Safety of sucralose:
Grotz VL and Munro IC performed an overview of sucralose and stated that collective evidence supports that it is safe (5), and no gastrointestinal side effects were seen in studies.
Saccharin:
Saccharin is also known as “Sweet N Low,” and is on average, 450 times sweeter than sugar.
Saccharin and cancer:
Saccharin may cause urinary tract tumors (bladder cancer) in humans but this is unclear because the study grouped the 3 artificial sweeteners; saccharin, aspartame, and acesulfame together when subjects were asked to report consumption of all artificial sweeteners. (1)
Saccharin in animal studies:
Studies have shown that rats developed urinary tract tumors but this was not demonstrated in mice, hamsters, or monkeys. As of 1990, there was no clear evidence of saccharin causing cancer in humans. (7)