2 âVitaminsâ to Avoid - and What to Look For: Choosing a Multi-vitamin or Prenatal
Hint: Donât rely on the very low standards of the FDA in this important decision!
#1 âVITAMINâ TO AVOID:
Contrary to what you might have heard, folic acid is NOT the same thing as naturally occurring folate.
Naturally occurring folate, known as vitamin B9, is found abundantly in green leafy vegetables (foliage) and other plant foods. Folate is the cornerstone for a process called methylation, affecting over 200 cellular functions in the body, including:
synthesizing and maintaining DNA and RNA
production of ATP (energy)
neurotransmission (mental function)
preventing congenital heart defects
preventing neural tube defects like cleft palate and spina bifida.
Folic acid, although a type of folate, is an imposter â a synthetic type of folate that closely resembles naturally occurring folate with the exception of a methyl group, and this is important. This lack of a methyl group requires additional âprocessingâ done only in the liver, using special enzymes from folate pathway genes. Folic acid is not useful until it is transformed in this pathway. Humans have this pathway, but the story isnât that simple.
If youâre a rat, transformation of folic acid is rapid because rats have a high ability to convert folic acid, making it an effective rat supplementâŚyeah for the rats, but unfortunate for humans. We are only more recently understanding that human folate enzymes are much slower and only transform folic acid at a rate of 2% the rate of a rat. And it gets worseâŚ.
In the human liver, the folate pathway genes, known as DHFR and MTHFD1, are slowed by folic acid and go even slower in individuals with recessive genes in this region (up to 40% of the population has an MTHFR polymorphism). This floods the body with unmetabolized folic acid. Is this a problem? Yes. And this occurs at intake levels of 220 mcg â well below the RDA recommended intake of 400 mcg found in vitamin supplements. In the US, there is data that 43% of children <5 years old and 38% of the elderly have high levels of unmetabolized folic acid in their blood (>45nmol/L).
 Hereâs what unmetabolized folic acid does:
interferes with mental function,
increases insulin resistance
increases risk for certain cancers and
increases risk of autoimmunity other adverse health outcomes.
Even when folic acid is transformed, it still interferes with the folate pathway enzymes, contributing to clinically significant symptoms including, but not limited to:
altered lipid metabolism â high cholesterol
 In summary, folic acid can interfere with:
folate binding to receptors*
getting natural folates into the cell
blood levels of folate (lab results get skewed)
masking vitamin B12 deficiency
methylation of sperm (fertility)
 *This is similar to when carbon monoxide (instead of oxygen) binds to the hemoglobin molecule, causing suffocation. All kinds of cellular dysfunction occur when folic acid blocks active methylated folate from the receptors.
Folic acid is easy to commercially produce compared to the methylated version, and it seemed like a good idea to use it in 1998 when it was added to commercial flours, cereals, and other foodstuffs, including vitamins, to prevent birth defects like spina bifida. It turns out, however, that the slow transformation of folic acid in humans doesnât produce the active form of folate in the way we thought it would and promotes dangerous unmetabolized folic acid, as well as other negative health effects.
Nutritionists and doctors agree that folate supplementation is beneficial and crucial in pregnancy, but the type of folate matters.
Folic acid has unintended consequences, outlined above, and falls short as a safe and optimal folate supplement. It has a more limited ability to facilitate methylation and protect against neural tube defects, like spina bifida, in some individuals when compared to active folate. There are better options for everyone, especially those with genetic variations in MTHFR pathways.
Carriers of certain polymorphisms in genes related to folate metabolism or absorption can better benefit from 5-methylTHF instead of FA. 5-MethylTHF [also known as (6S)-5-methylTHF] is the predominant natural form that is readily available for transport and metabolism. (Obeid R, Holzgreve W, Pietrzik K. 2013)
  #2 âVITAMINâ TO AVOID:
 B12 in the form of CYANOCOBALAMIN
 B12 often needs to be supplemented, but cyanocobalamin is not an active form.  âCyanoâ is cyanide, a toxic molecule that must be removed from the cobalamin portion before the body can use it. The body does remove it, but why ingest something that has a cyanide molecule - and is inactive - when other active forms are available?
Good dietary sources of folate are available in vegetables like broccoli, leafy greens, and other plant foods. If you donât eat enough greens or are thinking of getting pregnant, consider a supplement of active folate.
Avoid foods fortified with folic acid!
Folic acid is always listed on an ingredient label. Avoid folic acid fortified foods whenever possible. Unfortunately, commercial flours and breads made with flour all contain folic acid. Choose naturally occurring folate instead.
 B12 is available from animal protein.
Foods like eggs, cheese, meat, shellfish, fish, and poultry are all good sources of B12. Antacids will interfere with the ability to absorb B12, so if you frequently take an antacid or proton-pump inhibitor, beware of B12 deficiency!
Vitamin Resources for Folate and B12:
Here is a vitamin supplement that contains both active folate and active B12 and is free from artificial additives. Another great option for those concerned with common genetic polymorphisms is PureGenomics.
Active naturally occurring folates are commonly referred to as methylfolate and folinic acid on supplement labels. Active folate may also appear as L-5-methylTHF or (6S)-5-methylTHF.
 Active forms of B12, are known as methylcobalamin or adenosylcobalamin.
Folate and B12 actually work together. It is important to make sure B12 is adequate before adding supplemental folate.
Prenatal vitamins are not well defined, and ingredients can vary widely. There are great options that include the active forms of folate and B12: Designs for Health Prenatal Pro.
For those interested in adding physician selected plant-based support, like red raspberry leaf, milk thistle (great for the liver), and ginger, in addition to CoQ10 to support cardiovascular health as well as vitamins and minerals, Seeking Health Optimal Prenatal is a great choice and takes prenatal supplementation to the ânext levelâ.
 If you prefer to choose another brand, here are some additional recommendations specific to prenatal vitamins and supplementation:
Vitamin A (retinol or retinyl palmitate) helps with lung development â many brands only use beta-carotene, which can be converted to vitamin A, but isnât always - and its role is different from vitamin A!
Iodine (to combat chlorine, bromide, and fluoride in the environment and help brain development in the fetus)
Chromium and Molybdenum should be considered
 In conclusion, not all vitamins are created equal and being attentive to the types of ingredients in your supplements is important. If you choose to supplement, make sure your supplement contains the best quality ingredients with the ability to optimally deliver the nutrients it contains.
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 https://www.drbenlynch.com/folic-acid-side-effects/