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Cyclamate is an artificial sweetener, banned in the United States, but allowed as a tabletop sweetener in diet soft drinks and foods in other countries.
It is a controversial high-potency sweetener which was widely used in the United States in diet foods until 1970, at which time it was banned because animal studies suggested that it caused cancer. It is still permitted in Canada, Europe, and other Asian and African countries.
Now, based on animal studies, cyclamate is believed not to cause cancer directly, but to increase the potency of other carcinogens and to harm the testes.
Toxicity study of Cyclamate in Rats
Laboratory studies of the effect of Cyclamate on rats were conducted on a 10:1 cyclamate/saccharin (C/S) mixture to study the safety of it on rats compared to previous investigations which had established its safety.
The mixture was fed to groups of 35 male and 45 female rats. The observations of physical condition were growth response, food efficiency, blood, urine, and postmortem pathology. Reproduction and lactation performance was examined.
The only finding in these studies which proved to have crucial significance was the occurrence of papillary carcinomas in the bladders of 12 of the 70 rats fed the maximum dietary level of the mixture (equivalent to about 2500 mg/kg body weight) for periods ranging from 78 to 105 weeks (except for one earlier death).
This finding was the principal reason for the removal of cyclamates from the “generally recognized as safe” (GRAS) group of non-nutritive sweeteners by the U.S. Department of Health, Education and Welfare. In the opinion of the authors, the sequelae following this precipitate ban on cyclamates, prompted by a verbal report of the preliminary findings, warrant placing the study on record for the information of toxicologists and regulatory agencies throughout the world.
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