Introduction
As part of my article about optimizing egg quality, it was suggested to be careful to consider what kind of this vitamin (B9) to take. It's generally suggested to opt for folate instead of folic acid as it is more effective. In this article, we'll take a closer look at this system.
Functions
Vitamin B9 (folate) is important in the body as it helps with essential life functions, including:
blood formation, reduces risk for heart/blood vessel diseases, regulates the immune system, assists in normal cell division, normal maternal tissue growth in pregnancy, normal amino acid synthesis, normal psychological functions, reduction of fatigue.
Particularly for pregnancy, it's essential in neural tube development of the fetus. Deficiencies can lead to conditions like spina bifida.
Sources
We usually get folate through consumption of folate rich foods such as liver, dark leafy greens, beans, and yeast. It has been recognized as an essential nutrient and as such it is mandatory to fortify white flour with folic acid (since 1998 in Canada).
It is a water soluble vitamin, and hence not likely to create toxicity. Regularly we need about 200mcg a day, however requirements increase to 400mcg during pregnancy based on NIH recommendations. By the same recommendations, you can reduce back to 200mcg after the 12th week.
Processing
In the body though, folate has to go through a sequence of events converting it to 5-MTHF, which is the active form of the vitamin. Simply put, Folate -> -> -> -> 5-MTHF. Folic acid, the synthetic form, takes an extra step; Folic Acid -> Folate -> -> -> -> 5-MTHF. Therefore folic acid is less desirable as a supplement and folate is usually recommended. (This is only one interpretation - there are some who suggest folic acid is better absorbed in the small intestine)
Looking at the process above, the final step in forming 5-MTHF is taken care by an enzyme known as MTHFR. The catch here is that roughly 20-50% of the population has a inheritable mutation in the gene that creates the MTHFR enzyme. There are different types of mutations which causes different levels of MTHFR deficiency. It can range from 30-70% and thus, even though there are a lot of people with the mutation, not everyone shows the effects.
Taken the MTHFR mutation into account, the preferable supplement is 5-MTHF. It is the active form of the vitamin and also would not be susceptible to MTFHR mutations.
Immunological Infertility
While the most notable role of folate is in the neural tube development, it is important for fertility as a whole. For those dealing with immunological fertility, folate may be of great importance. Immunological fertility can manifest in premature ovarian insufficiency, recurrent IVF implantation failure, recurrent pregnancy loss, testicular failure, longstanding unexplained fertility, PCOS and endometriosis.
In cases of POI, immunological mechanisms may be involved in about 30% of cases. Further, 18-30% also have an autoimmune disease and up to 50% have other evidence of autoimmunity.
(Source: https://bmcimmunol.biomedcentral.com/articles/10.1186/1471-2172-15-11)
The role of folate in this mechanism is to help regulate the immune system function. There are downregulator (calming) functions of certain immune system cells, and these cells have many folate receptors. Without folate, these cells would perish and not be able to calm the immune function.
Estrogen and other toxins
5-MTHF plays an important role in the detoxification of environmental toxins. In our liver, MTHFR is used to convert heavy metals into water soluble compounds so that they can be excreted.
Further, estrogens are detoxified by the action of 5-MTHF. Insufficient 5-MTHF can lead to elevated levels of estrogen in the body, which increases risk uterine fibroids, endometriosis and of breast and prostate cancers.
Conclusion
As with most biological systems, there can be a lot of confusion with respect to what is actually happening inside our bodies. It's easy to say though, that folic acid/folate/5-MTHF are important not only for a healthy pregnancy, but also for fertility and general health. Based on the best available information, if you can afford to, 5-MTHF is the best source of this vitamin. Alternatively, folate is a good second choice as well.