Artificial sweeteners reduce added sugar content and corresponding calories while maintaining sweetness. Charlotte Debras and Mathilde Touvier of the French National Institute of Health and Medical Research (Inserm) and the Sorbonne Paris Nord University and colleagues published a study in Public Library of Science – A study published in PLOS Medicine suggests that some artificial sweeteners are associated with an increased risk of cancer.

Millions of people consume these foods and beverages containing artificial sweeteners every day, however, the safety of these additives has been controversial. To assess the potential carcinogenicity of artificial sweeteners, researchers analyzed data from 102,865 French adults enrolled in the NutriNet Santé study, a web-based cohort study initiated by the Epidemiology Research in Nutrition (EREN) team in 2009. Participants voluntarily enrolled and self-reported medical history, sociodemographic, dietary, lifestyle, and health data.

Researchers collected data on artificial sweetener intake from 24-hour dietary records. After collecting cancer diagnosis information during follow-up, the researchers conducted statistical analyses to investigate the association between artificial sweetener intake and cancer risk. They also adjusted for a range of variables, including age, sex, education, physical activity, smoking, body mass index, height, weight gain during follow-up, diabetes, family history of cancer, and baseline intake of energy, alcohol, sodium, saturated fatty acids, fiber, sugar, whole grain foods, and dairy products.

The researchers found that subjects who consumed large amounts of artificial sweeteners (especially aspartame and acetylsulfamethonyl-K) had a higher risk of cancer compared with nonusers (risk ratio 1.13, 95% confidence interval 1.03 to 1.25). The risk of breast and obesity-related cancers was higher.

This study has several important limitations; dietary intake was self-reported. Selection bias may also have been a factor, as participants were more likely to be female, have higher levels of education, and exhibit health-conscious behaviors. The observational nature of this study also means that residual confounding is possible and reverse causation cannot be ruled out. Further research is needed to confirm these findings and elucidate the underlying mechanisms.

According to the authors, the results of this study do not support the use of artificial sweeteners as a safe alternative to sugar in food or beverages and provide important and novel information to address the controversy regarding their potential adverse health effects. While these results need to be replicated in other large-scale cohorts and the underlying mechanisms elucidated through experimental studies, they provide important and novel insights into food additive sweeteners that are being re-evaluated by the European Food Safety Authority and other health authorities worldwide.

The study authors added: “Results from the NutriNet-Santé cohort (n=102,865) suggest that artificial sweeteners found in many food and beverage brands around the world may be associated with an increased risk of cancer, consistent with several in vivo/in vitro experimental studies. These findings provide new information for health authorities to re-evaluate these food additives.”