Reduced UGT activity can be due to various factors, including genetic polymorphisms, liver diseases, drug interactions, and diet. Genetic variations, such as those found in the UGT1A1 gene, can lead to conditions like Gilbert's syndrome, characterized by mild jaundice due to impaired bilirubin metabolism. Liver diseases, such as cirrhosis or hepatitis, can also diminish UGT activity, since UGT enzymes are primarily located in the liver.
