The New York Times reported that World Health Organization (WHO) has declared that aspartame, an artificial sweetener used in diet drinks and low-sugar foods, could possibly cause cancer. This is the first time that the WHO has publicly weighed in on the effects of aspartame.
The International Agency for Research on Cancer (IARC), a division of the WHO, based its conclusion on limited evidence from three observational studies that linked the consumption of artificially sweetened beverages to an increase in liver cancer.
However, a second WHO committee maintained its assessment of a safe level of aspartame consumption, stating that occasional consumption should not pose a risk to most individuals. The US Food and Drug Administration (FDA) criticized the global agency’s findings and reiterated its position that aspartame is safe.
Aspartame, one of six sweeteners approved by US regulators, is found in numerous products, including diet sodas, low-sugar yogurts, sugar-free gum, teas, and energy drinks. Concerns about rising rates of obesity and diabetes have led to an increase in no- and low-sugar food and beverages. However, aspartame has been a contentious ingredient for decades.
The IARC concluded that aspartame was a possible carcinogen based on limited evidence from observational studies, which linked consumption of artificially sweetened beverages to an increase in cases of liver cancer. The agency cautioned that the results could be influenced by the profile of people who drink higher amounts of diet drinks and called for further study. The IARC recommended that people who consume high amounts of aspartame consider switching to water or other unsweetened drinks.
The FDA disagreed with the IARC’s conclusion, stating that aspartame is safe and that the studies cited by the IARC do not support classifying aspartame as a possible carcinogen to humans. The FDA declined to provide further comment on its concerns.
The conflicting positions of the global agencies are likely to fuel confusion among consumers. The American Beverage Association, which represents major beverage companies like Coca-Cola and PepsiCo, emphasized the WHO’s second committee’s assessment that people can safely consume moderate amounts of aspartame. The industry has long fought against any regulatory or scientific findings linking artificial sweeteners to health risks.
Aspartame has been the subject of debate and research, with some studies suggesting a link to cancer in animals. However, the FDA has dismissed these studies as compromised. Other sweeteners have also faced scrutiny for potential health risks. The safety of sugar replacements has been heavily scrutinized, with saccharin, once linked to bladder cancer in rats, later being removed from the list of potential carcinogens.
The WHO’s cancer agency has four categories for evaluating substances: carcinogenic, probably carcinogenic, possibly carcinogenic, and no classification. The designation reflects the strength of the scientific evidence rather than the likelihood of causing cancer. Aspartame has been categorized as “possibly carcinogenic to humans” by the IARC.
The beverage industry trade group has financed a coalition led by former secretaries of the Department of Health and Human Services to support the FDA’s position on the safety of aspartame. The trade group had previously contested a review of aspartame’s potential links to cancer in California.
While the WHO’s assessment raises concerns about aspartame, more research is needed to determine the full extent of the potential risks. The science is clearer on reducing cancer risk by avoiding tobacco, alcohol, and processed meat, and maintaining a healthy body weight.