Prenatal folate and folic acid levels; NTDs, a multifactorial problem.

I added a link to the last post that needs more attention. Multifactorial problems require complex solutions with a checklist to help screen for the potential causal factors.

A study on folate and folic acid supplementation in pregnancy by Cochrane, et al., tests whether supplements of the bioactive form of folic acid, naturally found in food, 5-THF folate, is effecting folic acid levels prenatally. Testing the obvious, they found that indeed it does reduce inactive folic acid blood levels when women take 5-THF. (Cochrane, et al., 2023)

The team did not measure prenatal health outcomes and the Abstract is written with the tone that this is mysterious and that 5-THF might be a bad thing because folic acid is recommended for prenatal use …. and implication, that therefore it is needed for pregnancy - so, implication, reducing folic acid levels would be a negative effect of taking supplements that have 5-THF instead. The body of the paper and discussion make it clear that Cochrane et al., do have a wider view than my negative read of the Abstract and do question whether women may be getting too much of the inactive folic acid in diet and supplements for optimal health. They recommend more study of the stability of active folate forms in supplements and of the question of value prenatally for reducing NTD risk. Other studies on the question have shown benefit or risk, or no effect. (Cochrane, et al., 2023)

Based on my review of nutrients involved in NTD risk - a well written study would need to evaluate all of the prenatal participants not only for folic acid, but also for their level of methyl folate and methyl/hydroxy B12 (is the active form present or only cyanocobalamin?), choline, vitamins B2, and B6, zinc, betaine (TMG), Dimethylglycine, and whether there is elevated homocysteine. Purine Nucleotides availability and Iron and iodine might also have impact if deficient. (Substack) An addition - cholesterol blocking drugs are likely a risk of NTDS if a premenopausal woman becomes pregnant while taking statin drugs or a newer medication affecting cholesterol metabolism (PCSK9 inhibitor). (Husten, 2016)

Multifactorial problems are complex to study because of the multiple potential causal variables. Promising someone a reduced Neural Tube Defect risk in their infant if they take a 400 or 600 mcg supplement of folic acid or active methyl folate will not guarantee that desirable outcome if the person is also low in other B vitamins and zinc or have reduced cholesterol sulfate availability.

Lack or excess of active forms of vitamin A or D could also interfere with fetal cholesterol metabolism in a way that may cause NTDs. More on that topic is at the end of this post.

Providing too little information to patients regarding health risks gives a false sense of security - “I am taking my folic acid supplement so my baby WILL be safe from Neural Tube Defect risks!” That would be false comfort and not helpful enough if a woman is missing other B vitamins, zinc, is taking cholesterol blocking medications, or is following a vegan or vegetarian diet that is low in cholesterol and choline (eat egg yolks when pregnant!).

The Abstract, (Cochrane, et al., 2023) :

Folic acid supplementation is recommended during pregnancy to support healthy fetal development;

(6S)-5-methyltetrahydrofolic acid [(6S)-5-MTHF] is available in some commercial prenatal vitamins an alternative to folic acid,

but its effect on blood folate status during pregnancy is unknown.

To address this, we randomized 60 pregnant individuals at 8-21 weeks’ gestation to 0.6 mg/day folic acid or (6S)-5-MTHF x 16-weeks. Fasting blood specimens were collected at baseline and after 16-weeks (endline). Red blood cell (RBC) and serum folate were quantified via microbiological assay (as globally recommended) and plasma unmetabolized folic acid (UMFA) via LC-MS/MS. Differences in biochemical folate markers between groups were explored using multivariable linear/quantile regression, adjusting for baseline concentrations, dietary folate intake, and gestational weeks. At endline (n=54), the mean ± SD (or median, IQR) RBC folate, serum folate, and plasma UMFA (nmol/L) in those supplemented with (6S)-5- MTHF versus folic acid, respectively, was: 1826 ± 471 and 1998 ± 421; 70 ± 13 and 78 ± 17; 0.5 (0.4, 0.8) and 1.3 (0.9, 2.1).

In regression analyses, RBC and serum folate did not differ by treatment group;

however, concentrations of plasma UMFA in pregnancy were 0.6 nmol/L higher (95% CI: 0.2-1.1) in those supplementing with folic acid as compared to (6S)-5-MTHF.

In conclusion, supplementation with (6S)-5-MTHF may reduce plasma UMFA by ~50% as compared to supplementation with folic acid, the biological relevance of which is unclear. As folate is currently available for purchase in both forms, the impact of circulating maternal UMFA on perinatal outcomes needs to be determined.” (Cochrane, et al., 2023)

The implications are very negative within the Abstract alone. It includes no information about the neural tube defect reason to assure adequate folate levels, and does not mention that folic acid is synthetic and therefore not even a chemical that should be in a human body if we were running around as nature set up for us. Folic acid might not be safe in larger quantities for pregnancy is what a recent post turned up, along with a long list of other causal factors for Neural Tube Defects occurring in the fetus, above and beyond the question of folate/folic acid adequacy or excess.

The paper does include some of that background information in the Introduction but did not dig as far into the question of NTDs and folate/folic acid as my post did - they miss the purine signaling value of folic acid as a precursor chemical for adenosine (ATP/ADP and a nucleotide in DNA and RNA).

“However, there is no clear messaging from public health agencies regarding the difference of supplemental folate forms for pregnant individuals, as the effect of (6S)-5-MTHF on folate status during pregnancy has never been evaluated, and only folic acid has been shown to reduce the risk of NTDs in randomized controlled trials(19–21) .” […]

“Excess folic acid intake has been associated with various adverse health outcomes for both the mother and child(10,13,17) . Clinical concerns related to offspring health include neurodevelopmental disorders(56–63) , allergic diseases(64–68) , metabolic outcomes(17,69–72) , and poor fetal growth (small-for-gestational-age birth; SGA) (73,74) . However, results in human studies are mixed, with some reporting a harmful association(58,63–65,73) , null findings(56,59,66–68,75) , or a protective effect(57,60–62,74) of maternal folic acid supplementation. Further, the effects of folic acid may vary by dose; for example, folic acid supplementation at recommended doses (0.4 mg/day) is associated with a reduced risk of SGA(74) , whereas intakes >1.0 mg have shown an increased risk(73) . It is proposed that UMFA demonstrates a dose-response relation with adverse outcomes, whereby higher UMFA is associated with greater risk(13,76)” (Cochrane, et al., 2023)

Folic acid may be helpful in lower amounts while being harmful in excess as it may block access to methylated folate in critical reactions.

The Discussion section goes into more detail about concerns - the active folate forms may be less stable as a food fortification or in a supplement and there is increased cost compared to folic acid. On the caution side the authors refer to studies showing that the average woman has fairly high blood levels of inactive folic acid, possibly unsafe levels, due to the widespread fortification of food with folic acid and the fact that prenatal vitamins generally have 600 to 1000mcg instead of the 400 mcg that has been found to be generally safe. The team is saying it would be difficult now to have folic acid intake of only 400 mcg/day and not exceed the “Tolerable Upper Intake Level of 1.0 mg/day folic acid(12,79–81,85).” (Cochrane, et al., 2023)

Folic acid may help protect against NTDS due to conversion into purines.

Folic acid may be helpful as a purine/nucleotide precursor and it wouldn’t need to be methylated to perform in that role. Pregnancy would have an increased need for more RNA and DNA production as all of the proteins that are made need one messenger RNA made for transcription of each protein. Each mRNA may have 100s of nucleotides of which adenine and guanine are two of the four possible. Purines may also be used for energy by a cell - adenosine triphosphate (ATP) releases energy when dephosphorylated into adenosine diphosphate (ADP). (diffen.com)

ATP is like our energy currency, we need plenty for our energy level, and it is also used in signaling and control of cell actions. Purinergic signaling is critical for neurodevelopment of the fetus and after the birth. (Fumagalli, et al., 2017)

However, purines could also be made when there is adequacy of methyl folate - just the way it happened before synthetic folic acid was introduced to the food supply. Two methyl folates in combination, 10-formyltetrahydrofolate (10-formyl-H₄folate), are used by two enzymes for production of purines. Glycine, histidine or formate may be used for the carbon additions to the 10-formyl-H₄folate. (Baggott, Tamura, 2015)

In Figure 2 below, (Baggott, Tamura, 2015), we can see that 4-methyl folate or 5-methylfolate may be used to make purines in a few different ways depending on which enzyme is used and the carbon donating chemical, histidine or formate, or glycine which might be made from serine.

“FIGURE 2. Metabolic pathway of 10-formyl-H₄folate formed from H₄folate and [ring 2-carbon]histidine, [3-carbon]serine, [2-carbon]glycine, and formate. […] Reproduced from Reference 4 with permission.” (Baggott, Tamura, 2015)

See this post/ actually no, this one is short, and then I added the follow-up that got long.

• Folate or Folic acid, pre-conception to week 5-8 prenatally, may reduce NTDS & autism risk. Recent review report by the US Preventive Services Task Force. And, lean muscle mass is protective against Alzheimer's risk. (Substack)

See this Not Brief post (the original title was Brief …review.)

• Not brief review of nutrient deficiencies that might cause Neural Tube Defects, and why folic acid might help a little even with it not being methylated.

  It was brief when I got started. Too long for email. /Included: methyl folate & B12, choline, B2, B6, zinc, betaine, Dimethylglycine. Purine Nucleotides. Iron, iodine, prenatal vitamins & tolerance. (Substack)

Cholesterol metabolism prenatally could be negatively effected by a lack or an excess of activated vitamin D or vitamin A.

“In normal epidermis, cholesterol sulfate is generated by cholesterol sulfotransferase (SULT2B1b), but desulfated in the outer epidermis, together forming a ‘cholesterol sulfate cycle’ that potently regulates epidermal differentiation, barrier function and desquamation.” (Elias, et al., 2014)

This paper looks at a gene difference seen in humans that is different for affected males or females due to a protective effect of having a gene on the female X chromosome - females may have one good copy while a male would only have one copy. It causes skin growth differences leading to a scale-like effect. (Elias, et al., 2014)

“SSase (EC 3.1.6.2, arylsulfatase-C) is a member of a superfamily of 12 different mammalian sulfatases that hydrolyze alkyl steroid sulfates (e.g., dehydroepiandrosterone sulfate [DHEAs]) and aryl steroid sulfates (e.g., estrone sulfate) to their unconjugated forms (Fig. 1). […]

While cytokines such as TNFα and IL-6 upregulate enzyme activity, IL-1β instead reportedly downregulates SSase activity [55], although IL-1β (as well as interferon γ) reportedly down-regulate SSase expression by inhibiting NFkB, while activating the glucocorticoidreceptor [55]. Finally, both retinoids and 1,25(OH)₂ vitamin D3 induce both SSase activity and expression [56].” (Elias, et al., 2014)

Good health is a miracle, not a guarantee - that is my take home point for you. too often the medical approach is to simplify a problem, which helps to examine that aspect of the larger picture but can also fail to see the larger picture.

In this case the larger picture is that ‘folic acid supplementation prenatally to prevent Neural Tube Defects’ is only one small part of a larger picture. Examining that same question over and over and over again will always lead to mixed or inconclusive results because some women may need other B vitamins, zinc, and functioning cholesterol sulfate metabolism, in addition to have adequate but not excessive active vitamin D and vitamin A. Iodine and thyroid hormone adequacy likely play a role too as the three receptors can affect the gene transcription of each other and lack of zinc for zinc finger proteins may also disrupt gene transcription.

A balanced diet and a balanced vitamin/mineral supplement is about getting plenty of all the nutrients without an excess of any of them. The recent publication by (Cochrane, et al., 2023) brings up the very good question of whether prenatally women may be getting too much inactive folic acid from their diet and supplement sources.

To repeat:

“Excess folic acid intake has been associated with various adverse health outcomes for both the mother and child(10,13,17) . Clinical concerns related to offspring health include neurodevelopmental disorders(56–63) , allergic diseases(64–68) , metabolic outcomes(17,69–72) , and poor fetal growth (small-for-gestational-age birth; SGA) (73,74) . However, results in human studies are mixed, with some reporting a harmful association(58,63–65,73) , null findings(56,59,66–68,75) , or a protective effect(57,60–62,74) of maternal folic acid supplementation. Further, the effects of folic acid may vary by dose; for example, folic acid supplementation at recommended doses (0.4 mg/day) is associated with a reduced risk of SGA(74) , whereas intakes >1.0 mg have shown an increased risk(73) . It is proposed that [unmetabolized folic acid] UMFA demonstrates a dose-response relation with adverse outcomes, whereby higher UMFA is associated with greater risk(13,76)” (Cochrane, et al., 2023)

The discussion by Cochrane, et al., concludes with the point that theirs was a small group study and larger trials are advised to check the 95% Confidence Interval of their results which suggest 600 mcg of folic acid affects blood levels of folate more than a folate supplement and they also suggest checking the babies for neurodevelopment and fetal growth (Small for Gestational Age was associated with excess folic acid).

“Both biochemical (e.g., folate status, plasma UMFA) and clinical outcomes should be evaluated in a definitive trial; we suggest assessment of fetal growth and neurodevelopment as outcomes of interest(10,13) .” (Cochrane, et al., 2023)

I would also suggest assessment of methyl/hydroxy B12, B2, B6, choline, betaine, DMG/glycine, zinc, iodine, inactive and active vitamin A and vitamin D, cholesterol, sulfate, and magnesium levels (because magnesium inadequacy interferes with vitamin D and A metabolism). Purine levels may also be helpful and ruling out elevated homocysteine is a need for preventing Neural Tube Defects.

The most severe type of NTDs is anencephaly - the baby is born with a deformed brain and skull and will die - would not be able to function viably for very long. Scoliosis, curvature of the spine or of muscle proprioception, is a more common Neural Tube Defect

Photo by Liv Bruce on Unsplash

Disclaimer: Opinions are my own and the information is provided for educational purposes within the guidelines of Fair Use. While I am a Registered Dietitian this information is not intended to provide individual health guidance. Please see a *functional health professional for individual health care purposes.

Reference List

(Baggott, Tamura, 2015) Baggott, J.E., Tamura, T., Folate-Dependent Purine Nucleotide Biosynthesis in Humans, Advances in Nutrition, 6(5), P564-571, SEPT 2015, DOI:https://doi.org/10.3945/an.115.008300 https://advances.nutrition.org/article/S2161-8313(23)00101-1/fulltext “FIGURE 2. Metabolic pathway of 10-formyl-H₄folate formed from H₄folate and [ring 2-carbon]histidine, [3-carbon]serine, [2-carbon]glycine, and formate. […] Reproduced from reference 4 (Figure 1) with permission.”

(Cochrane, et al., 2023) Cochrane, K.M., Elango, R., Devlin, A.M., Mayer, C., Hutcheon, J.A., Karakochuk, C.D., (2023), Supplementation with (6S)-5-methyltetrahydrofolic acid appears as effective as folic acid in maintaining maternal folate status while reducing unmetabolized folic acid in maternal plasma: A randomized trial of pregnant women in Canada, British J of Nutrition, DOI 10.1017/S0007114523001733, Published online Aug 10, 2023, https://www.cambridge.org/core/journals/british-journal-of-nutrition/article/supplementation-with-6s5methyltetrahydrofolic-acid-appears-as-effective-as-folic-acid-in-maintaining-maternal-folate-status-while-reducing-unmetabolized-folic-acid-in-maternal-plasma-a-randomized-trial-of-pregnant-women-in-canada/A07396C9FBD5A56E4B3D6BCB5D465CBA

(Elias, et al., 2014) Elias PM, Williams ML, Choi EH, Feingold KR. Role of cholesterol sulfate in epidermal structure and function: lessons from X-linked ichthyosis. Biochim Biophys Acta. 2014 Mar;1841(3):353-61. doi: 10.1016/j.bbalip.2013.11.009. Epub 2013 Nov 27. PMID: 24291327; PMCID: PMC3966299. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3966299/

(Fumagalli, et al., 2017) Fumagalli M, Lecca D, Abbracchio MP, Ceruti S. Pathophysiological Role of Purines and Pyrimidines in Neurodevelopment: Unveiling New Pharmacological Approaches to Congenital Brain Diseases. Front Pharmacol. 2017 Dec 19;8:941. doi: 10.3389/fphar.2017.00941. PMID: 29375373; PMCID: PMC5770749. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5770749/

(Husten, 2016) ‘CardioBrief: Neural Tube Defects Linked to Lower PCSK9 Levels’ — Rat study prompts speculation on risk with new cholesterol drugs, Jan , 2016, medpagetoday.com, https://www.medpagetoday.com/cardiology/cardiobrief/55506