The once-prevalent disease known as chlorosis, that for centuries has been considered as typical of young unmarried women, is--in the history of Medicine--one of the few for which the abundant medical literature allow to assign the exact date of beginning in the sixteenth century--and its disappearance in early twentieth century. Origin and history of chlorosis--along four centuries--are an intriguing example of how sickness is not only related to the history of medical science, but it is also deeply rooted to the history of the imaginary, mentalities, culture and social trends. But that's not all. In general, through the history of chlorosis it is possible to focus some important issues: the transformation of puberty and adolescence in medical problems; the growing medicalization of the society that is reflected in the gradual inclusion into the scientific medical discourse of social and cultural issues (the status, the emancipation of women, etc...). Using a range of medical writings and treatises, supplemented with statistical data, this article focuses on the spread of the chlorosis--the incidence of which apparently increased at that time--and explores the interpretations of the disease in Nineteenth Century Italy. A "golden age" of medical debate and speculations about the disease, that even after the developments of haematology and its diagnostic identification as hypochromic anaemia, will continue for a long time to carry the weight of the nervous and emotional factors that had accompanied the chlorosis for centuries.