5-MTHF is 20% for the month of May. This is the only supplement that I have some patients on permanently. A huge segment of our population (15-25%) have a genetic defect that prevents them from adequately converting folic acid to its final usable form. Folate is needed for proper development, reducing inflammation and pain, several detoxification pathways, for reducing allergic reaction, reducing depression and anxiety. This is a huge deal and it is the only supplement that I will put on sale twice a year.