What percentage of cholecystectomies cause post cholecystectomy syndrome?

10-40%: Up to 40% have some degree of post-cholecystectomy syndrome though it often improves so only about 10-15% of cases are chronic. There are a variety of causes and sometimes the cause is not found, but dietary changes and supplements can often help. See https://www.hormonesmatter.com/problems-gallbladder-removal-postcholecystectomy-syndrome/