If you rely on Diet Coke to get through the workday, try something new for afternoon joy. You’ve probably been teased for drinking it for a few reasons. (Has it made your teeth black?) But nothing felt like enough reason to stop drinking it…until now. It turns out the sweetener used in it might be cancerous. 

On Thursday, Reuters reported that the World Health Organization’s cancer research arm is preparing to label aspartame as “possibly carcinogenic to humans.” 

The WHO says aspartame could cause cancer. On July 14, the WHO’s cancer research group noted that it was labeling aspartame as a possible carcinogen. The agency’s food safety group said the evidence is limited, and people can still consume a lot of diet soda.

The FDA disagrees, saying aspartame isn’t a possible carcinogen.

Aspartame is one of the most studied food additives. FDA scientists say aspartame is safe when used as approved.

What is aspartame?

Aspartame is a popular low-calorie sweetener that has been around since the 1980s and sold under brand names like Equal. The FDA says it’s 200 times sweeter than sugar, so you only need a little. Some people still use multiple packets in their coffee.

You might not know the name, but you’ve probably used it. It comprises over 6,000 products worldwide, including diet sodas, Snapple teas, and Crystal Light drink mixes. It’s also in many foods, such as gum, candy, breakfast cereals, and sugar-free gelatin like Jell-O. 

Some companies have removed it from their products. Pepsi finally removed it from its drinks in 2020 after years of debate. It now uses an artificial sweetener blend of sucralose and acesulfame potassium to give it that classic cola taste.

Is aspartame safe to eat?

That was until this latest news. The FDA and the American Cancer Society say aspartame is safe. 

Federal health authorities say it’s safe. For example, an adult weighing 150 pounds would have to drink more than 18 cans of zero-sugar soda a day to start experiencing adverse side effects. Studies show that aspartame doesn’t affect blood sugar or insulin levels, even in small amounts. This is why it’s often used in foods for people with diabetes. 

Other studies could be more precise. A 2021 report in the journal Nutrients found that long-term use of aspartame is hard to predict.

What do we know about the WHO’s aspartame declaration?

Reuters says the IARC and JECFA committees kept their findings secret until now. Making them public will be a big step. The last time the WHO studied aspartame was in 1981. It found that the acceptable daily intake was 40 mg per kilogram of body weight. 

These rulings have had a significant impact. They’ve raised concerns among consumers and led to lawsuits. 

Why is there a backlash?

Aspartame has already been criticized for being a cancer hazard. The International Sweeteners Association said the IARC is not a food safety body, and its review of aspartame is not scientific.

The International Council of Beverages Associations also criticized the leaked report, saying it could lead consumers to consume more sugar instead of safer, lower-sugar options. This is the latest setback. Last month, the WHO said people should stop using non-sugar sweeteners because they don’t help with weight control.

But this isn’t just from the food industry. Some pop fans say they’ll keep drinking it, even if it’s unhealthy. “We all die. One Twitter user said, “I’ll drink an ice-cold Diet Coke when I die.”