For years, artificial sweeteners have been promoted as a healthier alternative to table sugar. But several studies in recent years have suggested that the sweeteners are not necessarily good for your health.
On Thursday, after reviewing the popular artificial sweetener aspartame, the World Health Organization (WHO) found it to be “possibly carcinogenic to humans,” meaning it can cause cancer, while also confirming that the current acceptable daily intake of aspartame — 40 mg per kilogram of body weight per day (about 12 cans of Diet Coke for a 130-pound person) — is still safe to consume. The FDA reportedly disagrees with the WHO’s assessment of the sweetener, but says in a statement that “‘possibly carcinogenic to humans’ does not mean that aspartame is actually linked to cancer.”
Aspartame isn’t the only controversial artificial sweetener. In a May 2023 study published in the Journal of Toxicology and Environmental Health, Part Bresearchers conducted lab experiments on the impact of sucralose (an artificial sweetener marketed as Splenda) and sucralose-6-acetate (a form of sucralose that forms after your body breaks down the sweetener) on human tissue and made several troubling findings .
The researchers found that sucralose-6-acetate is genotoxic, meaning it can damage DNA. The chemical also caused intestinal cells to activate genes related to inflammation and cancer.
The researchers noted that sucralose can damage the cells lining the intestinal wall, leading to leaky gut. Leaky gut syndrome, in case you’re not familiar with it, is a theory that when your gut “leaks,” it releases elements that would normally be removed in the stool into the bloodstream, where they can cause inflammation.
“Overall, the toxicological and pharmacokinetic findings for sucralose-6-acetate raise significant health concerns regarding the safety and regulatory status of sucralose itself,” the researchers wrote.
The study comes shortly after the WHO warned that the use of artificial sweeteners for weight management could potentially contribute to health problems.
Given how popular sucralose and other artificial sweeteners are, it’s understandable to have questions about their safety. Here’s what you need to know.
What does other research say about artificial sweeteners?
There have been some recent studies on artificial sweeteners (also known as non-sugar sweeteners) that suggest that some people should be careful about using them. While the WHO’s recent review calls for more research on aspartame, their May recommendation was based on findings from a systematic review that found that artificial sweeteners have no long-term benefit in reducing body fat in adults or children. But the WHO also noted that the review suggested that long-term use of artificial sweeteners could increase the risk of type 2 diabetes, cardiovascular disease and even death in adults.
A 2022 study of more than 102,000 French adults and their dietary habits found that those who consumed artificial sweeteners, including aspartame, were slightly more likely (1.13 times) to develop cancer after about eight years than those who did not .
Artificial sweeteners have also been linked to some weight gain. A 2020 study published in the Journal of the American Heart Association followed 203 adults who drank at least one sugary drink per day and followed them for a year. One group was given artificially sweetened drinks such as Diet Coke and Diet Pepsi and asked to replace them with their usual soft drinks. Another group received shipments of plain and sparkling water, and a third group was asked to continue their usual pattern of drinking sugary drinks. The researchers found that people who drank artificially sweetened diet drinks gained a pound during the study period, while those who continued to drink sugary drinks gained about 10 pounds and those who drank water and sparkling water lost weight.
A study published in the American Journal of Clinical Nutrition in 2019, compared the effects of sugar and four different low-calorie sweeteners on weight gain in overweight and obese adults, and found that people who drank drinks containing saccharin had “significantly increased body weight” after three months.
A 2018 study published in the journal Molecules found that artificial sweeteners aspartame, sucralose, and saccharin can disrupt gut microbial balance (the balance between good and bad bacteria in your gut).
But the data is mixed. Laboratory studies in rats have linked high doses of saccharin to the development of bladder cancer in rats, but subsequent studies showed that the way saccharin may cause cancer in rats does not apply to humans. As a result, saccharin was originally listed in the US National Toxicology Programs Report on carcinogens as a substance that could reasonably be expected to be a carcinogen – and later deleted.
A 2019 review of 35 observational studies and 21 controlled trials of artificial sweetener use in children and adults, published in BMJ found that there was no evidence that these products affected adults’ eating behavior, mood, or cognition, or their risk of developing cancer, cardiovascular disease, and kidney disease.
Is it safe to use artificial sweeteners?
While the latest research results are concerning, experts say you shouldn’t stress about using artificial sweeteners just yet. “‘Genotoxic’ means that a substance has the potential to damage your DNA,” Jamie Alan, an associate professor of pharmacology and toxicology at Michigan State University, tells Yahoo Life. “Keep in mind that we always receive DNA insults from the environment. It’s the cumulative effect that’s concerning.”
Registered dietitian Scott Keatley, co-owner of Keatley Medical Nutrition Therapy, tells Yahoo Life it’s hard to draw too many conclusions from the latest study. “The real difficulty is saying how these substances will interact with an entire system like the human body and not with cells in a beaker, which this new study has more or less done,” he says.
However, Deborah Cohen, an associa
te professor in the Department of Clinical and Preventive Nutrition Sciences at Rutgers University, tells Yahoo Life that for now “the evidence is compelling,” adding, “I would recommend that people significantly limit their consumption of artificial sweeteners and avoid sugar substitutes. or avoid them altogether.”
She’s concerned about the link between artificial sweeteners and gut problems, something other experts echo. “So many of our body processes take place in the gut, and as our gut microbiome changes, it affects other functions that take place in the body,” writes dietitian Jessica Cording, author of The little book of game changerstells Yahoo Life.
Cording advises her patients to keep the use of artificial sweeteners to a minimum. Among other things, she notes that these products taste incredibly sweet — sucralose, for example, is about 600 times sweeter than table sugar — and says it can make people crave sweet things more than if they hadn’t used artificial sweeteners.
But Colleen Rauchut Tewksbury, a registered dietitian and adjunct associate professor at Penn Medicine, tells Yahoo Life that there’s still a lot we don’t know about how artificial sweeteners affect the body. “For now, the science is too early and not much on humans yet to answer if these are safe and in what amount,” she says. “These types of sweeteners are generally considered safe, so if someone enjoys them and they help meet their health goals, they may be a good option. If someone is specifically concerned about gut health, it may be a good idea to limit use.” non-nutritive sweeteners.”
Keatley agrees, saying you don’t have to avoid artificial sweeteners altogether, but it’s a good idea to watch how much you’re consuming. “Like anything else, these substances should be used in moderation,” he says.
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