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The MTHFR gene mutation may make your body less efficient at converting folic acid and folate into L-methylfolate, the active form of folate in the body. People with this mutation may also be more likely to be deficient in vitamin B-12. Although certain forms of B vitamins are sometimes promoted for people with this mutation, they may not be necessary. For more about this, see the What to Consider When Using section of the B Vitamin Supplements Review.

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August 28, 2016

I was taking the cyanocobolamin form of B12 regularly, low dose. I had, across several years, severe lower leg and ankle pain, so bad at times that my ankles felt as if there was something very wrong physically. I spoke with doctors (MD) several times about this, with absolutely no help (interesting how different doctors approached it, I will say). Then my older daughter, having recently been tested for an MTHFR mutation, suggested I try the methylcobalamin type of B12, not for my leg pain specifically, just because it made her feel better. My chronic leg pain went away within an hour of taking 1000 mcg of methyl B12. I have difficulty finding words to express the change in the quality of my life this tiny supplement made. That event led me to look through the genetic testing of my younger daughter, who had been tested while pregnant; she has 2 MTHFR mutations. I have not spent the money to get tested. I take 1000 mcg of methylcobalamin each morning.
I will note that I went to a nurse practitioner for medical care, and told her about this. She ran blood tests, and told me to quit taking the B12, as my blood levels were high. I did not follow medical advice, nor did I try to explain that the test results did not necessarily mean I did not need the B12 (methylation and B vitamins is brain-warpingly complicated).
For awhile, I also supplemented with 25 mg P5P (methyl form of pyridoxin, or B6) and a methyl form of folate; the lowest dose I could find is 400 mcg, which I concluded is too much. Now I take a tablespoon of brewer's yeast and one 1000 mcg tablet of B12.
I also use a variety of supplements for vein, eye, bone, and joint health.
I check out the research, and make educated choices.
Obviously, I believe there is a place for the judicious use of supplements. Otherwise, why would I belong to Consumer Lab?

August 29, 2016


Elizabeth 11212
August 30, 2016

Thank you for sharing!!

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