Aspartame is an artificial chemical sweetener widely used in various food and beverage products such as diet drinks, chewing gum and ice cream, from the 1980s onwards – Copyright GETTY IMAGES NORTH AMERICA/AFP/File MARIO TAMA

The scientific and medical debate about the possible link between Cancer and aspartame—sweetener of many fizzy drinks and thousands of other foods—continues. Resolving the complex data has not been resolved with the World Health Organization’s decision to classify the artificial sweetener as possibly carcinogenic while also maintaining the current recommendation of safe daily intake.

Aspartame is not naturally occurring and has to be manufactured. It is made of a modified version of phenylalanine and aspartic acid linked together; these are both amino acids that form the building blocks for proteins in humans and other animals.

The contradictory decision was based on somewhat conflicting rulings from two WHO committees, the International Agency for Research on Cancer (IARC) and the Joint FAO/WHO Expert Committee on Food Additives (JECFA).

On one hand, IARC’s 25 international experts evaluated research and found an increased risk of cancers but not enough consistent Evidence pointed to moving aspartame to WHO’s highest risk category for carcinogens. The committee designated aspartame as possibly carcinogenic, a category that includes an array of products consumed regularly.

JECFA, on the other hand, deemed evidence too inconclusive to change the daily recommended intake of aspartame and said current daily intake of 40 milligrams per kilogram of body weight, or between 9 and 14 cans of diet soft drink per day for someone weighing 150 pounds, was still considered safe.

To make matters more complicated, the U.S. Food and Drug Administration (FDA) took a position and stated it disagreed with the IARC’s carcinogen classification and backed the JECFA’s daily intake status quo.

Where does all this leave the consumer? Jackie Goodrich is a toxicologist and research associate professor of environmental health sciences at U-M’s School of Public Health has explained whether consumers should be concerned.

Goodrich explains to Digital Journal: “Consumers should be aware that this designation means the evidence across different types of studies is not enough to link aspartame to cancer with confidence. There has been evidence in certain studies linking aspartame to cancer, but there is inconsistency when looking across all studies.”

There are also limitations that do not allow scientists to directly link aspartame to cancer. Here Goodrich adds: “Other things that we call confounders might explain the link, and scientists have work to do to figure out the true cause and effect relationship. In the meantime, we already know that consuming high amounts of sugar is not good for health. Thus, consumers should take a metered approach and find ways to reduce their overall consumption of sugar and artificial sweeteners without necessarily cutting one particular sweetener fully out of their diets.”

Looking at the science, Goodrich assesses: “Over the years, fairly convincing studies in both rats and humans have linked aspartame or artificial sweeteners in general to several cancers. These studies raise concern about aspartame and, in some cases, other sweeteners. However, the evidence has been inconsistent with other studies showing no association with cancer. The process by IARC systematically reviews all evidence, weighted by the strengths and limitations of each study design, instead of being driven by one study alone.”

In terms of “would you drink or eat aspartame?”, Goodrich answers: “As a toxicologist, I recognize that reducing harmful (or potentially harmful) exposures whenever I can, is beneficial. As a public health professional, I also know that heavy consumption of sugar sweetened beverages is not a healthy choice. I limit my consumption of both sugar sweetened and artificially sweetened beverages and products like yogurt but do not avoid them completely. Whenever I can, I seek out alternatives like naturally low sugar yogurt, unsweetened teas, etc.”

She adds: “I also consume products with natural sweeteners like Stevia, but try to avoid becoming dependent on one particular sweetener. As science advances, sometimes we find evidence we do not expect about our favourite products.”