Chemical Cuisine Rating


Purpose: Artificial Sweetener

Health Concerns: Cancer 

Found in: "No sugar added," "sugar-free," "diet" and other products, including baked goods, kettle corn, frozen desserts, ice cream, soft drinks, prepared meals, packaged (tabletop) sweeteners (Splenda)


Approved in the United States in 1998, sucralose—sometimes marketed as Splenda—is used in soft drinks, baked goods, ice cream, and other products, including ones you might not expect, such as frozen dinners and English muffins. It is widely used around the world. Unlike aspartame, sucralose does not break down at high temperatures and so can be used in baked goods.

In 2016 an independent Italian laboratory published a large study on mice. The study found that sucralose caused leukemia and related blood cancers in male mice that were exposed to it throughout their lives starting from before birth. The study is superior to previous industry-sponsored studies that did not find a link with cancer, since those tested fewer animals, started exposing the animals much later, and terminated the study earlier. In addition, treated animals in the industry-sponsored studies had significantly decreased body weight compared to controls, which can decrease cancer rates. This Italian lab is the same one that several years earlier published studies that found that aspartame caused cancers in rats and mice.

When sucralose was first being considered for approval by the FDA, CSPI objected. A study in rats had indicated that the additive might cause premature shrinkage of the thymus gland, which is part of the immune system. However, a subsequent study did not find any problem. Likewise, studies designed to detect whether sucralose could cause cancer in lab animals did not find any problems.

Several researchers contend that sucralose negatively impacts the gut, including changes in the microbiome and enzymes. That could have a range of consequences, including effects on blood sugar, regulation of body weight, inflammatory bowel disease, and how drugs and other chemicals are absorbed and metabolized by the body. For example, a 2008 study (funded by the sugar industry) reported that Splenda significantly reduced beneficial bacteria and had other effects in the gastrointestinal tract of rats that could affect the bioavailability of drugs. Unfortunately, the study was small and had other significant shortcomings. Meanwhile, people experiencing IBD or other GI symptoms could see if avoiding sucralose provides any relief.

Even setting aside these concerns, young children could exceed the FDA’s “acceptable daily intake” for sucralose (5 mg/kg), especially given sucralose’s popularity (more products containing sugar substitutes use sucralose than any other sweetener). For example, a 6-year old child weighing 45 pounds would exceed the FDA limit by drinking two or three 12-ounce sodas containing the typical 40-60 mg of sucralose per can. In addition, sucralose passes into breast milk at levels high enough to make the milk sweeter.

A final point: McNeil Nutritionals long advertised Splenda as being “made from sugar, so it tastes like sugar.” That statement may be literally true, but is misleading, as the Sugar Association charged in a lawsuit. In fact, the sweetener is a synthetic chemical made by chemically reacting sugar (sucrose) with chlorine. (The mere fact that sucralose is synthetic does not make it unsafe.) The lawsuit was settled without any announcement of the terms, but McNeil has dropped that “made from sugar” slogan.

See our comprehensive Chemical Cuisine ratings of more than 150 food ingredients and additives.

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