Aspartame defended by industry experts after cancer risk warning: 'Limited evidence'

On the heels of a WHO committee's labeling of aspartame as “possibly carcinogenic to humans," many industry experts are speaking out in defense of the sweetener.

Aspartame defended by industry experts after cancer risk warning: 'Limited evidence'

The World Health Organization (WHO) released its official statement this week on the potential health risks of aspartame, with a committee classifying the non-sugar, low-calorie sweetener as "possibly carcinogenic to humans."

Many industry experts, however, are speaking out in defense of aspartame, which is commonly used in diet sodas, chewing gum, some dairy products and many other low-calorie foods and beverages.

The International Agency for Research on Cancer (IARC), a cancer-focused organization within WHO, was the agency that called out the sweetener’s potential cancer risk.

The IARC uses five different levels of cancer risk: Group 1, "carcinogenic to humans"; Group 2A, "Probably carcinogenic to humans"; Group 2B: "Possibly carcinogenic to humans"; Group 3, "Unclassifiable as to carcinogenicity in humans"; and Group 4, "Probably not carcinogenic to humans."

Aspartame was placed in Group 2B based on "limited evidence" of causing cancer in humans and animals — particularly a type of liver cancer, the press release stated.

In the same announcement, the Joint Expert Committee on Food Additives (JECFA), another group within WHO, seemed to contradict the IARC’s classification.

"JECFA also considered the evidence on cancer risk, in animal and human studies, and concluded that the evidence of an association between aspartame consumption and cancer in humans is not convincing," the press release stated.

The acceptable daily intake (ADI) of aspartame remains 40 milligrams per kilogram of body weight, JECFA also said. That amount is the equivalent of nine cans of 12-ounce diet soda per day for a 150-pound person.

(The FDA recommends an even higher ADI, at 50 milligrams per kilogram of body weight.)

"Our results do not indicate that occasional consumption should pose a risk to most consumers," Dr. Francesco Branca, director of the Department of Nutrition and Food Safety at the WHO, stated during a press conference in Geneva.

Dr. Mona S. Jhaveri, a biotech scientist and cancer researcher in Ridgefield, Connecticut, told Fox News Digital that the likelihood of getting cancer depends on the types and the number of carcinogens that one is exposed to, as well as genetic factors. 

"Carcinogens can work either alone or in combination with other substances," she said. 

Often, she added, "people who are subject to multiple carcinogens can increase their risk of getting cancer exponentially."

Many industry experts maintain that aspartame is still safe for consumption — including the FDA, which released a statement refuting the cancer risk.

"The FDA disagrees with IARC’s conclusion that these studies support classifying aspartame as a possible carcinogen to humans," the statement read. 

"FDA scientists reviewed the scientific information included in IARC’s review in 2021 when it was first made available and identified significant shortcomings in the studies on which IARC relied."

"We note that JECFA did not raise safety concerns for aspartame under the current levels of use and did not change the acceptable daily intake (ADI)."

Additional agencies, including the European Food Safety Authority and Health Canada, have also deemed aspartame to be safe at the current recommended levels, the FDA added.

"Aspartame is one of the most studied food additives in the human food supply," the FDA stated. 

"FDA scientists do not have safety concerns when aspartame is used under the approved conditions."

Dr. Arnold Baskies, a New Jersey-based surgical oncologist and past chairman of the National Board of Directors of the American Cancer Society — he's also a member of the Coalition for Safe Food and Beverage Choices Expert Advisory Committee — pointed out that the WHO agencies, IARC and JECFA, reviewed previous research. They did not review new evidence.

"The WHO Joint Expert Committee on Food Additives’ (JECFA) review says that aspartame is safe for human consumption," Baskies said in a statement provided to Fox News Digital. "JECFA is the authoritative international agency when it comes to food safety."

The FDA relies on JECFA’s assessments as part of its process of determining the safety and risks of foods and beverages, Baskies noted.

"It is irresponsible to needlessly scare or confuse people," he said. "If there was any cause for concern, they would have adjusted the current acceptable daily intake (ADI)."

The Calorie Control Council (CCC) in Atlanta, Georgia, also spoke out in defense of aspartame as a safe food additive.

"The JECFA ruling not only confirms the four decades of science concluding aspartame is safe, but also provides real-life ‎context around the safe consumption of this ingredient," said Robert Rankin, president of the CCC, in a statement sent to Fox News Digital.

Any risk is highly unlikely given the JECFA’s guidelines for recommended daily intake, Rankin also said.

"The average 150-pound person would need to consume about 14 12-oz. cans of diet beverages or about 74 packets of aspartame-containing tabletop sweetener every day over the course of their life to raise any safety concern," Rankin said.

"Obviously, that level of consumption is not realistic or recommended, nor is it ‎aligned with the intended use of these ingredients."

Regarding IARC describing aspartame as "possibly cancer-causing," Rankin stated that IARC is not a regulatory agency or food safety authority, and said that its classification is "misleading, inaccurate and [constitutes] fearmongering."

He said, "IARC looks for substances that could potentially cause cancer without considering actual dietary intake, and has found many things, such as drinking hot water and working at night, to be probably carcinogenic."

"It is not only wrong, but potentially damaging to certain populations to position IARC’s report alongside true scientific and regulatory agencies like JECFA, the Food and Drug Administration, and the European Food Safety Authority," Rankin added.

Dr. Ernest Hawk, head of the Division of Cancer Prevention and Population Sciences at The University of Texas MD Anderson Cancer Center, also spoke to Fox News Digital about aspartame’s safety.

"IARC classified aspartame as ‘possibly carcinogenic to humans’ based on limited evidence for cancer in humans and experimental animals, and limited evidence that it might behave as a carcinogen," he said. 

"Because all of the evidence was limited, aspartame was added to WHO’s list of possible carcinogens."

The list begins with 126 agents known to be carcinogenic in humans (including tobacco and alcohol) and 94 agents that are "probably carcinogenic" — followed by 322 agents that are "possibly carcinogenic," Hawk explained.

"Aspartame will now be included in that final group, but keep in mind that none of those have been convincingly proven to cause cancer," he added.

The FDA, the National Cancer Institute, the American Institute for Cancer Research and the American Cancer Society all have evaluated the same evidence in the past, and all of them concluded that there was no clear evidence that artificial (non-nutritive) sweeteners cause cancer when consumed at typical levels, Hawk said.

While he believes that the WHO agencies did a careful review and have the public’s best interest in mind, Hawk called for additional research on the long-term health risks of consuming non-sugar sweeteners.

The FDA and other health agencies do not agree that aspartame is a cancer risk, so some medical professionals recommend using sugar instead of artificial sweeteners.

"Although it’s approved by regulatory bodies, potential risk factors are associated with preferring aspartame over sugar," noted Jhaveri.

"Sensitivities or allergies to aspartame can result in adverse reactions, and excessive consumption may contribute to weight gain due to heightened cravings for sweet edibles," she said.

For some people, aspartame may cause physical symptoms that include headaches, dizziness, digestive ailments and allergic responses, Jhaveri noted.

"Avoiding aspartame when possible and opting for natural sugars in fruits and vegetables is prudent," she said. 

In May, the WHO advised against the use of non-sugar sweeteners like aspartame for the purposes of controlling body weight or lowering the risk of non-communicable diseases.

"Replacing free sugars with NSS does not help with weight control in the long term," said Branca, the WHO’s director for nutrition and food safety, in a press release at the time. 

For the general public, Hawk recommended "paying attention to the science" as it continues to develop regarding the possible health consequences of artificial sweeteners.

"In the meantime, continue to work on consistently eating a balanced, healthy diet that contains whole foods that are high in nutrient density," he suggested.

People with a rare inherited disorder called phenylketonuria (PKU) should avoid aspartame, medical experts say.

Those with PKU don’t have the enzyme to break down an amino acid called phenylalanine, so it builds up in the body. 

Consuming foods and drinks with aspartame can cause dangerous levels of phenylalanine that can lead to serious health issues, according to the Mayo Clinic’s website.

Aspartame-containing products will include a warning on the label stating "PHENYLKETONURICS: CONTAINS PHENYLALANINE." 

Anyone with PKU should avoid any food or drink with this warning.