15 mg Active Form Vitamin B9 + B12 Brain, Mood, Heart & Nerve Support USDA Organic Professional Strength Dietary Supplement Discovered in Nature. Optimized by Science. Soy Free Gluten Free GMO Free Vegan GMP Manufactured Certified Organic by Oregon Tilth Most Bioavailable Tissue-Ready Form Methylfolate, or the 5-MTHF form, of vitamin B9 is tissue- ready and the most bioavailable source. It has immediate uptake within the body and does not require any processing to assimilate with blood and cells. When the body consumes other forms of vitamin B9, such as Folate, the body must first convert the Folate to 5-MTHF because that is the form the blood and cells require.