more than 20% higher that would indicate an absorption problem. Unfortunately you can't really tell much from a single test result.

If he is symptomatic then try following the advice given by Technoid.

Unfortunately though the symptoms of B12 deficiency overlap with a number of other conditions including conditions for which metformin is prescribed such as diabetes. You could try speaking to a pharmacist about alternatives to metformin if it doesn't seem to be resolving issues that caused it to be prescribed in the first place.

[FancyPants54 in reply to Gambit62]

Metformin controls his blood sugars well. He's happy with it for that job.

[Littlelodge123]

in the absence of any symptoms I personally would not do anything. 300 is not low.

[FancyPants54 in reply to Littlelodge123]

The B12 specialists say anything below 500 is too low.

[Littlelodge123 in reply to FancyPants54]

What specialists? There is no evidence for that claim at all except a few people on here who trot that rubbish out as if it is true!

[Technoid in reply to Littlelodge123]

What is considered low varies from country to country. It seems to be true that in Japan, anything under 500 pg/ml is considered low.

Take this excerpt from a research paper from Japanese researchers for example:

"The serum VB12 concentration in all the patients was within normal limits, i.e. 500-1,300 pg/ml. "

pubmed.ncbi.nlm.nih.gov/339...

However, most western countries have a much lower threshold, with the cut-off forwhat is considered too low often being around 160-210 pg/ml.

However, these cut-offs are cut-offs applied to a result (serum B12) which cannot really be relied on to exclude deficiency so IMO they are of limited usefulness.

[FancyPants54 in reply to Littlelodge123]

Don't be defensive. I'm pretty sure Sally Pacholock says that.

[palmier]

A calcium supplement can help people on metformin to absorb b12 better: pubmed.ncbi.nlm.nih.gov/109...

A b12 supplement is a good idea. No reason to wait until deficient, better to prevent. Both diabetes and b12 deficiency can cause neuropathy, which is best to avoid.

[clivealive Forum Support]

Decreased vitamin B12 levels are a known consequence of long-term treatment with metformin. The mechanism is currently thought to be multifactorial, comprising altered intestinal motility, bacterial overgrowth, and reduced uptake of vitamin B12 within the small intestine (or a combination of these factors).20 Jun 2022

Metformin and reduced vitamin B12 levels - GOV.UK

gov.uk › Drug Safety Update

I've been on Merformin for diabetes since 2015 bur as I've has P.A for over 50 years and have B12 injected it has not affected me.

I wish you and your husband well

[FancyPants54 in reply to clivealive]

Thank you. We have chosen a Vitamin B Complex with a good dose of B12 in it. And will give that a try. He feels well on the Metformin.

[bookish]

Whilst I would agree that 300 may be normal for your husband and that not everyone will have identifiable B12 deficiency symptoms at that level (or even lower), some can have symptoms at much higher levels. But as your husband has diabetes, it may be that he does have B12 deficiency symptoms, because that could be a symptom - see

Vitamin B12 and diabetes risk—myth or reality link.springer.com/article/1...

quote

'A very recent study confirmed that vitamin B12 supplementation regulates several diabetes-associated genes such as TCF7L2, FTO, and CREBP/CBP through methylation of MiR21 and could thus epigenetically influence the risk of obesity, insulin resistance, and type 2 diabetes mellitus [12].'

More research is needed, but the possibility that lack of B12 ( indeed any problem with one-carbon cycle function) increases risk of expressing epigenetic vulnerabilities, in this case for diabetes, is being considered. Dr Chandy has long considered that to be the case for autoimmunity.

Best wishes