FDA Says Aspartame Is Safe, Despite Warning by WHO

The US Food and Drug Administration (FDA) says that the artificial sweetener, aspartame, is safe, disagreeing with the World Health Organization’s (WHO) conclusion that it is a possible human carcinogen.

The agency refutes the assessment from the WHO’s International Agency for Research on Cancer (IARC) and Joint Expert Committee on Food Additives (JECFA) released Friday, classifying aspartame as possibly carcinogenic to humans.

The FDA says its scientists found "significant shortcomings" in the studies on which the IARC’s review relied. Additionally, the agency underscores that current levels of aspartame use are considered safe by the JECFA.

"Scientific evidence continues to support its conclusion aspartame is safe for the general population when made under good manufacturing practices and used under the approved conditions of use," the FDA states on its website.

However, people with difficulty metabolizing phenylalanine because of a rare genetic disorder called phenylketonuria (PKU) should avoid or restrict aspartame.

Both sugar and aspartame have about four calories per gram, but aspartame is 180 to 200 times sweeter. It is added to sodas, confectionery, gum, and other products to reduce sugar consumption.

The WHO’s assessment that created an international uproar is based on limited evidence for cancer in humans, specifically hepatocellular carcinoma, which is a type of liver cancer. The report emphasizes the need for more research on whether aspartame consumption poses a carcinogenic hazard.

Meanwhile, the JECFA concludes that aspartame is safe to consume in substantial quantities daily. For example, an adult weighing about 150 lbs (70 kg) would need to consume more than nine to 14 cans of soft drinks to go beyond the recommended intake, assuming there was no intake from other sources.

In May, the WHO recommended against using artificial sweeteners, including aspartame, saccharin, sucralose, and stevia, saying long-term consumption might lead to type 2 diabetes, cardiovascular diseases, and premature death.