“Sugar-free drinks cause cancer in humans.”

The results of these studies showed no evidence that these sweeteners cause cancer or other harms in people. At a June 2023 meeting, an international expert working group classified aspartame as Group 2B, “possibly carcinogenic to humans.” This category is used when there is limited, but not convincing, evidence for cancer in humans or convincing evidence for cancer in experimental animals, but not both.

Citing “limited evidence” for carcinogenicity in humans, IARC classified aspartame as possibly carcinogenic to humans (IARC Group 2B) and JECFA reaffirmed the acceptable daily intake of 40 mg/kg body weight. The assessments of aspartame have indicated that, while safety is not a major concern at the doses which are commonly used, potential effects have been described that need to be investigated by more and better studies.

The World Health Organization's (WHO) cancer research agency on Friday classified the commonly used artificial sweetener aspartame as “possibly carcinogenic to humans”, although another UN committee reaffirmed that there was a safe daily level of consumption. IARC classified aspartame as possibly carcinogenic to humans (Group 2B) on the basis of limited evidence for cancer in humans (specifically, for hepatocellular carcinoma, which is a type of liver cancer).

The findings of this umbrella review do not support a significant association between artificial sweetener intake and overall cancer risk, with possible protective effects limited to gynecological cancers. Findings were consistent across study types and robust to sensitivity analyses. By sweetener source, no significant associations emerged for artificially sweetened beverages (RR: 0.98; 95% CI: 0.96-1.01) or artificial sweeteners overall (RR: 1.00; 95% CI: 0.94-1.06), both with low heterogeneity.

IARC is the cancer research agency of the WHO. One of its major roles is to identify causes of cancer. IARC classifies aspartame as “possibly carcinogenic to humans” (Group 2B), based on limited evidence it might cause cancer (specifically liver cancer) in people. JECFA has concluded that “the evidence of an association between aspartame consumption and cancer in humans is not convincing.”

In this large cohort study, artificial sweeteners (especially aspartame and acesulfame-K), which are used in many food and beverage brands worldwide, were associated with increased cancer risk. More specifically, aspartame intake was associated with increased breast (HR = 1.22 [95% CI 1.01 to 1.48], P = 0.036) and obesity-related (HR = 1.15 [95% CI 1.01 to 1.32], P = 0.026) cancer risks.

Importantly, the majority of research data show no link between the use of artificial sweeteners and cancer risk. Although most studies show that there is no established link between these products and cancer risk, artificial sweeteners are associated with multiple diseases.

We found no consistent associations between any NSS or NSSs in aggregate and any cancer overall, and no evidence for dose-response. ... Overall, the epidemiology evidence does not support associations between any NSS and any cancer type.

There is limited evidence to suggest that the artificial sweetener, aspartame, often used in 'low-sugar' and 'diet' drinks, and other products like confectionery, and yoghurt, causes cancer. The World Health Organisation's International Agency on Research on Cancer classified aspartame, as 'possibly carcinogenic to humans'. This is based on limited evidence that consumption of aspartame is associated with an increased risk of liver cancer.

A new study has found that patients with melanoma and non-small cell lung cancer who consumed high levels of sucralose - a widely used artificial sweetener - had worse response to immunotherapy and poorer survival than those with diets low in the artificial sweetener. The research, conducted by the University of Pittsburgh and UPMC Hillman Cancer Centre, suggests that the artificial sweetener may not be the best choice for patients undergoing cancer immunotherapy.

Put simply, artificial sweeteners found in diet sodas have not been proven to cause cancer, but they don't offer any nutritional value either. In addition, scientists are still researching the possible health implications of artificial sweeteners, including whether they can increase cancer risk. But more research is needed.

Artificial sweeteners in fizzy, diet or zero-sugar drinks won't increase your risk of cancer. There is no strong evidence that artificial sweeteners cause cancer. The best studies of people do not show a link between artificial sweeteners and cancer.

The WHO's reclassification of aspartame from its lowest level of risk (Group 3 – not classifiable as to its carcinogenicity to humans) to its Group 2B level (possibly carcinogenic to humans) indicates only that there is a clear need for further, high-quality research on non-sugar sweeteners and their possible long-term health implications. There's no convincing evidence that either using or avoiding sugar and non-sugar sweeteners can adversely impact either cancer development or its responsiveness to treatment.

The evidence that aspartame causes cancer is not strong, so the harm is likely to be low. The new reports have categorised aspartame as “possibly carcinogenic to humans” and given it an evidence grading level known as 2B. The evidence for a direct link between aspartame and cancer is not strong.

Saccharin received a bad rap after studies in the 1970s linked consumption of large amounts of the artificial sweetener to bladder cancer in laboratory rats. Later, research revealed that these findings were not relevant to people. And in a complete turnabout, recent studies indicate that saccharin can actually kill human cancer cells.

A determination by top cancer authorities will rule that aspartame, a common sweetener in sodas and food, is “possibly carcinogenic to humans,” according to sources familiar with the expected announcement. The decision was made by the International Agency for Research on Cancer, or IARC, an arm of the World Health Organization.