Splenda, a popular artificial sweetener, may cause stomach pains and other digestion problems and should be pulled from the U.S. market until more research can be done to assess its safety, consumer advocates said on Monday.

In a petition to the U.S. Food and Drug Administration, Citizens for Health asked the agency to withdraw its approval of the zero-calorie sugar substitute pending further investigation of possible side effects.

Splenda is owned by Johnson & Johnson’s McNeil Nutritionals unit and manufactured by Tate & Lyle Plc.

Hundreds of consumers and doctors have told the group about severe stomach pain and other gastrointestinal trouble, said Jim Turner, a lawyer and board chairman of Citizens for Health. He also told reporters at a news conference most felt better a month after discontinuing Splenda.

“This is not a product that has any kind of relevance to sugar. It is an artificial sweetener created with a powerful chemical,” said Turner, whose group is funded by consumer members and health food makers and retailers.

But Tate & Lyle said the petition is an attempt to thwart Splenda’s commercial success.

“The simple fact about sucralose is that there is no evidence that it causes any side effects whatsoever. This is why a safety statement or warning label has never been required,” it said.

Splenda, the latest mass-marketed artificial sweetener aimed at consumers looking to control their diet or sugar intake, has been sold in the United States since 1998. It contains sucralose, a chemically altered version of sugar that replaces naturally found hydrogen and oxygen with chlorine.

A number of soft drinks, snack foods and other products also contain Splenda, which is 600 times sweeter than sugar.

Other FDA-approved artificial sweeteners, including aspartame and saccharin, have also faced controversy over potential health risks. The FDA has said it stands behind those products but constantly monitors for safety issues.

Eighty-four percent of Americans use sugar substitutes or products containing them, according to the industry group Calorie Control Council.

Splenda is a key product for Tate & Lyle, accounting for about 20 percent of the company’s profit. The London-based ingredient maker controls sales to food and drink makers while McNeil sells the product to retailers.

Recent competition from Wal-Mart Stores Inc., which began selling its own sweetener, Altern, in February, have threatened Splenda and put pressure on Tate’s shares.

McNeil Nutritionals said more than 100 studies have found sucralose safe. But Citizens for Health said studies in people were never conducted with Splenda.

Laura Tarantino, director of the FDA’s Office of Food Additive Safety, said there is a reporting system for food-related problems but it showed no evidence of a Splenda trend.

“It is very difficult to track these (problems) because when someone eats something and then has a stomach ache it’s very difficult for anybody to know what it relates back to,” she said.

Tarantino said she planned to review the petition but had not yet seen it.