History of breast cancer here, so get my b12 level and others checked every 7 weeks. Now, I have read in some cancer fora supplementing with B-vitamins, in particular B12, can increase the risk of cancer, if ones level is always a bit high.I usually am around 5-700 nmol/L, when I get my Hydroxocobalamin inj., but naturally that shoots my level up for a while before it decreases during the next 7 weeks until next "refill"...
Question:
Am I increasing a cancer risk every time I get my new B12 load?
Do you know of the studies in question that I could read?
TIA🙏
Written by
indywindy
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I am on this forum every day since 2014 . I have never heard that high readings of B12 can cause cancer when one is supplementing . I only test for B12 once a year , privately . I have injected weekly since that date , and my B12 level is off the scale .
I've been having B12 injections every month for over 51 years for P.A and I think I'm right in saying that I am at an increased risk of stomach cancer from the cause of the P.A than the treatment.
I also think that it is mooted that some cancers can cause an elevated level of B12 in the blood but that is something different.
I am not medically trained but I am still "clivealive" at the age of 82.
I think that high levels of B12 have been found in some patients with cancer but that to my mind (I'm not a scientist or doctor) does not mean that high levels of B12 cause cancer.
Maybe something interesting in these articles below.
Treatment with high dose vitamin B12 been shown to be safe for more than 50 years
The problem is causation vs association. As mentioned by Clive, some cancers can cause elevated B12 levels in and of themselves. And some people with Cancer may take high dose B12 supplements or injections. So one must also be careful of reverse causality.
There have been several previous threads on this which may be worth reading through, see the "related posts" on the right.
Hi, it has been scientifically proven that Vitamin B12 supplementation significantly increases the risk of developing cancer, especially oesophageal and lung cancer. I was diagnosed with thyroid cancer 5 years ago and wit PA 3 years ago, my endocrinologist who is professor and lecturer is not happy about my B12 injection despite the fact that I suffered from neurological symptoms, therefore I try to space them as rarely as possible 8-12 weeks. On the other hand B12 deficiency can also increase the risk of other cancer.
Maybe, you couldn't find it, so here it is cpy/pasted:...Thank you everyone very much for this and for taking the time🙏.
I am still confused, though...Like Blackmarker said, they have been claiming this in my other cancer fora. So I googled a bit to find the studies, that could claim the connection...
Maybe this could be one of them:
Conclusion:
.....as well as previously published studies, 4,5, these findings support the hypothesis that higher circulating vitamin B12 concentrations increase the risk of lung cancer.
ncbi.nlm.nih.gov/pmc/articl...
Cancer
....Studies are mixed on whether vitamin B12 in combination with folate and B6 can reduce cancer risk, and it may increase risk of lung or colorectal cancers. Additional studies are needed to determine how vitamin B12 levels may affect cancer risk....
mskcc.org/cancer-care/integ...
And this from 2017:
...Risk was further elevated in male smokers taking more than 20 milligrams of B6 or 55 micrograms of B12 a day for 10 years....
...“Our data shows that taking high doses of B6 and B12 over a very long period of time could contribute to lung cancer incidence rates in male smokers. This is certainly a concern worthy of further evaluation.”
This is commonly misunderstood. High B12 level without supplementing can be a sign of cancer. But supplementing to get B12 levels high does not cause cancer.
Im also interested to hear what our other members know. I read high B12 can cause bone fractures too? But then life without B12 injections is unbearable 🤷♀️
Baklava22 the video from Nutrition Facts below covers those studies.It's Important to be aware that B12 deficiency likely impacts Taurine production which in turn negatively affects bone health.
No it shouldn't be an issue once you have been adequately treating a B12 deficiency for some time. Taurine is not an essential nutrient but I find the preliminary evidence of benefit promising and no evidence of harm at dosages of 500mg to 1 gram.
I think in general the influence of MTHFR is massively overrated and serves to prop up a mini industry of "methylation" "experts" who are eager to sell tests of questionable value and supplements which have pretty skimpy physiological evidence of their necessity or effectiveness.
We are all entitled to our own opnions, but I have read many methylation studies by now, and am in related online communites, that I share the same challenges with, and ways to avoid. It has really helped me to know how navigate my many symptoms with following challenged pathways.
Many MTHFR communities can be a source of abundant misinformation on MTHFR.
Here are some useful resources. Reading just one or two should be enough to give you the general gist which is that genetics experts do not see value in most of the tests and supplements promoted by these communities and alternative health practitioners.
Some useful resources
America College of Medical Genetics and Genomics - ACMG Practice Guideline: lack of evidence for MTHFR polymorphism testing (2013)
Thank you everyone very much for this and for taking the time🙏.
I am still confused, though...Like Blackmarker said, they have been claiming this in my other cancer fora. So I googled a bit to find the studies, that could claim the connection...
Maybe this could be one of them:
Conclusion:
.....as well as previously published studies, 4,5, these findings support the hypothesis that higher circulating vitamin B12 concentrations increase the risk of lung cancer.
....Studies are mixed on whether vitamin B12 in combination with folate and B6 can reduce cancer risk, and it may increase risk of lung or colorectal cancers. Additional studies are needed to determine how vitamin B12 levels may affect cancer risk....
...Risk was further elevated in male smokers taking more than 20 milligrams of B6 or 55 micrograms of B12 a day for 10 years....
...“Our data shows that taking high doses of B6 and B12 over a very long period of time could contribute to lung cancer incidence rates in male smokers. This is certainly a concern worthy of further evaluation.”
Hi inidywindy. The phrase 'increase the risk' doesn't actually mean a causal relationship. It means that statistically there is a higher chance that someone with high circulating b12 will develop cancer, ie it identifies a 'correlation' or an association as Technoid called it. The causal mechanism may be related to the reason for higher circulating B12 - eg B12 plays a role in replication of DNA so a deficiency is likely to increase the risk.
Having PA trips one mechanism that can lead to the development of colon cancers but the risks (statistical chance) without PA and even with PA are still very, very small.
OK. So at best we have a hypothesis. And even here we have the old problem of association is not proof of causation. If there were proof would not the b12 ampoules have to detail the risk as with other medication?
I have not read this whole thread but my “two cents worth” is that so many things, known and unknown can trigger cancer. Environmental and chemical triggers are insidious. If you live your life in fear of cancer you cannot live. I try to avoid carcinogens. For nearly a decade now I drink almost exclusively from a glass with a glass lid/straw as plastics give me reactions. I just read an article about the safest drinking vessels. Glass is considered better than many options but was not recommended because of boron silicate. The recommendation was stainless steel. Been there, done that. I was told by a doctor that even stainless steel has its hazards. What is my choice? I am sticking with glass.
The point is almost everything including “healthy food” has its risk. If you need vitamin B12, the benefit almost unequivocally outweighs the risk. We live in a pretty toxic world.
I don’t know how many places you read this but I doubt that this information is known or can be substantiated by many.
I live every day in fear because I am so sick. I have to make choices over risk/benefit many times a day. I make all accommodations I can to avoid risk, but I have to eat, breathe, etc. so inevitably it comes down to choice.
If your gut says/knows you need B12, then you should probably listen to it. You are not choosing to smoke, drink or use substances known to cause disease.
I would try to let this go.
Sorry if this felt like a lecture. Maybe you can feel the struggle I, myself, have weighing choices when really sick. It looms over me every day
Two points not reported here are first: Per Consumer Lab.org, there is a risk from high vitamin intake only when it it is used with supplemental folic acid. The increased risk there is for colon cancer for sure, but they could have stated more types too but I focused only colon since I had dangerous polyps found.
Second, if you already have a cancer of some sort someplace, adequate B blood levels can be blocked from use by the biological action of your cancer's nature and its effect in your body. It is not common but it happens.
I may have that condition since I do have prostate cancer which is slowly worsening, and have adequate B levels as indicated by all the right tests, but still had many B deficiency symptoms.......low platelet problems, macrocytosis, (oversized red blood cells), red feet, tiredness, feeling very ill & others. After supplementing with high B and B complex my platelets, macrocytosis & other symptoms have improved over time and I also now feel normal.
I know this is a reply to you mick33w but this is largely to address blackmarkers claim that b12 supplementation increases the risk of developing cancer.
The strongest study referenced is the "B-Proof" trial, a randomized controlled trial on vitamin-B12 and folic acid supplementation on fracture risk. Oliai Araghi et al conducted a secondary analyses on cancer incidence within this trial. The study reported "a higher risk of colorectal cancer among those allocated to folic acid and vitamin B12 compared with placebo, which persisted over time (6–9 years). This was observed in older ambulant persons with mildly elevated homocysteine concentrations"
Concluding with:
" To clarify the role of combined supplementation with B vitamins on colorectal cancer, further confirmation, for example by individual meta-analyses of existing, large RCT of folic acid and vitamin B12, with additional information on the presence of early neoplastic lesions in the colorectal mucosa, is needed."
The elevated homocysteine of participants in the trial is notable because high homocysteine is a potential contributor to colorectal cancer development. ref : ncbi.nlm.nih.gov/pmc/articl...
Although the finding is worth taking seriously it is just a single RCT and as such does not "prove" that Vitamin B12 supplementation increases the risk of incidence of colorectal cancer. In fact, because folic acid was also used, it would be impossible to disentangle the two. As they state in their own conclusion, a meta analysis of large scale RCT's for folic acid and B12 (preferably individually) would be needed to support such a conclusion.
Single studies do not prove things - their findings need to be investigated and replicated in other studies and ultimately confirmed in well-conducted meta-analyses of RCT's. Speaking of which, a meta-analysis of RCT's on this issue in 2016 found that:
"Vitamin B supplementation does not have an effect on cancer incidence, death due to cancer, or total mortality. It is associated with a lower risk of skin melanoma, but has no effect on other cancers."
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