Sugar is looking awfully healthy after recent research found that the "no calorie sweetener" Splenda raises the risk of blood cancers. The research, conducted at the Ramazzini Institute in Italy, revealed that the active ingredient in Splenda, called sucralose, significantly increased the risk of leukemia.

The latest study, which involved 457 male mice and 396 female mice who were fed different amounts of sucralose, revealed that the artificial sweetener significantly increased the risk of leukemia and other cancers in male mice.

"We found a significant dose-related increased incidence of males bearing malignant tumors and a significant dose-related increased incidence of hematopoietic neoplasias in males, in particular at the dose levels of 2,000 ppm and 16,000 ppm," they added.

For the experiment, researchers split mice into five different groups according to concentrations of sucralose at zero; 500; 2,000; 8,000; and 16,000 ppm. The mice were fed the artificial sweetener through their lifespan from 12 days of gestation.

"These findings do not support previous data that sucralose is biologically inert. More studies are necessary to show the safety of sucralose, including new and more adequate carcinogenic bioassay on rats. Considering that millions of people are likely exposed, follow-up studies are urgent," researchers concluded in their study published in the International Journal of Occupational and Environmental Health.

The findings have triggered activist groups to warn consumers against using the artificial sweetener.

This is not the first time Splenda has come under spotlight. Splenda's safety was downgraded from "safe" to "caution" in 2013 by the Center for Science in the Public Interest after the artificial sweetener was linked to cancer for the first time. The latest findings have prompted the food safety and nutrition watchdog group to issue another safety downgrade from "caution" to "avoid".

"We recommend that consumers avoid sucralose, or Splenda, and we recommend consumers also avoid saccharin, aspartame, and acesulfame potassium," CSPI president Michael F. Jacobson said in a recent statement.

"That said, the risk posed by over-consumption of sugar and high-fructose corn syrup, particularly from soda and other sugar-sweetened beverages, of diabetes, heart disease, and obesity, far outweighs the cancer risk posed by sucralose and most other artificial sweeteners. Consumers are better off drinking water, seltzer, or flavored waters, but diet soda does beat regular soda," he concluded.