A team of researchers from the Ramazzini Institute claim that the sweetener sucralose, which is used in the popular brand Splenda, is linked to an increase in incidence of leukemia. Unfortunately, despite being reported in a few different publications, there is little evidence to back this claim up. In fact, the institute that apparently produced the results seemingly have a history of claiming to have evidence that other sweeteners such as aspartame also cause cancer, but refusing to divulge the data when requested by the European Food Safety Authority (EFSA).
The new study, published in the Journal of Occupational and Environmental Health, claims that their “findings do not support previous data that sucralose is biologically inert,” and instead that they “found a significant dose-related increased incidence of males bearing malignant tumors, and a significant dose-related increased incidence of [leukemia] in males.” They fail to mention in their conclusions that they only found “significant” increases in leukemia for those male mice given doses of sucralose at 2,000 parts per million (ppm) and 16,000 ppm, but not at an intermediate 8,000 ppm. Not only that, but female mice that were fed no sweetener as a control had almost the same rate of leukemia as the males being fed sucralose at 16,000 ppm. Cherry-picking, indeed.
According to Forbes, this isn’t the first time that the Ramazzini Institute in Bologna, Italy, has claimed that sucralose causes cancer, and it isn’t even the first time that they’ve caused concern over sweeteners. Previously, writes Forbes’ Trevor Butterworth, the institute declared that aspartame is carcinogenic, a claim that concerned the European Union’s Food Safety Authority to such a degree that they subsequently commissioned a panel of experts to examine the results. They found that the rats used in the experiment by the Ramazzini Institute probably already had the cancer the researchers claimed was a result of the aspartame.
It’s not the only aspect of the institute’s methodology that has been criticized either. In the recent study, for example, they fed the mice different doses of sucralose until the animals died of old age, and then looked at the different pathologies and histology of the subjects to see if they had increased incidences of cancer. This means that any cancers or illness that might be caused or exacerbated by old age are instead attributed to the amount of sweetener the animals are given.
Splenda has issued a response to the new study, stating that it “does not reflect the collective body of scientific evidence proving the safety of sucralose.” Not only that, but “health regulatory and food safety authorities have found other studies conducted by the Ramazzini Institute to be unreliable. The group routinely conducts studies using an unconventional design and has been criticized for not following internationally-recognized safety assessment standards.”
So it seems that the Ramazzini Institute does indeed have form, and it’s not good. But not only is it poor scientific method, it is also dangerous. The institute have been known to forego publishing their data in scientific journals and instead opt for issuing press releases before independent experts have analyzed their results, and even then they have been cagey about releasing their exact data. Unfortunately, this frequently leads to scaremongering and panic, despite a scientific consensus showing that sweeteners are indeed safe.