Time to Ditch Diet Coke? An Artificial Sweetener in Popular Drinks May Cause Cancer

If you’ve come to rely on your daily Diet Coke to get through the workday (or anything), you might want to consider a new source of afternoon joy. You’ve probably been shamed for drinking it for a few reasons over the years. (Has it really turned anyone’s teeth black?) But nothing felt worthy of abandoning the drink…until now. It turns out, the artificial sweetener used in it — along with thousands of other drinks and foods — might be cancerous.

On Thursday, Reuters reported that the World Health Organization’s cancer research arm, the International Agency for Research on Cancer, (IARC) is preparing to label aspartame as “possibly carcinogenic to humans.” This comes alongside a separate review of the low-calorie sweetener from the Joint WHO and Food and Agriculture Organization’s Expert Committee on Food Additives (JECFA). Both are expected to announce their decisions publicly on July 14.

Naturally, Diet Coke fanatics had some thoughts about the impending announcement. After all, the beverage has almost become a cult favorite, even among celebrities. (Apparently, actor Ben Affleck has a fountain that dispenses Diet Coke and Diet Pepsi in his at-home office).

As we await these findings, here’s what we know so far about the sweetener in question, what health experts are saying, and how people are responding.

Aspartame’s a popular low-calorie artificial sweetener that has been widely used since the 1980s and sold under name brands like Equal. According to the FDA, it’s almost 200 times sweeter than regular granulated sugar, so you should only need a small amount. Regardless, some still require multiple packets in their coffee.

Though the name might not ring any bells, chances are you’ve had it at some point — it’s been used in more than 6,000 products worldwide. This includes everything from zero-sugar beverages and diet sodas to Snapple teas and drink mixes like Crystal Light. It can also be found in beloved foods, such as chewing gum, candy, breakfast cereals, and sugar-free gelatins like Jell-O.

But some companies have made a concerted effort to remove it from their products. After going back and forth on the ingredient for years, Pepsi finally ditched it in 2020 and removed it from its drinks. Now it uses an alternative artificial sweetener that has “a blend of sucralose and acesulfame potassium” to give it that classic cola taste.

Is aspartame safe to consume?
It seemed so, until this latest development. Aspartame has been deemed safe by both the FDA and the American Cancer Society.

According to federal health authorities, it would take a lot for it to be considered bad for your health. For example, an adult weighing 150 pounds would have to drink more than 18 cans of zero-sugar soda a day to start experiencing negative side effects like headaches, seizures, or even depression. Even in small amounts, multiple studies have shown that aspartame doesn’t impact blood sugar or insulin levels, which could explain why it’s often used as a substitute in foods for people with diabetes.

But lingering questions about its safety have prompted extensive research over the years and the findings are all over the map. For example, an observational study in France found that people who consumed larger amounts of artificial sweeteners – including aspartame – had a slightly higher cancer risk. Other studies aren’t as conclusive: A 2021 report published in the peer-reviewed journal Nutrients, found that “the results of its long-term use remain difficult to predict.”

What do we know about the WHO’s aspartame declaration?
According to Reuters, both the IARC and JECFA committees’ findings were kept under wraps until now, and the process of making them public will be no small step. The last time the WHO studied aspartame was in 1981, when it determined that the acceptable daily intake for the additive was 40 mg per kilogram — or 2.2 lbs — of body weight.

What’s more, these kinds of rulings have had a massive impact — on top of raising concerns among consumers, they’ve also led to lawsuits. In 2015, the IARC concluded that glyphosate, which is often used to kill weeds, is “probably carcinogenic.” Then in 2021, even after these findings had been questioned by the European Food Safety Authority, the Supreme Court upheld a verdict that found Bayer responsible for a couple’s cancer after using Bayer’s Roundup weed killer.

Along with influence has come some valid criticism. Some argue that the IARC’s assessments can be confusing to the public. The agency essentially has four different levels of classification: Carcinogenic, probably carcinogenic, possibly carcinogenic, and not classifiable. But counter to what you might assume, these levels are based on the strength of the evidence, rather than how dangerous a substance is. As Reuters notes, the hope is that listing aspartame as a possible carcinogen will spark more research.

Why is there backlash?
Unsurprisingly, word of Aspartame’s potential cancer hazard has already prompted criticism. The International Sweeteners Association questioned the IARC’s legitimacy ahead of its upcoming ruling, saying the agency is “not a food safety body and their review of aspartame is not scientifically comprehensive.”

Meanwhile, the International Council of Beverages Associations also condemned the leaked report, warning that it “could needlessly mislead consumers into consuming more sugar rather than choosing safe no- and low-sugar options.” This just marks the latest blow: Last month, the WHO advised consumers to stop using non-sugar sweeteners, saying that they didn’t help for with weight control.

But this pushback isn’t just coming from the food industry. Some pop aficionados have declared they’ll continue drinking it, even if there are health risks. “We all die. And I’ll go out with an ice-cold Diet Coke when that day comes,” one Twitter user declared.