Folate vs Folic Acid - baby's teeth can tell the difference. Osteocalcin inhibition by folic acid may be involved.

High dose folic acid may be inflammatory rather than helping health. A comment about a post by Dr. Jen Gunter turned into a post about osteocalcin and its regulation by folate/folic acid.

Developing babies do seem to be able to tell the difference between synthetic folic acid and natural or synthesized folate.

Development of teeth is delayed 1-2 months in the infants of women who took folic acid - and interestingly, the effect was across the board, gene variants in MTHFR weren’t more at risk for the delay in tooth development. Blood levels of folate and B12 were measured and found to not be correlated with the delay in dental development for the child. (Dhamo, et al., 2021) That is interesting and leads to the question of what is the folic acid doing?

Enough of it must have converted to folate for the women to have normal folate levels, and no impact on the infant from her folate. Excess folic acid can also be used by the body to make purines which are part of DNA and RNA. Might an excess of purines throw off something else? or convert to uric acid and cause an over acidity issue which would negatively affect tooth mineralization? . . . the biochemistry is complex. Giving folic acid can help reduce uric acid levels per some search results, while giving folic acid with a gene difference that causes Lesch-Nyhan disease can cause worse problems. (López, et al., 2020)

We learn in the paper The Regulatory Role of Matrix Proteins in Mineralization of Bone:

• Osteocalcin is involved in late stages of mineralization of bone with hydroxyapatite more than bone matrix formation and it has a role in “dental pulp and newly forming dentin [109].”

• Increased levels of osteocalcin indicates bone formation in glucocorticoid-induced osteoporosis: “Although serum OC concentration is considered a valid marker of bone turnover in most situations, it reflects specifically bone formation when resorption and formation are uncoupled as observed in glucocorticoid-induced osteoporosis.” That suggests stress or cortisol induced osteoporosis would also need osteocalcin for bone formation.

• Vitamin K adequacy is needed for osteocalcin to bind with hydroxyapatite crystals properly: “The hydroxyapatite-binding function of OC necessary for bone mineralization requires the posttranslational carboxylation of the three glutamic acid residues to γ-carboxyglutamic acid by a vitamin K–dependent carboxylase [64]. Inadequate dietary vitamin K intake results in increased concentrations of undercarboxylated osteocalcin (Glu-OC) in children.”

• (Viewable at ScienceDirect/Osteocalcin - an overview)

A study on postmenopausal women with early osteoporosis found that folic acid helped reduce homocysteine levels slightly, but results were mixed on whether it helped bone building biomarkers. It was a small group study. Elevated homocysteine can negatively impact bone mineralization. Osteocalcin levels rose in the control group rather than the folic acid supplemented group. Osteocalcin is a signaling chemical involved in bone building and/or bone resorption - breakdown for reuse of the nutrients. All of the women had somewhat abnormal values at baseline. (Salari, et al., 2014) *See the end of this post for a discussion of osteocalcin - we get more of it when we exercise, and it may help protect against dementia, heart disease, cancer and Type 2 diabetes.

MTHFR gene allele may need riboflavin more than methyl folate

There is not much research that directly compares folate to folic acid for prenatal use. The MTHFR gene variant has been over-hyped and taking extra riboflavin may be the better fix than excessive bioactive folate - too much of that can inhibit the methylation cycles and that is exactly what we don’t want. Supplements of 400-600 mg methyl folate is plenty.

» » » RIBOFLAVIN - The most common variant in the MTHFR gene makes the cofactor B2-riboflavin disconnect, so having plenty of it available helps the MTHFR enzyme reactive for use. The riboflavin is safer than methyl folate as excess of methyl folate can inhibit the methylation cycles. If the body is supposed to make it, then we are not supposed to mega dose supplements of it - generally. NAC or cysteine supplements should also be used with caution as excess will inhibit the methylation cycles. If there is a limiting step anywhere in the interconnected chemical pathways, then the entire clockwork can get jammed up.

Folic acid and folate are terms that may be used interchangeably in science literature, but they are not the same chemically or biologically.

The commonly used form of folic acid is so commonly used that the word is used interchangeably in research studies or textbooks with folate as if they are the same thing. Folic acid is not really a form the body would ever have though, until humans invented it and put it in the food supply and vitamin supplements.

“Although the terms folic acid and folate are used interchangeably, the metabolic effects can be slightly different. Folic acid, which is found in supplements and fortified food, is the synthetic form of folate. Folate is found naturally, mainly in plants.¹ Folate is found in plants and vegetables such as dark leafy greens, broccoli, asparagus, citrus fruits (oranges, grapefruits, strawberries), beans, avocado, peas and lentils, okra, Brussels sprouts, nuts and seeds, cauliflowers, beets, corn, celery, carrots and squash.¹¹ Folate can also be found in meat product including chicken, turkey, lamb, beef and pork liver. Folic acid, on the other hand, can be found in fortified foods, such as cereal, pasta, flour, grains and bread. Folic acid supplements are sold over the counter in tablet or powder forms.¹¹ The daily recommended allowance (RDA) of folic acid in the United States is 400 mcg/day for teenagers and adults, 500 mcg/day for breast-feeding women and 600 mcg/day in pregnancy.^1” (Liew, 2016)

Photo by Alvin Mahmudov on Unsplash

I do not agree with a popular gynecologist’s nutrition guidance for pregnancy. Delivering babies does not make someone an expert on how to grow a healthy baby. It also doesn’t make someone an expert on the value of screening for metabolic gene differences. I think, if health were the real goal of the medical industry, we would screen everyone starting at birth for metabolic gene alleles that are correctable with supplementation. If we can help someone have normal function, then why not do that? Especially if it might help with fetal development too.

A main point in the article by Dr. Gunter is that if ‘synthetic folic acid’ is so bad, then take note that methyl folate in a supplement is probably synthesized too and as it breaks down it would no longer function. True, but it is synthesized in a form that our body is familiar with using and which is found in nature. Folic acid is abnormal to nature and unfamiliar to our bodies. If product breakdown is a significant concern, then the typical 1000 mg folate supplements may be providing at least the desired 400-600 mg. Food sources of truly natural folate include green peas, asparagus, the pulp of citrus fruit, and other green leafy vegetables.

Other findings discussed in a review article about the advisability of taking folic acid supplements show a pattern of elevated levels of folate in cancer and folic acid supplements worsening cancer/risk. Elevated folate levels suggest there already is a dysfunction in the methylation cycle’s normal recycling of folate - instead it accumulated in those patients, and an excess of folate will inhibit the methylation cycles. Lack of normal methylation cycle function is a cancer risk, due to loss of epigenetic methylation within the cell nuclei. Epigenetic control keeps genes turned off when they aren’t needed and allows them to be turned on for protein production when they are needed. Good news — an increased intake of truly natural folate in the form of green leafy vegetables has been shown to protect against cancer. (Liew, 2016)

If fetal tooth development is delayed in the presence of folic acid for any woman, and that issue is not affected by her MTHFR status, (Dhamo, et al., 2021), then it seems all pregnant women would want to know that folic acid is not being used well by her developing infant. I am not finding much research comparing folic acid and folate directly.

Dr. Gunter is recommending that no pregnant person bother to get their MTHFR gene status checked and that no pregnant person should take folate instead of folic acid. Her focus on the ‘evidence’ to support her sweeping recommendations is exclusively regarding studies on Down’s Syndrome. (vajenda.substack) Her comments are only for Paid Subscribers, so she is preventing or isolating her community from receiving opposing information.

It may be worth noting that in this current age of ‘culling by healthcare’ that healthcare professionals who have public presence are likely being promoted/given reach on social media, because their information is supporting the mainstream goals - even if they might seem outspoken or controversial in some way.

Osteocalcin function -

The function of osteocalcin has hormonal signaling roles in the pancreas, testis, and muscle in addition to its primary role in regulation of bone formation or resorption.

Bone Function:

Osteocalcin is a major protein within the bone matrix but is non-collagenous. It is produced by osteoblasts which are the bone cells involved in forming the bone matrix. Osteocalcin when carboxylated will bind with the crystalline hydroxyapatite which is found in bone matrix and within the hardened enamel of our teeth’s surface. Tooth enamel is the hardest material in our body because it has a higher concentration of hydroxyapatite than is found within the bone matrix. The primary function of osteocalcin is to regulate bone metabolism and it is elevated in any condition that has increased bone turnover. It helps regulate the resorption of bone and was elevated in post-menopausal women who had osteoporosis.

Osteocalcin is elevated when there is more bone turnover for varied reasons:

“Osteocalcin levels are increased in metabolic bone diseases with increased bone or osteoid formation, including osteoporosis, osteomalacia, rickets, hyperparathyroidism, renal osteodystrophy, thyrotoxicosis, and in individuals with fractures, acromegaly, and bone metastasis.” (Serum osteocalcin lab test)

Average serum level of osteocalcin for 88 healthy adults was 4.11 +/- 1.43 ng/ml. The level increased with increasing age of the adult:

“Osteocalcin is synthesized by osteoblasts and its concentration in serum is increased when bone metabolism is raised. Radioimmunoassay of serum from 88 healthy adults gave a mean osteocalcin value for the whole group of 4.11 +/- 1.43 ng/ml. The level rose with age.” (Stracke, et al., 1985)

Hormonal function for weight and blood sugar control:

Un-carboxylated osteocalcin has critical functions as signaling hormone in the pancreas and it helps us to make insulin and have better blood sugar regulation and likely helps with weight maintenance. It may help prevent type 2 diabetes.

“Conclusion: Our study showed that serum osteocalcin has some significance as an indicator of metabolic risk, including abdominal obesity and insulin resistance. Bone as well as adipose tissue may be an active organ that regulates energy metabolism.” (Lee, et al., 2012)

Osteocalcin levels are much higher in children aged 6 to 12.9 but was lower in overweight/obese children compared to children of average BMI. A causal relationship or mechanism could not be determined.

“There were significant differences in serum osteocalcin levels between the overweight and control groups (64.00±20.44 vs. 89.56±28.63, P<0.001). Serum osteocalcin levels were inversely correlated with body mass index (BMI) (r=-0.283, P=0.003), weight standard deviation score (SDS) (r=-0.222, P=0.020), BMI SDS (r=-0.297, P=0.002), insulin (r=-0.313, P=0.001), and homeostasis model assessment of insulin resistance (HOMA-IR) index (r=-0.268, P=0.005). In the subsequent multiple regression analyses, BMI, HOMA-IR, and age were determined to be independent predicting factors for serum osteocalcin.” (Oh, et al., 2019)

Hormonal function for male hormone production:

Osteocalcin regulates testosterone synthesis in the testes, and helps regulate the Leydig cells which produce testosterone. This role makes osteocalcin essential for male fertility and development.

Muscle Function:

Osteocalcin helps us to maintain our muscle mass and it helps regulate muscle function, and our response to exercise. Osteocalcin helps with regulation of our synthesis of new muscle protein or breakdown of muscle tissue.

Neuroprotective, cardiovascular and cancer roles of osteocalcin:

Protective roles for osteocalcin have been observed within the brain and cardiovascular system and levels may be disrupted in cancer. Abnormal levels of osteocalcin might be useful as a biomarker for cancer diagnosis or treatment. Normal function of osteocalcin may help protect against neurodegenerative diseases or cardiovascular disease.

Whether the function of osteocalcin within the bone or in other tissues is more important is controversial. Any functional role is an important role.

Brave AI Osteocalcin References

1. pubmed.ncbi.nlm.nih.gov, What is the function of osteocalcin? - PubMed

2. en.wikipedia.org, Osteocalcin - Wikipedia

3. www.frontiersin.org, Frontiers | Osteocalcin—A Ver

4. www.mdpi.com, Functions of Osteocalcin in Bone, Pancreas, Testis, and ...

5. www.sciencedirect.com, What is the function of osteocalcin? - ScienceDirect

6. www.sciencedirect.com, Osteocalcin - an overview | Scie -

Theoretically/hypothetically, folic acid supplementation in pregnancy may be interfering with osteocalcin levels which then leads to delayed tooth mineralization in a developing fetus. . . plausible per Brave AI . . . supplementing folic acid has been observed to increase inflammation in some studies and reduce it in others.

Folic Acid and Osteocalcin Production

Folic acid has been shown to regulate osteocalcin production but the mechanism of action is not known. Folic acid may modulate osteocalcin expression through its effects on gene transcription and epigenetic modifications.

A study published in the journal Advances in Biomedical Research found that folic acid supplementation increased osteocalcin levels in overweight and obese children and adolescents (Dehkordi et al., 2016).

Anti-inflammatory effects of folic acid in a mouse model of osteoporosis: Supplements of folic acid helped reduce negative effects of a high fat diet on osteoporosis in mice. Folic acid supplementation promoted Nrf2 in this group of already obese mice being fed a high fat diet. Methylation cycles would have been shut off by the high fat diet, maybe the folic acid helped replenish folate for the mice. (He, et al., 2022) Deficiency of folate/folic acid has been linked to osteoporosis and supplementation may help due to the effects on osteocalcin production and its role in bone (and tooth) mineralization.

Inflammatory effects seen with high-dose folic acid in pregnancy:

“A study suggested that supplementation of high-dose folic acid during pregnancy might increase the risk of childhood asthma.¹⁰⁶ Crider et al., however, reported in a meta-analysis that there were no evidences of the association between maternal folic acid supplement use (compared with no use) in the pre-pregnancy period through the first trimester and risk of asthma in childhood. However, additional research in this area is needed because of the limited number and types of studies found in the literature.^107” (Liew, 2016)

Brave AI on - “Folic acid and osteocalcin production pubmed”

In conclusion, folic acid plays a crucial role in regulating osteocalcin production, which is essential for bone health. Further research is needed to fully understand the mechanisms by which folic acid affects osteocalcin production and to determine its potential therapeutic applications in bone-related disorders.

1. (Liew, 2016) Liew SC. Folic acid and diseases - supplement it or not? Rev Assoc Med Bras (1992). 2016 Jan-Feb;62(1):90-100. doi: 10.1590/1806-9282.62.01.90. PMID: 27008500. pubmed.ncbi.nlm.nih.gov, Folic acid and diseases - supplement it or not? - PubMed

2. pubmed.ncbi.nlm.nih.gov, Folic Acid Production by Engineered Ashbya gossypii - PubMed production by a modified fungus to reduce the cost of synthesizing folic acid chemically.

3. (He, et al., 2022) He H, Zhang Y, Sun Y, Zhang Y, Xu J, Yang Y, Chen J. Folic Acid Attenuates High-Fat Diet-Induced Osteoporosis Through the AMPK Signaling Pathway. Front Cell Dev Biol. 2022 Jan 3;9:791880. doi: 10.3389/fcell.2021.791880. PMID: 35047504; PMCID: PMC8762056. https://www.frontiersin.org/articles/10.3389/fcell.2021.791880/full

New theory - osteocalcin is inhibited by oxidative stress/NFkb - so inhibiting NFkB might be therapeutic for osteoporosis:

“An imbalance in bone formation relative to bone resorption results in the net bone loss in osteoporosis and inflammatory bone diseases. While it is well known how bone resorption is stimulated, the molecular mechanisms that mediate impaired bone formation are poorly understood. Here we show that the time- and stage-specific inhibition of endogenous IκB kinase (IKK)/nuclear factor-kappa B (NF-κB) NF-κB in differentiated osteoblasts significantly increases trabecular bone mass and bone mineral density without affecting osteoclast activities in young mice. Moreover, the inhibition of IKK/NF-κB in differentiated osteoblasts maintains bone formation, thereby preventing osteoporotic bone loss induced by ovariectomy (OVX) in adult mice. The inhibition of IKK/NF-κB enhances the expression of Fra-1, an essential factor for bone matrix formation in vitro and in vivo. Taken together, our results suggest that targeting IKK/NF-κB may help to promote bone formation in the treatment of osteoporosis and other bone diseases.” (Chang, et al., 2009)

All roads on the chronic inflammation highway lead back to pomegranate extract and other “Natural Products (NPs)” which inhibit NFkB by inhibiting kinases like IκB kinase (IKK) or MAPK and JNK. (Pomegranate/ScienceDirect)

“A pomegranate extract inhibited migration and invasion of oral cancer cells by downregulating matrix metalloproteinases (MMP-2 and MMP-9), as well as epithelial-mesenchymal transition (EMT) signaling [231]. Punicalagin, an isolated pomegranate polyphenol, decreased cell viability, migration, and invasion in breast cancer cells by inhibiting the expression of EMT-related proteins, including MMP-2 and MMP-9 [232]. Both the juice and an aqueous extract of peels inhibited the mTOR/S6K signaling pathway to modulate proliferation, migration, and colony formation in prostate cancer cell lines [233]. Pomegranate modulates several other signaling pathways including NF-κB [234–236], HOXD10 [237], and ROS-JNK-BCL2 [238] to induce cytotoxicity in several cancer cell lines.”

- Natural products action on pathogenic cues in autoimmunity: Efficacy in systemic lupus erythematosus and rheumatoid arthritis as compared to classical treatments, (Pomegranate/ScienceDirect)

Pomegranate extract may be inhibiting kinases by activating bitter taste receptors with are a G-protein coupled receptor. “G-protein coupled receptors: JNKs can be activated by G-protein coupled receptors, which are involved in signal transduction pathways.” - From a Brave AI response.

Does osteocalcin have anything to do with folic acid versus folate? I am not sure. Folic acid given prenatally reduced dental development in the fetus/ ten-year-old child. (Dhamo, et al., 2021) Folic acid given to postmenopausal women with early osteoporosis led to a slightly higher osteocalcin level in the control group - the women who weren’t given folic acid. (Salari, et al., 2014) Osteocalcin is elevated in conditions with bone turnover (Serum osteocalcin lab test) and is decreased in obesity. (Oh, et al., 2019) Inhibiting protein kinases and NFkB may help improve bone formation, (Chang, et al., 2009), and pomegranate extract, curcumin and resveratrol can help with that, (Pomegranate/ScienceDirect), all are Nrf2 promoters and NFkB inhibitors.

Does this suggest that taking folic acid is increasing inflammation in the body somehow? The literature review by (Liew, 2016) suggests that use of folic acid may be less desirable than generally realized. Studies on folic acid and inflammation found that it can inhibit NFkB in some cell types. (Brave AI response)

When asked more bluntly, Brave AI shares that there are mixed results on folic acid supplementation and NFkB - edited, it had errors in the citations and details - info from one reference was copied to another, altering the meaning:

Folic acid supplementation increased NFkB pubmed

Folic acid supplementation has been found to have an impact on the expression of NFκB, a transcription factor involved in various cellular processes, including inflammation and immune response. Studies with different dosages have found an increase or decrease.

One study published in the Journal of Nutrition found that daily supplementation with 5 mg of folic acid for 90 days resulted in increased serum unmetabolized folic acid and reduced natural killer cell cytotoxicity, as well as changes in cytokine mRNA expression, including increased IL8 and TNFA mRNA expressions, which are associated with NFκB activation. (Paniz, et al., 2017)

*To be fair, 5 mg, milligrams, of folic acid would be a mega-huge dose compared to the 0.4 mg = 400 mcg, micrograms, that is recommended for humans. Apparently, that is the standard dose that everyone gets in Brazil. The study authors think such a large dose may have negative consequences. (Paniz, et al., 2017)

“The mechanism by which high concentrations of FA may impair the activity of NK cells remains unclear, and this may only occur in vivo, because in vitro NK cell activity was not modified by concentrations of FA and 5-methyl-THF in cell culture medium (14). We hypothesize that folate receptor 4 (FR4), present in regulatory T (Treg) cells, may be involved in this mechanism. FR4, a subtype of folate receptor, is highly expressed on the surface of Treg cells as a specific marker, distinguishing them from other native or activated T cells (46–48). In turn, Treg cells were shown to be able to profoundly inhibit NK cell functions in animal models, suggesting that Treg cells may play a major role in NK cell regulation (49, 50). However, more studies are needed to confirm this regulation and to deepen our understanding on how this mechanism works.” (Paniz, et al., 2017)

• Another study published in the Polish Heart Journal found that low dose folic acid supplementation of “0.4 mg/24 h for three months” reduced C-reactive protein (CRP) concentrations in both groups, a marker of inflammation, suggesting anti-inflammatory effects. One group had lower dietary intake of folate and that group had improved kidney function. Neither group had significant improvement in inflammatory heart disease markers. (Mierzecki, et al., 2015)

• A study found that folic acid supplementation increased the expression of NF-κB p65/Rela and IL-6 in hypertensive rats, indicating pro-inflammatory effects. (Liu, et al., 2010)

Brave AI - Folic acid supplementation has been shown to have both pro-inflammatory and anti-inflammatory effects on NFκB, depending on the context and dosage.

Brazil mega-doses their population — 5 milligrams of folic acid is the standard and only supplement dose typically available.

“Furthermore, in most countries without mandatory fortification, the general population is not consuming the recommended 0.4 mg of food folate per day. Voluntary fortification improves the situation, but does not reach all parts of the population. In the USA, Canada, and Chile, mandatory fortification of flour substantially improved folate and homocysteine status, and neural tube defects rates fell by between 31% and 78%.” (Eichholzer, et al., 2006)

If mega dose folic acid is affecting Treg cells than my next AI search is for the autoimmune rate in Brazil compared to the US - data is limited to one study in a Brazilian region on 24 autoimmune conditions. The rates were found to be higher than in the US per the AI response but this link suggests the US has ~ 1200/100,000 cases of Hashimoto’s, mostly in women. (pathology.jhu.edu/autoimmune/prevalence)

I found “After age six, Hashimoto is the most common cause of hypothyroidism in the United States and in those areas of the world where iodine intake is adequate. The incidence is estimated to be 0.8 per 1000 per year in men and 3.5 per 1000 per year in women.” Math…. 1200/100,000 = 12 per 1000. The graphic seems wrong, but a rate of 350 + 80 = 430/100,000 is worse than “140.6 cases per 100,000 (95% CI: 112.4–173.9)”. (Tolentino, Jr., et al., 2019) Autoimmune disease is not looking good in Brazil, but it looks worse in the US, so mega-doses of folic acid may not be as big of a risk as living in the US is ;-)

This graphic seems wrong regarding Hashimoto’s rate. (pathology.jhu.edu/autoimmune/prevalence)

“The prevalence of autoimmune diseases in this region was 673.6 cases per 100,000 inhabitants [95% confidence interval (CI): 609.8–742.4]. Highest prevalence was identified for Hashimoto’s thyroiditis 140.6 cases per 100,000 (95% CI: 112.4–173.9), followed by vitiligo 132.4 cases per 100,000 (95% CI: 105.0–164.8), and rheumatoid arthritis 105.9 cases per 100,000 (95% CI: 81.6–135.3). The sex ratio was higher in females (69%), the most affected age group was over 60 years (30.5%), with greater predominance in the urban area (81.3%).” (Tolentino, Jr., et al., 2019)

Urban based females would be most likely to cooperate with recommendations for taking a folic acid supplement…and reducing risk of Down’s Syndrome.

Disclaimer: This information is being provided for educational purposes within the guidelines of Fair Use and is not intended to provide individual health care guidance.

Reference List

(Chang, et al., 2009) Chang J, Wang Z, Tang E, Fan Z, McCauley L, Franceschi R, Guan K, Krebsbach PH, Wang CY. Inhibition of osteoblastic bone formation by nuclear factor-kappaB. Nat Med. 2009 Jun;15(6):682-9. doi: 10.1038/nm.1954. PMID: 19448637; PMCID: PMC2768554. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC2768554/

(Dhamo, et al., 2021) Dhamo B, Jaddoe VWV, Steegers EAP, Wolvius EB, Ongkosuwito EM. The association of maternal folic acid supplementation and prenatal folate and vitamin B12 concentrations with child dental development. Community Dent Oral Epidemiol. 2021 Oct;49(5):445-453. doi: 10.1111/cdoe.12620. Epub 2021 Jan 24. PMID: 33486813; PMCID: PMC8518742. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC8518742/

(Eichholzer, et al., 2006) Eichholzer M, Tönz O, Zimmermann R. Folic acid: a public-health challenge. Lancet. 2006;367:1352–61. https://pubmed.ncbi.nlm.nih.gov/16631914/

(Lee, et al., 2012) Lee SW, Jo HH, Kim MR, You YO, Kim JH. Association between obesity, metabolic risks and serum osteocalcin level in postmenopausal women. Gynecol Endocrinol. 2012 Jun;28(6):472-7. doi: 10.3109/09513590.2011.633660. Epub 2011 Nov 24. PMID: 22114890. https://pubmed.ncbi.nlm.nih.gov/22114890/

(López, et al., 2020) López JM, Outtrim EL, Fu R, Sutcliffe DJ, Torres RJ, Jinnah HA. Physiological levels of folic acid reveal purine alterations in Lesch-Nyhan disease. Proc Natl Acad Sci U S A. 2020 Jun 2;117(22):12071-12079. doi: 10.1073/pnas.2003475117. Epub 2020 May 19. PMID: 32430324; PMCID: PMC7275668. https://www.pnas.org/doi/10.1073/pnas.2003475117

(Liu, et al., 2010) Liu H, Huang GW, Zhang XM, Ren DL, X Wilson J. Folic Acid supplementation stimulates notch signaling and cell proliferation in embryonic neural stem cells. J Clin Biochem Nutr. 2010 Sep;47(2):174-80. doi: 10.3164/jcbn.10-47. Epub 2010 Aug 20. PMID: 20838574; PMCID: PMC2935158. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC2935158/

(Mierzecki, et al., 2015) Mierzecki A, Makarewicz-Wujec M, Kłoda K, Kozłowska-Wojciechowska M, Pieńkowski P, Naruszewicz M. Influence of folic acid supplementation on coagulation, inflammatory, lipid, and kidney function parameters in subjects with low and moderate content of folic acid in the diet. Kardiol Pol. 2015;73(4):280-6. doi: 10.5603/KP.a2014.0209. Epub 2014 Nov 5. PMID: 25371306. https://journals.viamedica.pl/polish_heart_journal/article/view/KP.a2014.0209/57352

(Oh, et al., 2019) Oh SB, Lee WY, Nam HK, Rhie YJ, Lee KH. Serum osteocalcin levels in overweight children. Ann Pediatr Endocrinol Metab. 2019 Jun;24(2):104-107. doi: 10.6065/apem.2019.24.2.104. Epub 2019 Jun 30. PMID: 31261474; PMCID: PMC6603608. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC6603608/

(Paniz, et al., 2017) Paniz C, Bertinato JF, Lucena MR, De Carli E, Amorim PMDS, Gomes GW, Palchetti CZ, Figueiredo MS, Pfeiffer CM, Fazili Z, Green R, Guerra-Shinohara EM. A Daily Dose of 5 mg Folic Acid for 90 Days Is Associated with Increased Serum Unmetabolized Folic Acid and Reduced Natural Killer Cell Cytotoxicity in Healthy Brazilian Adults. J Nutr. 2017 Sep;147(9):1677-1685. doi: 10.3945/jn.117.247445. Epub 2017 Jul 19. PMID: 28724658; PMCID: PMC5712455. https://www.sciencedirect.com/science/article/pii/S0022316622108394

(Pomegranate/ScienceDirect) https://www.sciencedirect.com/topics/pharmacology-toxicology-and-pharmaceutical-science/pomegranate-extract See the first article: Natural products action on pathogenic cues in autoimmunity: Efficacy in systemic lupus erythematosus and rheumatoid arthritis as compared to classical treatments

(Salari, et al., 2014) Salari P, Abdollahi M, Heshmat R, Meybodi HA, Razi F. Effect of folic acid on bone metabolism: a randomized double blind clinical trial in postmenopausal osteoporotic women. Daru. 2014 Sep 16;22(1):62. doi: 10.1186/s40199-014-0062-9. PMID: 25223378; PMCID: PMC4172791. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4172791/

(Stracke, et al., 1985) Stracke H, Schatz C, Pralle H, Ullmann J, Schatz H. Osteocalcin, ein Marker bei Erkrankungen mit erhöhtem Knochenumsatz [Osteocalcin, a marker in diseases with elevated bone metabolism]. Dtsch Med Wochenschr. 1985 Sep 20;110(38):1442-6. German. doi: 10.1055/s-2008-1069025. PMID: 3875469. https://www.thieme-connect.com/products/ejournals/abstract/10.1055/s-2008-1069025

(Tolentino, Jr., et al., 2019) Tolentino Júnior DS, de Oliveira CM, de Assis EM. Population-based Study of 24 Autoimmune Diseases Carried Out in a Brazilian Microregion. J Epidemiol Glob Health. 2019 Dec;9(4):243-251. doi: 10.2991/jegh.k.190920.001. PMID: 31854165; PMCID: PMC7310795. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC7310795/