Tackling the Aspartame Argument with a UConn Health Expert

Natalie Ranelli, registered dietitian in UConn Health’s Neag Comprehensive Cancer Center, weighs in on synthetic sweetener’s safety

A notepad showing the chemical diagram of the artificial sweetener aspartame next to a bowl of it.

(Adobe Stock)

While two groups within the World Health Organization are in disagreement over how safe aspartame is for human consumption, a UConn Health dietitian says it has its place in a well-balanced approach to a healthy lifestyle when taken in moderation.

Last week the WHO’s International Agency on Cancer Research reclassified aspartame into Group 2B, “possibly carcinogenic to humans.” Then WHO and the United Nations’ Food and Agriculture Organization Joint Expert Committee on Food Additives reiterated its previous position that the acceptable daily intake of aspartame translates to the equivalent of a person weight 150 pounds drinking about a dozen cans of diet soda a day.

The concurrent announcements added to the debate over chemical sweeteners that goes back decades.

Natalie Ranelli portrait
Natalie Ranelli is a registered dietitian who works with patients in the Carole and Ray Neag Comprehensive Cancer Center at UConn Health. (Tina Encarnacion/UConn Health)

So where does that leave diet soda drinkers, sugar-free gum chewers, and the like?

“Despite all the conflicting studies and guidance, this new announcement would not be reason to panic or immediately throw out your diet soda,” says Natalie Ranelli, a registered dietitian who works with patients in UConn Health’s Carole and Ray Neag Comprehensive Cancer Center. “I’d compare it to the sun. The sun may cause skin cancer, but if you are not exposed to it as much, your risk is lower.”

There’s also the notion that there are several other dietary threats to our health, and our energy is better spent on limiting our intake things like saturated fat, processed foods, sodium, and alcohol.

“Aspartame is a much smaller portion of a person’s diet, while sugar, fat, sodium, and alcohol, etc., tend to make up larger portions of the diet and can have potentially more negative health outcomes,” Ranelli says. “There is research showing stronger associations with some of those factors and cancer or other comorbid conditions overall.”

The IARC’s 2B classification generally applies when there is either limited, but not convincing, evidence for cancer in humans, or convincing evidence for cancer in experimental animals, according to the WHO. Those on both sides of the debate agree more study is needed.

Ranelli points out that the 2B category also includes things like aloe vera, pickled vegetables, and nickel.

Her takeaway is, when it comes to weighing the risks of sugar and artificial sweeteners, it doesn’t always have to be one or the other.

“It definitely is a common yet difficult dilemma,” Ranelli says. “I believe everything can be part of a balanced, healthy diet — ‘balanced’ being key. ‘Diet’ foods using artificial sweeteners can definitely be beneficial for diabetics or individuals tracking calories. I think portion control of both these foods is the best practice; sometimes having less of the ‘real’ thing can be more satisfying than eating a large portion of ‘diet’ food. So it’s just about finding the right balance for the individual.”


Learn more about nutrition services in the Carole and Ray Neag Comprehensive Cancer Center.