Etiology of Gallstones

Ever since the early investigations of Naunyn1and his associates,2the problem of an excretion of cholesterol and calcium by the gallbladder has remained unsettled in spite of considerable literature on the subject. Since many of these studies were made, the ideas of cholesterol metabolism have undergone such radical changes that a restatement of a few basic facts is important. To begin with, when cholesterol is mentioned, one is apt to think at once of the liver and bile as the important organ in its metabolism. This is totally unwarranted in the light of modern knowledge. In man, the blood contains about twice as much cholesterol as the bile. According to the work of Sperry3and others,4reviewed in a previous paper, the overwhelming proportion of the cholesterol excreted is excreted in the intestinal mucosa, this being a far more important route than the biliary. In