Millions of people consume sweeteners every day in products like diet sodas, in part as a way to avoid weight gain from sugar, but the health of these substitutes has long been a matter of controversy.
To assess cancer risk from sweeteners, researchers analyzed data from more than 100,000 people in France who reported their diet, lifestyle and medical history at intervals between 2009 and 2021 as part of the nutrient-Sante study.
They then compared consumption to cancer rate, while adjusting for other variables such as smoking, poor diet, age and physical activity.
The participants who consumed the highest amount of sweeteners, “beyond the average amount, had a 13% increased risk of cancer compared to non-consumers,” Mathilde Touvier, director of research at the French institute INSERM, told AFP. and studio supervisor.
The study, published in the journal PLOS Medicine, said an increased risk of cancer was seen particularly with the sweeteners aspartame and acesulfame potassium, both of which are used in many soft drinks, including Coca-Cola Zero.
Of the 103,000 participants, 79% were women and 37% consumed artificial sweeteners.
Soft drinks accounted for more than half of the artificial sweeteners consumed, while tabletop sweeteners accounted for 29%.
The study found that “increased risks of breast cancer and obesity-related cancers were observed.”
Touvier said that “we cannot exclude biases related to consumers’ lifestyle,” calling for more research to confirm the study’s results.
The US National Cancer Institute and Cancer Research UK state that sweeteners do not cause cancer and have been authorized for use by the European Food Safety Authority.
“The relationship between artificial sweetener consumption and cancer risk is controversial and dates back to the 1970s when cyclamate (sweetener) was banned for being linked to bladder cancer in rats, although it was never shown to be the case in humans,” he said. said James Brown, a biomedical scientist at Britain’s Aston University.
Brown, who was not involved in the study, told AFP it was “reasonably well designed” and had an “impressive” sample size.
But he added that he did not “believe the current study provides strong enough evidence” for Britain’s National Health Service to “change its advice yet”.
Michael Jones of the Institute of Cancer Research in London said the link reported in the study “does not imply causation” and “is not proof that artificial sweeteners cause cancer.”
He said the findings might suggest that “cancer risk might be increased in the type of person who uses artificial sweetener rather than the sweetener itself.”
Thursday’s findings don’t mean consumers should go back to sugary drinks, either: A 2019 NutriNet-Sante study found they were also linked to an increased risk of several types of cancer.
Brown said that not all sweeteners were created equal and that some, such as stevia, showed health benefits.
Artificial sweeteners “are still probably a useful tool that can help reduce weight gain by replacing sugar, if the right sweetener is used,” he said.