Having recalled the classic works on epidemiology, and having mentioned recent research, the author then considers: 1) Fundamental epidemiological facts. He shows that there is a zone of great varicose occurrence (Western Europe, North America); a zone of mild occurrence (Black Africa, the Far East, the Third World in general); and zones showing discrepancies, (South America, the Mediterranean Basin, India). 2) Explanatory hypotheses concerning the upright posture of Man; prolonged standing; heredity, both clinical (work done by Merlen) and biological (work by Nièbes), affecting the biochemical structure of the venous wall producing degradation of the conjunctive tissue; our way of dressing; the seated position. The terms of a plausible hypothesis must include all the elements defined by Burkitt. 3) Research axes: the role of abdominal hyper-pressure proved by Doppler examination (Folse), provoked by constipation (Cleave) and the idea of an alimentary factor.
