Folate, or vitamin B9, is an essential nutrient for human health. Reactions involving folate are important to every body system. Folate supports neurological function, healthy cellular energy metabolism, cellular repair and function, and healthy fetal development. Folate is also critical to the methylation cycle and the support of healthy homocysteine levels that are important for cardiovascular health.

Folate acts as a coenzyme or co-substrate in the metabolism of amino acids and the synthesis of nucleic acids. A critical folate-dependent pathway involves the conversion of homocysteine to methionine in the synthesis of S-adenosyl-methionine in support of its role as a methyl donor. The methylation of deoxyuridylate to thymidylate in the formation of DNA is another critical folate-dependent reaction.

Folate is present in many foods, including vegetables, beans, fruits, nuts, meat, poultry, seafood, and eggs. Folate deficiency usually exists alongside other nutrient deficiencies due to its association with malabsorptive disorders. Folate deficiencies may result in megaloblastic anemia, neural tube defects, and other potential birth defects.

A study authored by Ewies and colleagues explored the possible relationship between folic acid (an oxidized form of folate) and hot flash amelioration of patients from nine hospitals in the United Kingdom. Of note, the American terminology of hot flash is used interchangeably with the British term hot flush, as described in this study. The multicenter, randomized, placebo-controlled clinical trial assessed the efficacy of supplementation with folic acid on postmenopausal women experiencing hot flashes. There were 164 participants in the 12-week study. The treatment arm participants received 5 mg of folic acid daily.

Study results indicated that supplementation with folic acid improved “hot flush scores” in a statistically significant manner. The authors reported that further studies with larger populations are needed before conclusions can be drawn.

Although folic acid supplementation was used in the study by Ewies and colleagues, research indicates that certain other bioidentical forms of folate may be superior to folic acid supplementation. For instance, [6S]5-methyltetrahydrofolate ([6S]5-MTHF) is a bioidentical form of folate that has been shown in animal studies to have improved bioavailability in oral use, high solubility in water, and long-lasting stability when compared with folic acid.

The mucosal cells in the small intestine absorb both [6S]5-MTHF and folic acid. The mucosal cells that convert folic acid into [6S]5-MTHF have limited capacity and may become saturated. Excess folic acid is then absorbed into the bloodstream, and in a vitamin B12-independent pathway, it may be reduced to tetrahydrofolate, which can mask a deficiency in vitamin B12. In addition, variations related to methylenetetrahydrofolate reductase (MTHFR) and other genes may render some individuals with a reduced ability to convert folic acid.

Folate may support cellular health, healthy DNA repair, amino acid synthesis, homocysteine levels, and fetal development. It is essential for many functions within the human body. New research indicates that it may also support a healthy response to hot flashes in postmenopausal women.

By Colleen Ambrose, ND, MAT