UGT1A6 encodes an enzyme that prepares molecules such as steroids, hormones (estrogen & thyroxine) and drugs (morphine & acetaminophen), and bilirubin, for excretion via urine and bile. Glucuronidation turns lipophilic compounds into water-soluble compounds which are easily excreted in the urine and bile. Variants on UGT1A6 can cause low enzyme activity. Due to the bacterial production of an enzyme called beta-glucuronidase, intestinal dysbiosis can cause inactivated (conjugated) compounds to become reactivated (unconjugated) and re-released into circulation.
The AG result is associated with reduced UGT1A6 activity and reduced inactivation and elimination of estrogen, thyroxine and other substances detoxified by this pathway. It is also linked to increased risk of gallstones. Intestinal dysbiosis will impede this pathway further. Foods that support this pathway include apples, oranges and cruciferous vegetables (all of which naturally contain calcium-D-glucarate, a compound shown to inhibit beta-glucuronidase released by gut bacteria), and watercress.