Ship dropsy was the term applied to malnutritional edema when it developed, as it frequently did, in sailors and passengers, on the old-time sailing vessels. These people were at sea for long periods and their diet was composed of hardtack, salt meats and other salted foods and water. They lacked all fresh foods. Prison dropsy was the term applied to the same condition when it developed, as it commonly did, in prison inmates on a similar diet. Famine dropsy was the term used to designate malnutritional edema developing in famine victims, whose diet, also, was of a similar kind with plenty of salt.

Sodium chloride has a paralyzing effect upon endothelial activity. Edema can be induced by large quantities of salt. Ship dropsy, famine dropsy, malnutritional edema may be due, as much to the ingestion of large quantities of salt (coincident with a lessened intake of bases) and water as to the actual food deficiencies. Where edema develops in one whose diet contains common salt there will always be retention of this substance in the blood.

Berg says: "As a matter of experience, all observers are agreed that in malnutritional edema there is a retention of sodium chloride by the body, and that when the edema subsides there is a profuse excretion of the salt. Burger noted that when the edema was setting in, there was marked craving for sodium chloride, although as much as 12 grammes were consumed daily. The explanation doubtless is that during the onset of malnutritional edema, as during all the maladies dependent upon an ill-balanced diet, there gradually arises a loss of appetite, and sometimes a positive loathing for food, the patient attempts to stimulate appetite by over-seasoning the food,"

It would be difficult to determine how much of this dropsy is due to dietary deficiency and how much is due to the large use of salt. There can be no doubt that the salt contributes greatly to the aggravation and production of the dropsy, if not to the more serious symptoms. If the plain implications of the loss of appetite and repugnance to food were heeded and food abstained from, instead of forcing the appetite (not hunger) with salt, the dropsy would be readily eliminated and chemical balance restored in the body. The fact that sodium chloride has a paralyzing effect upon the activities of both the kidneys and the ureters has been known for more than fifty years.