Consuming artificial sweeteners may increase the risk of developing diabetes, according to a new study.
In work that raises questions over whether artificial sweeteners – widely seen as “healthier” than sugars – should be reassessed, the researchers said the substances altered the balance of microbes in the gut linked to susceptibility to metabolic diseases like diabetes.
“In our studies we found that artificial sweeteners may drive, or contribute to… an exaggerated elevation in blood glucose levels – the very same condition that we often aim to prevent by consuming them,” said Eran Elinav of the Weizmann Institute of Science in Israel, who co-led the work.
Researchers conducted a series of experiments in both mice and humans, repeating them several times to check their results. They used three common artificial sweeteners – saccharin, sucralose, and aspartame.
They found that mice whose drinking water was supplemented with glucose and a sweetener developed marked glucose intolerance compared with mice drinking water alone, or water with just sugar in it. The artificial sweeteners exert this effect by altering the balance of gut microbes, they said.
Then the researchers analyzed around 400 people and found that the gut bacteria in those who consumed artificial sweeteners was significantly different from those who did not. They also found non-caloric artificial sweeteners (NAS) eaters had “markers” for diabetes, including raised blood sugar levels and glucose intolerance.
The scientists then put seven lean and healthy volunteers who did not normally consume artificial sweeteners on controlled 7-day diet of high NAS intake. Those results were interesting: four became glucose intolerant, and their gut microbiomes shifted towards a balance already known to be associated with susceptibility to metabolic diseases. The other three seemed to be resistant to saccharin’s effects.
“This underlines the importance of personalized nutrition — not everyone is the same,” says Elinav.
Yanina Pepino of Washington University in St. Louis did not participate in the study, but she said the results make a convincing case that sweeteners hamper the body’s handling of sugar by altering gut bacteria. And it adds to her belief that sweeteners and sugar should be used in moderation, especially by children, she said.
“It’s really providing strong data suggesting we need to do more research,” she said.
Elinav’s research team wrote the following in their study:
“These results indicate that non-caloric artificial sweeteners may exacerbate, rather than prevent, metabolic disorders such as glucose intolerance and diabetes.”
Smaller studies have also shown an association between the use of artificial sweeteners and the occurrence of metabolic disorders. But, this is the first research that suggests that sweeteners might be exacerbating metabolic disease, and that this might happen through the gut microbiome, the diverse community of bacteria in the human intestines.
It appears that artificial sweeteners are causing or exacerbating the very things they were created to prevent or reduce.