Furthermore, because formate can be converted from methanol through formaldehyde primarily by alcohol dehydrogenases and can also be produced by gut microbiota [63], the increased levels of formate in urine and decreased levels in serum in the WKN group may reflect the intervention effects on gut microbiota and metabolic clearance mechanisms that are involved in WKN's effects in FD. This evidence concerns the gene AKR1A1 and Fabry disease.