Since the 1940s, studies have linked the widespread use of artificial sweeteners to cancer in laboratory mice. In the 1970s, this led the United States to put warning labels similar to cigarette packs on anything containing saccharin. But over the past few decades, scientists have dismissed most mouse studies as inconclusive. Rodent research cannot say anything definitive about the risk to humans.
Now a new study, published Thursday in PLOS Medicine, presents disturbing human data.
Researchers looked at more than a decade of health data from 102,865 French volunteers. They found that the consumption of artificial sweeteners was associated with an increased risk of cancer. Specifically, the researchers found that those who consumed any type of artificial sweetener were 13-14% more likely to develop cancer than those who did not.
Researchers individually examined three common sweeteners: aspartame, acesulfame potassium and sucralose.
Cancer rates were 15% higher for the highest users of aspartame and 12% higher for the lowest users. The consumption of aspartame was associated, more than the others, with an increased risk of breast cancer, with a 22% greater chance for the biggest consumers.
Cancer rates were 13% higher for the highest users of acesulfame potassium and 12% for the lowest users.
Sucralose appeared to have the least association with cancer: rates were no higher for the highest consumers and 3% higher for the lowest consumers.
Since artificial sweeteners differ significantly in the amount of each needed to achieve the desired sweetness, the researchers calculated individual high and low measurements for each.
As usual in this type of study, all these figures are the result of adjustments to take into account certain relevant cancer risk factors, such as age, sex and tobacco consumption, in order to make them more representative of the entire French population.
The researchers used data from the NutriNet-Santé study, in which more than 170,000 French citizens agreed to submit information about their health habits and outcomes over decades for researchers to look for correlations. The study began in 2009. The researchers analyzed the data from then until January 2021.
Every six months, volunteers are asked to keep a food diary, recording all the food and drink they consumed that day, including taking photos and saving containers to establish portion sizes. Thanks to this, the researchers got a decent record of artificial sweeteners consumed by an average person per day and in what quantities.
Artificial sweeteners, also known as sugar substitutes, non-nutritive sweeteners, and high-intensity sweeteners, are chemical creations that contain almost no calories, making them seem like a healthy alternative to sugar.
The FDA currently authorizes six artificial sweeteners in the United States, which are widely used in processed foods:
- Saccharin was discovered in 1879 and is still found in fruit juices, candies, jams, jellies, and cookies, especially those labeled “low fat.”
- Aspartame was approved by the FDA in 1981 and is often added to soft drinks, energy drinks, desserts, candy, gum, and weight control products.
- Acesulfame potassium, approved in 1988, is used in soft drinks and protein shakes and is added to drugs to make them more palatable.
- Sucralose was approved in 1998 and is used for the same purposes as aspartame.
- Neotame and advantame, approved in 2002 and 2014 respectively, are not yet used routinely.
The first four are also authorized in the European Union.
Almost as soon as chemists at Johns Hopkins University discovered saccharin, the debate raged over the safety of artificial sweeteners.
Following the passage of the Pure Food and Drug Act in 1906, amid fears of food “tampering”, the newly created Food and Drug Administration considered banning saccharin altogether. President Theodore Roosevelt, who was on a sugar-free diet, stepped in and even called his public health adviser an “idiot” on the matter.
Studies showing that saccharin caused bladder cancer in mice led to its labeling in the United States, a ban in Canada, and a global decline in its use.
Scientists came to believe that this reasoning was flawed, and even that it caused panic; the mechanism by which saccharin caused cancer in mice did not apply to humans, and one had to drink hundreds of twelve-ounce saccharin-infused diet sodas a day to reach the doses given to laboratory mice. The United States removed warning labels in 2000 and Canada reversed its ban in 2011.
After all this, many do not know if they are “better” than sugar.
The researchers say this is the first study to directly evaluate artificial sweeteners and not soft drinks as a substitute. Research like this could settle the artificial sweetener debate, but it will likely reignite it first.
More information: journals.plos.org