Benefits
Shelf-stable crystal form
Quatrefolic®'s glucosamine salt crystal form is shelf-stable and easy to formulate. Head-to-head data showing it is more stable or better absorbed than other L-5-MTHF crystals are limited, so this is a manufacturing quality point, not a separate health benefit.
Raises blood folate when swallowed
Pharmacokinetic studies of oral [6S]-5-MTHF show it raises plasma folate. In a single-dose crossover in healthy men, its short-term bioavailability was equivalent to folic acid, not dramatically higher. The published pharmacokinetic work used generic [6S]-5-MTHF material, not Quatrefolic-branded product.
FDA GRAS status
Quatrefolic® has FDA Generally Recognized as Safe (GRAS) status — important for clinical-grade supplement formulations and prescription medical foods. Other active folate forms, such as Metafolin, also hold GRAS status, so this is a shared regulatory point, not a Quatrefolic advantage.
Pregnancy and prenatal applications
Active folate forms are widely used in prenatal vitamins for women who prefer them or who carry MTHFR variants. A randomised trial in pregnant women found (6S)-5-MTHF kept red-cell and serum folate as high as folic acid did. That trial measured maternal folate status, not neural-tube-defect or birth outcomes, and used generic (6S)-5-MTHF rather than the Quatrefolic brand.
Homocysteine reduction with documented effects
Quatrefolic® clinical trials document homocysteine reduction in adults with elevated baseline levels. In randomised trials, [6S]-5-MTHF lowered homocysteine to the same degree as folic acid, not more. Homocysteine is a blood marker, not a measured heart-disease outcome.
Quality control for clinical applications
Pharmaceutical-grade manufacturing is used in some medical foods and prescription products. This is a manufacturing-quality attribute, not a measured health benefit for the person taking it.
Mechanism of action
Direct active folate provision
Quatrefolic® provides L-5-MTHF directly in active form. Bypasses MTHFR enzyme conversion that's impaired in 40-50% of population with gene variants. Mechanism foundation for the MTHFR-bypass applications.
Stable crystal form for bioavailability
Patented glucosamine salt crystal provides stable methylfolate that survives stomach acid and intestinal processing. Head-to-head data showing that generic L-5-MTHF crystals degrade faster or deliver less folate are limited, so treat this as a formulation-quality point rather than a proven difference.
Methylation cycle support
Once absorbed, Quatrefolic® L-5-MTHF participates in the methylation cycle as a methyl donor for methionine synthesis. Supports DNA methylation, neurotransmitter synthesis, and homocysteine metabolism.
Clinical trials
Quatrefolic® clinical trials document homocysteine reduction in adults with elevated baseline levels.
Clinical population described in trial publication.
Quatrefolic® clinical trials document homocysteine reduction in adults with elevated baseline levels. In these randomised trials [6S]-5-MTHF lowered homocysteine to the same extent as folic acid, not more. The studies used generic [6S]-5-MTHF material, not Quatrefolic-branded product, so they do not validate the brand specifically.
Clinical use in pregnancy formulations supports adequate folate intake during pregnancy and lactation.
Clinical population described in trial publication.
A randomised trial in 60 pregnant women found (6S)-5-MTHF maintained red-cell and serum folate as well as folic acid and lowered unmetabolised folic acid. It measured maternal folate status, a blood marker, not neural-tube-defect or birth outcomes, and used generic (6S)-5-MTHF rather than the Quatrefolic brand.
Pharmacokinetic studies document Quatrefolic® bioavailability and time-to-peak.
Clinical population described in trial publication.
Single-dose pharmacokinetic studies of [6S]-5-MTHF show it raises plasma folate, with short-term bioavailability equivalent to folic acid. These studies used generic [6S]-5-MTHF material, not Quatrefolic-branded product.