No, Aspartame Doesn’t Cause Cancer – The American Spectator

Unlax, doc! You can still order that double cheeseburger with super-duper fries and a Diet Coke to top it off. There’s no good evidence that the sweetener used in the numerous variations and names applied to sugar-free Coke products causes cancer. Not really any bad evidence, either. This despite a slew of articles a few weeks ago and then last week claiming that a well-known agency, the International Agency for Research on Cancer (IARC), would declare otherwise (with such claims as “Aspartame sweetener to be declared possible cancer risk by WHO, say reports” and “Aspartame is a “possible” cause of cancer”).

And indeed, it did just classify it as a 2B: “possibly carcinogenic to humans.” No, you haven’t already seen this article. You’re thinking of one I recently published in these pixels about a different artificial sweetener — sucralose, sold under the brand name Splenda — that appears harmless, and, anyway, those accusations didn’t include cancer.

This time it’s aspartame, brand names of NutraSweet, Equal, Sugar Twin, and some more. It’s used in a large variety of products composing Diet Coke (including the vanilla flavor I just discovered and really like that also contains another artificial sweetener called acesulfame potassium), ice cream, chewing gum, cereals, puddings, sugar-free desserts, sugar-free jams, and various other low-sugar or sugar-free packaged food.

I thought of striking back at all those naysaying articles then but decided to wait for the IARC’s report, plus an accompanying one, to actually appear. Do you know the blogger “Instapundit”? I like to think of myself as “Thoughtfulpundit.”

Aspartame Is Still Widely Considered Safe

Let’s start with this. Aspartame has been deemed safe for human consumption by more than 100 regulatory agencies in their respective countries, including:

• The U.S. Food and Drug Administration (FDA)
• The European Food Safety Authority (EFSA)
• Health Canada
• The Food Standards Agency (UK)
• Food Standards Australia New Zealand

(I got the 100 citations from Wikipedia’s entry, and as a rule, I don’t cite Wikipedia, but I do look at their individual citations, and it checks out.) 

Here is the FDA’s information page, current to May 30 of this year:

Aspartame is one of the most studied food additives in the human food supply. To determine the safety of aspartame, the FDA has reviewed more than 100 studies designed to identify possible toxic effects, including studies that assess effects on the reproductive and nervous systems, carcinogenicity, and metabolism. FDA scientists reassessed the science on the exposure and safety of aspartame in food each time the agency filed a food additive petition, received relevant information from other regulatory agencies and research institutions that have evaluated aspartame, and responded to objections that were raised related to the approved uses of aspartame.

The FDA added that “[s]ince the last approved use in 1996, the FDA has continued monitoring the scientific literature for new information on aspartame.” Other regulatory agencies have evaluated aspartame, and it is approved in many countries. To cite one such, the EFSA has stated, “Studies do not suggest an increased risk associated with aspartame consumption for … leukemia, brain tumors or a variety of cancers, including brain, lymphatic and hematopoietic (blood) cancers.”

The ‘You’ll-Never-Be-Proven-Innocent’ Approach

But what’s up with the IARC?

The IARC’s rulings can have a huge impact, notes the Canadian Broadcasting Corporation: “In 2015, its committee concluded that glyphosate is ‘probably carcinogenic.’” Years later, even as other bodies like EFSA contested this, companies were still feeling the effects of the decision. Germany’s Bayer weed killer lost its third appeal in 2021 against U.S. court verdicts, which awarded damages to customers blaming their cancers on the use of its glyphosate-based weed killers. (READ MORE: Unveiling Liberal Indoctrination in Therapy Rooms: The Four Toxic Ideas Crippling Mental Health)

I have repeatedly been among the critics, including in an article regarding glyphosate in these pixels.

The IARC has four tiers for suspected carcinogenicity:

• Group 1: “Carcinogenic to humans” (This group includes substances or exposures that have sufficient evidence of causing cancer in humans. Examples include tobacco smoke, asbestos, and UV radiation.)
• Group 2A: “Probably carcinogenic to humans”
• Group 2B: “Possibly carcinogenic to humans” (An example includes coffee.)
• Group 3: “Not classifiable as to its carcinogenicity to humans” (This includes substances or exposures for which there is inadequate evidence to determine their carcinogenicity in humans.) 
• Group 4: “Probably not carcinogenic to humans”

Nothing gets rated “non-carcinogenic to humans.” It’s not just guilty-until-proven-innocent, which around the world is actually much more common even in criminal law than the American standard, it’s you’ll-never-be-proven-to-be-innocent.

“Of all the agents that IARC have classified over the years, just over a thousand of them, half are currently classified in group 3,” says Kevin McConway, professor emeritus of applied statistics at the Open University in Milton Keynes near London. “Often this will simply be because of lack of good evidence, or sometimes because different pieces of evidence point in different directions,” he told a useful website called Science Media Centre. “But there can be other sets of reasons for allocating an agent to group 3 — basically it includes any agent where IARC did not find enough evidence to conclude even a possibility that it might cause cancer in humans.”

But wait! There’s more! That is, about how the IARC operates.

Geoffrey Kabat, cancer epidemiologist and author of Getting Risk Right: Understanding the Science of Elusive Health Risks, devoted an entire 4,000-word essay in Issues in Science and Technology to explain why the IARC’s assessment is used. One aspect is that, unlike virtually all other agencies, the IARC does hazard assessment rather than risk assessment. 

“This means that IARC considers any scientific evidence of possible carcinogenicity, no matter how difficult to interpret or how irrelevant to actual human exposure,” says Kabat. In so doing, the IARC ignores the most basic rule of toxicology, that “the dose makes the poison.” Of course, if the safest classification is “probably not,” then, inherently, it also means “possibly so.”

Kabat demonstrated a litany of problems specific to the IARC evaluation of glyphosate, showing that it simply ignored a huge glyphosate study from the National Cancer Institute–funded Agricultural Health Study (AHS) of 54,000 pesticide applicators in Iowa and North Carolina because it hadn’t yet been put in print. Well, it has been now and still shows no association.

Also, with glyphosate, the IARC relied on rodent studies that showed no consistent or robust evidence of increased tumors in exposed animals; however, by selecting “a few positive results in one sex and [using] an inappropriate statistical test,” it found some significant tumor increases, Kabat wrote. “Salami slicing” of data is widely considered wrong when simply used to get multiple papers out of one set, but it’s completely unethical when used in this manner.

Still, despite its bad reputation, the IARC doesn’t really appear to be out to simply zap aspartame — by its own “shoot first, ask questions later” standard, at least. It said it found “limited evidence for cancer in humans (for hepatocellular carcinoma, a type of liver cancer).” The italics is not mine, it’s the IARC’s. It added, “Among the available cancer studies in humans, there were only three studies on the consumption of artificially sweetened beverages that allowed an assessment of the association between aspartame and liver cancer.”

“The main animal findings discussed were considered previously by EFSA in 2013 and remain controversial,” Andy Smith, professor in the MRC Toxicology Unit at the University of Cambridge, told Science Media Centre. “As with older studies, more recent human investigations are either negative or show apparent weak associations between cancers and aspartame consumption but IARC admit[s] other factors such as lifestyle, diet and underlying health issues cannot be ruled out.”

Aspartame Doesn’t Cause Cancer

Meanwhile — and this is a big meanwhile — co-released with the IARC study was one from the Joint Food and Agriculture Organization/WHO Expert Committee on Food Additives (JECFA). 

The committee concluded:

There was no convincing evidence from experimental animal or human data that aspartame has adverse effects after ingestion. This conclusion is underpinned by the information that aspartame is fully hydrolyzed in the…