Higher Lung Cancer Risk Due to Vitamin B Supplementation?

[dng050]

Hi, all. I am MTHFR homozygote, trying to get my elevated homocysteine (>11) down by supplementing with vitamin B complex. However, I have come upon some research articles which show an association between vitamin B supplementation and higher risk of lung cancer, e.g. this study:

Cancer Incidence and Mortality After Treatment With Folic Acid and Vitamin B12 (https://jamanetwork.com/journals/jama/f ... cle/184898)

Anyone taking vitamin B complex who has dealt with this issue before?

[BrianR]

I believe other studies have shown that supplementation with Folic Acid can increase cancer risk. However, supplementation with Folate does not.

[NF52]

Hi, all. I am MTHFR homozygote, trying to get my elevated homocysteine (>11) down by supplementing with vitamin B complex. However, I have come upon some research articles which show an association between vitamin B supplementation and higher risk of lung cancer, e.g. this study:

Cancer Incidence and Mortality After Treatment With Folic Acid and Vitamin B12 (https://jamanetwork.com/journals/jama/f ... cle/184898)

Anyone taking vitamin B complex who has dealt with this issue before?

The two original studies were of Norwegian residents with heart disease, as indicated in the Clinical Trial.gov description of a planned long-term follow-up:

All patients in NORVIT were randomised following an acute myocardial infarction, whereas patients in WENBIT were randomised following coronary angiography, of which 85% had stable angina pectoris, 10% had acute myocardial infarction and 5% had unstable angina pectoris at baseline.

https://clinicaltrials.gov/ct2/show/NCT00671346

If you haven't had a heart attack or angina, the reported link with a risk of lung cancer may not be applicable to you. (It's also not clear that the researchers reported or accounted for smoking history in this work done between 1998-2005. This is a factor more commonly included now in clinical research.) You may want to try using a targeted approach to B-12 using methylcobalmin, not the cyanocobalamin commonly used in B-12. I was advised during a clinical trial to supplement, specifically with methycobalamin and sat quick results. My folate always tested in the normal range, and I tend to hold onto iron, so don't use a folate or folic acid supplement.

[dng050]

I have found this B vitamin complex, which I consider taking:
https://www.med24.no/vitaminer-minerale ... ve-120-kap

The label says (in Norwegian) it contains "Folsyre (calcium-L-methylfolat)". "Folsyre" is folic acid, directly translated to English. But from what I understand, calcium-L-methylfolate is actually a form of folate and not folic acid. Is that correct?

Hopefully, I would not need to take the B vitamins for years, as was done in the mentioned trial where the increased risk of lung cancer was found.