Calcium cyclamate was a widely used artificial sweetener in the 1970s, commonly used in diet soft drinks. However, in 1969, studies on rats showed that high doses of cyclamate caused cancer in the bladder, and testes. As a result, the US Food and Drug Administration (FDA) banned the use of cyclamate in food and beverages in 1969.
This ban also extended to calcium cyclamate, which was a salt form of cyclamate. Because of this ban, it is no longer used as a sweetener in soda or any other food products in the United States. However, it should be noted that the studies done on rats were done with very high dosages of cyclamate and the International Agency for Research on Cancer (IARC) has classified it as a possible human carcinogen, though it is still widely used in some countries.