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A new study finds a common sweetener may damage your DNA. Getty Images
  • A new study finds that a common artificial sweetener may damage your DNA.
  • The zero-calorie sweetener in question is sucralose, sold under the brand name Splenda. It is about 600 times sweeter than table sugar.
  • The study found that sucralose may lead to a leaky gut lining, and increase the activity of genes related to inflammation and cancer.

A study from researchers at North Carolina State University suggests that a chemical formed from one artificial sweeteners might also damage our DNA.

The zero-calorie sweetener in question is sucralose, which is about 600 times sweeter than table sugar,

The World Health Organization (WHO) recently recommended against using certain sugar substitutes to help lose weight, saying there is little evidence of long-term benefit.

Sucralose, known in the United States by the brand name Splenda, is used in thousands of products, including baked goods, beverages, chewing gum, gelatins and frozen dairy desserts.

In addition to DNA damage, the new study found that sucralose may lead to a leaky gut lining, and increase the activity of genes related to inflammation and cancer.

The findings from this study “raise health and safety concerns regarding the continued presence of sucralose in the food supply,” the authors wrote May 29 in a paper published in the Journal of Toxicology and Environmental Health, Part B.

Regulatory approval of sucralose is based on studies that assume that it passes through the body unchanged.

But the authors of the new study point to earlier research showing that certain gut bacteria can transform sucralose into a similar molecule called sucralose-6-acetate.

This compound is also found in small amounts in some commercial sucralose products, they added, a byproduct of the manufacturing process.

A spokesperson for Splenda, one of the most frequently marketed forms of sucralose in the United States, said “we rigorously and routinely test and monitor for any impurities in our products … We can confirm that sucralose-6-acetate is not present in Splenda Brand sucralose.”

The researchers did not test Splenda sucralose products in their study, the company spokesperson confirmed.

In the new study, when researchers exposed human blood cells to sucralose-6-acetate, they found that it caused breaks in DNA. This could potentially increase the risk of cancer or other health problems.

Regulatory agencies such as the European Food Safety Authority set maximum levels of sucralose-6-acetate allowed in food products.

However, the amount of this chemical in a single serving of a sucralose-containing beverage could be high enough to potentially damage DNA, the authors of the new study pointed out.

People may also be exposed to even higher levels when gut bacteria convert sucralose into sucralose-6-acetate, they said.

Additional lab-based experiments carried out by the researchers raised other concerns about the potential impact of this chemical on the body.

In one test, researchers exposed human intestinal tissue to sucralose-6-acetate, finding that it increased the activation of genes associated with inflammation, oxidative stress, and cancer.

They also found that sucralose-6-acetate — and sucralose itself — damaged the junctions that hold together the cells that line the human intestines, causing the gut to become leaky.

This might allow gut microbes and molecules to move from the gut into the body, including ones that would normally pass out of the body in the feces.

A leaky gut is associated with inflammatory bowel disease (IBD) and may contribute to chronic liver disease.

In response to the new study, a spokesperson for the International Sweetener Association emphasized that the safety of sucralose has been confirmed by global food safety and regulatory bodies, including the Food and Drug Administration and the European Food Safety Authority.

“Sucralose has undergone one of the most extensive and thorough testing programs conducted on any food additive in history, resulting in consensus on its safety throughout the global scientific and regulatory community,” they said.

In addition, they said levels of sucralose-6-acetate in sucralose products are “tightly controlled by robust manufacturing processes.”

Testing done during manufacturing, though, would not account for sucralose-6-acetate created by gut bacteria from sucralose.

While laboratory testing does not always translate into actual harms in people — which is dependent on how much people consume and other factors — it points out potential risks from ingested chemicals.

Given the results of the new study and other recent research, the authors of the paper called for a new regulatory review of the health effects of sucralose in food products.

Kate Cohen, a registered dietitian at the Ellison Clinic, part of the Ellison Institute for Transformative Medicine and Providence Saint John’s Health Center, in Los Angeles, Calif., said the new study raises another red flag about the potential health risks of certain artificial sweeteners.

This includes sucralose.

In a study published in 2022 in The BMJ, a group of French researchers found that consumption of sucralose was linked to a higher risk of cardiovascular disease, stroke and coronary heart disease.

Other sugar substitutes, such as aspartame and acesulfame potassium, also increased the risk of these outcomes, researchers found.

Another 2022 study, published in the journal Cell, showed that sucralose — and saccharin — could potentially elevate blood sugar levels. This is linked to a higher risk of type 2 diabetes (T2D), heart disease and stroke.

In this study, these sugar substitutes “not only caused blood sugar to rise like [table] sugar,” said Cohen, “but they also caused changes in the microbiome — meaning they didn’t go through the body with no effect as was previously believed.”

The gut microbiome is a collection of bacteria and other microbes living in the intestines. Disruptions in the microbiome may contribute to obesity, type 2 diabetes, inflammatory bowel disease (IBD), and certain types of cancer.

A healthy gut microbiome also supports the immune system, and heart and brain health.

“Some studies suggest that [certain artificial sweeteners] may have a negative impact on our microbiome, which could lead to poorer immune and metabolic function and mental health,” said Megan Hilbert, a registered dietitian with Top Nutrition Coaching.

Research in mice has found that a low dose of sucralose can alter the animals’ gut microbiome.

Another study in people found a similar impact of sucralose on the levels of certain intestinal bacteria. This study also showed that sucralose negatively affected blood concentrations of glucose and insulin.

Cohen said when people eat foods with sugar substitutes, they replace the health risks of added sugars with a whole new list of risks, “many of which we don’t know about yet, because [artificial sweeteners] haven’t all been studied to the level they need to be.”

In addition, even though non-sugar sweeteners have zero or few calories, they don’t reduce the craving for sweetness.

As a result, “they may have the reverse effect of making someone believe they can eat unlimited amounts of snacks or treats because they are ‘sugar-free,’” said Cohen.

Foods can impact health directly through the effects they have on the body. But certain foods can also impair health by shifting the overall diet quality.

When people fill up on processed snacks — whether made with table sugar or a sugar substitute — they may eat fewer nutrient-dense foods such as fruits, vegetables, nuts and seeds. These foods are important for physical and mental health.

To support overall health, Cohen recommends that people use artificial sweeteners in moderation, if at all.

Hilbert agrees: As with sugar, “small amounts [of sugar substitutes] are fine, but in excess they may negatively impact other areas of the body,” she said. “Ultimately, they shouldn’t be treated as something to consume limitlessly just to get a sweet fix.”

If you do want something sweet without sugar, Cohen suggests using stevia or monk fruit sweeteners. Some of these products, though, contain the artificial sweetener erythritol, which has been linked to a higher risk of heart attack and stroke.

Erythritol and other sugar alcohols such as mannitol and xylitol can also cause excess gas and bloating in people with sensitive intestines, said Hilbert.

So look for products that don’t contain erythritol. Another option is to use fresh leaves from the stevia plant, which, like other herbs, can be grown in your backyard garden or even in your home.

Over time, though, she suggests shifting your diet away from overly sweet foods, which may make other foods — like fresh vegetables — taste much better.

“Start cutting your sweeteners in half for a few weeks and gradually reduce from there,” said Cohen. “Your taste buds will adjust and you’ll be much healthier.”