Summary Bacterial β‐glucuronidase in the human colon plays an important role in cleaving liver conjugates of dietary compounds and xenobiotics, while other glycosidase activities are involved in the conversion of dietary plant glycosides. Here we detected an increase in β‐glucuronidase activity in faecal samples from obese volunteers following a high‐protein moderate carbohydrate weight‐loss diet, compared with a weight mainte...