Artificial sweeteners and cancer risk: what a decade of French data actually shows

TL;DR: Most people swap sugar for artificial sweeteners to avoid disease, but the evidence is not exactly clean. A French study of over 100,000 volunteers across more than a decade found that artificial sweeteners and cancer risk are linked, with consumers showing 13 to 14 percent higher odds. Aspartame led the pack at 22 percent for breast cancer. Sucralose had the weakest link.

When we talk about health and diet, most people know that controlling the ingestion of sugar is essential to maintain weight and avoid diseases. So when seeking a healthier diet without too many excesses, most people turn to artificial sweeteners. And then come the doubts: are sweeteners safe? Can they cause cancer?

Since 1940, studies link the use of artificial sweeteners with cancer in lab mice. In the 70s, this led the US to put warning labels on anything containing saccharine, similar to cigarette packages. Here is what the newer human research shows.

What did the French study actually measure?

Researchers analyzed more than a decade’s worth of health data from 102,865 French volunteers. The study started in 2009, and the researchers analyzed data from that year until January 2021. Every six months, the volunteers were asked to keep a dietary diary. They write down everything they eat and drink during the day and even take pictures and save labels for determining portion sizes.

Thanks to these annotations, the researchers had a decent register of which and how many artificial sweeteners one would consume in an average day.

What did the data show about artificial sweeteners and cancer?

They found out that the consumption of artificial sweeteners was associated with an increased risk of cancer. More specifically, researchers found that people who consumed any kind of artificial sweeteners had a 13 to 14 percent higher chance of developing cancer than those who didn’t. Researchers analyzed three common sweeteners: aspartame, acesulfame potassium, and sucralose.

The cancer rates were 15 percent higher for frequent consumers of aspartame and 12 percent for those who rarely consumed it. Aspartame was more associated with an increased risk of breast cancer than the other sweeteners, with a 22 percent higher chance for frequent consumers. Cancer rates were 13 percent for frequent consumers of acesulfame potassium and 12 percent for those who rarely consume it. Sucralose seemed to have the lowest association with cancer: the rates were only 4 percent for frequent consumer and 3 percent for those who rarely consumed it.

Which sweeteners are allowed in the US today?

Nowadays, the FDA allows six artificial sweeteners in the US, which are widely used in industrialized foods. Saccharine was found in 1879 and can be found in fruit juices, sweets, jams, and cookies, especially those with “low-fat” labels. Aspartame was approved by the FDA in 1981 and is frequently added to sodas, energy drinks, desserts, sweets, gums, and products for weight control.

Acesulfame potassium, approved in 1988, is used in sodas and protein shakes and can be added to medication to make them more palatable. Sucralose was approved in 1998 and is used for most of the same things as aspartame. Neotame and advantame, approved in 2002 and 2014 respectively, are not as common yet. The first four are allowed by the European Union too.

The takeaway

The evidence on artificial sweeteners and cancer risk is not a smoking gun, but a decade of data from more than a hundred thousand French adults is hard to shrug off. Frequent aspartame use carried the biggest jump, especially for breast cancer. Sucralose sat at the low end. If you want more pieces like this in your inbox, the newsletter is the place.

Frequently asked questions

How many people were in the French sweetener study?

Researchers analyzed more than a decade’s worth of health data from 102,865 French volunteers. The study started in 2009, and the researchers analyzed data from that year until January 2021.

How much did artificial sweeteners raise cancer risk overall?

Researchers found that people who consumed any kind of artificial sweeteners had a 13 to 14 percent higher chance of developing cancer than those who didn’t.

Which sweetener had the strongest cancer link?

Aspartame was more associated with an increased risk of breast cancer than the other sweeteners, with a 22 percent higher chance for frequent consumers. Overall, the cancer rates were 15 percent higher for frequent consumers of aspartame and 12 percent for those who rarely consumed it.

Which sweetener had the weakest cancer link?

Sucralose seemed to have the lowest association with cancer: the rates were only 4 percent for frequent consumer and 3 percent for those who rarely consumed it.

How many artificial sweeteners does the FDA allow?

Nowadays, the FDA allows six artificial sweeteners in the US, which are widely used in industrialized foods: saccharine, aspartame, acesulfame potassium, sucralose, neotame, and advantame.