Common sweetener in sugar-free drinks linked to serious heart problems

Aspartame has long been marketed as a guilt-free alternative to sugar in popular food products, ranging from zero-calorie Diet Coke to sugar-free Jell-O. It's also had a pretty bad rap, and the artificial sweetener has now been linked to an increased risk of heart attacks and stroke in mice. But not everyone's convinced this is as bad as it sounds for humans.

That's from a study published in Cell Metabolism, authored by cardiovascular health experts and clinicians in China, Sweden, and the US. Their work suggests that aspartame consumption may have negative impacts on vascular health.

For 12 weeks, the researchers fed mice daily doses of food containing the same quantity of aspartame as you'd find in three cans of diet soda. These mice developed larger and more fatty plaques in their arteries compared to mice whose diets did not include the sweetener. The experimental group also exhibited higher levels of inflammation, which is associated with cardiovascular disease.

More precisely, they found aspartame can trigger an increase in insulin levels, which in turn contributes to atherosclerosis, a condition characterized by the buildup of fatty plaques in the arteries.

It's worth noting that aspartame has previously been linked to cardiovascular disease – as well as cancer, impaired memory, and anxiety-like conditions – but this new research has identified the mechanism that's to blame. An immune signal called CX3CL1 that becomes highly active under insulin stimulation. CX3CL1 acts like a bait, catching immune cells that pass by, which then stoke blood vessel inflammation and cause heart issues.

Should you therefore be worried about your Diet Coke habit? Not so fast, says an expert who wasn't related to this study.

Dr. Ian Musgrave, a senior lecturer within the Discipline of Pharmacology at the University of Adelaide, is of the opinion this study's findings may not be directly relevant to humans.

"This study was done in mice that were genetically engineered to lack a key lipid transporter, then fed a high-fat diet to stimulate the formation of fatty plaques in their blood vessels," he said. "While these experiments are elegant, the relevance of these experiments to humans is unclear. Genetically engineered mice on a diet specifically designed to accelerate plaque formation is unlikely to replicate the biology and dietary situation of most humans.

"Importantly, in the blood vessel experiments, the effects of an equivalently sweet dose of sugar was not studied, nor the effect of the reduction in calorie intake by the amount of aspartame consumed. While the study may have given us a new target for treating plaque build-up in one of the body's inflammatory molecules, it does not suggest people should give up their artificially sweetened drinks."

Others, like senior lecturer Dr. Yutang Wang from Federation University Australia and Professor Mark L Wahlqvist AO, Head of Medicine at Monash University and Monash Medical Centre, believe this is yet another critical warning against the potential harmful effects of artificial sweeteners.

Dr. Wang noted that "... it adds weight to the growing body of research urging caution. It may be time to reconsider our consumption of artificially sweetened products. Reducing their intake could be a simple yet powerful step to protect ourselves from heart attacks and strokes."

That's a sentiment shared by the researchers. "Artificial sweeteners have penetrated almost all kinds of food, so we have to know the long-term health impact,” said Yihao Cao from Karolinska Institute, and an author of the paper. To that end, the team intends to verify its findings in humans.

There's also a silver lining here: the researchers found that when they eliminated the receptors for the CX3CL1 immune signal in the mice they experimented on, they found that plaque didn't build up and clog their arteries. That could prove to be an avenue for treating chronic conditions that stem from blood vessel inflammation, such as stroke, arthritis, and diabetes.

Source: Scimex/NewAtlas