After years of warning consumers to use Splenda with caution, a consumer advocacy group has changed its position. The Center for Science in the Public Interest now says people shouldn't use Splenda at all.

The toughening of the consumer group's stance comes after publication of a study that said sucralose, the sweetener sold as Splenda, gave male mice leukemia and other blood cancers.

The study was published Jan. 29 in the peer-reviewed International Journal of Occupational and Environmental Health. Its findings had been previously released at a conference in 2013, causing the CSPI to change its earlier "safe" rating to "caution."

That announcement, however, was widely met by skepticism. Forbes magazine called the lead scientist "controversial" and said the Ramazzini Institute, which has also produced studies indicting aspartame, is "something of a joke in European and American science."

"No matter what substance the Institute tests for cancer, the results always seem to be positive, whereas other laboratories testing the same substances repeatedly fail to come up with the same findings," Trevor Butterworth wrote for Forbes.

Other studies, however, have found that Splenda and other sweeteners don't heighten the risk of cancer, and the Food and Drug Administration says it reviewed 110 studies before deeming it safe for consumption.

In January, CNN surveyed the latest research on all types of sweeteners and concluded that "those pink, blue and yellow packets are probably fine — for now."

CNN said studies that suggest a heightened risk of kidney decline and vascular trouble bear watching, and noted that sweeteners are not approved for unlimited use. (Although it seems doubtful that many people are using dangerous levels of Splenda, which is more than 23 packets a day.)

"So where does this leave us?" CNN's Sandee LaMotte asked. "The FDA feels you can be pretty darn sure that a moderate dose of the artificial stuff won't give you cancer. If you're a heavy consumer — and that's a lot of sweetener — that's another story."

The mice in the Ramazzini study were heavy consumers. They were fed sucrolose all of their lives, beginning in utero, The Center for Science in the Public Interest said.

Regardless, it renewed its call for Americans to shun not only sucralose, but other sweeteners, including saccharin, aspartame and acesulfame potassium.

It admits, however, that there's something even worse than artificial sweeteners: sugar.

"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," CSPI president Michael Jacobson said in a news release.

The manufacturers of Splenda did not comment on the center's announcement. Visitors to Splenda's Facebook page Monday got a recipe for tomato jam and learned how to make "roses" out of strawberries. The company is busy promoting Splenda as the only sweetener made completely in the U.S., and it is redesigning its yellow packets with a stars-and-stripes motif that will be available before Independence Day.

EMAIL: Jgraham@deseretnews.com

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