Artificial Sweeteners Linked to Higher Cardiovascular Event Risk

-Sue Hughes

Health concerns about the consumption of artificial sweeteners could be strengthened with the publication of a new study linking their intake to increased risk of heart disease and stroke events.

In this latest large-scale, prospective study of French adults, total artificial sweetener intake from all sources was associated with increased risk overall of cardiovascular and cerebrovascular disease.

The study was published online in the BMJ on September 7.

The current study differs from those done previously in that it includes artificial sweetener intake from both food and drinks, whereas previous studies have focused mainly on artificial sweetener content of beverages alone.

“Here we have quantified for the first time the global exposure to artificial sweeteners. This is not just beverages but includes the use of tabletop sweeteners, and other foods that include artificial sweeteners such as yogurts and desserts. This is the first time this information has been correlated to risk of heart disease,” senior author Mathilde Touvier, MD, Sorbonne Paris Nord University, France, told theheart.org | Medscape Cardiology.

Just over half of the artificial sweetener intake in the study came from drinks, with the rest coming from tabletop sweeteners and foods.

“We included hard cardio- and cerebrovascular clinical endpoints such as a heart attack or stroke, and our results suggest that the amount of artificial sweetener in less than one can of soda could increase the risk of such events,” Touvier noted.

“This is an important and statistically significant association which shows robustness in all models after adjusting for many other possible confounding factors,” she said.

“There is now mounting evidence correlating artificial sweeteners to weight gain and heart disease,” she concluded. “My advice would be that we all need to try to limit sugar intake, but we should not consider artificial sweeteners as safe alternatives. Rather, we need to try to reduce our need for a sugary taste in our diet.”

But another leading researcher in the field urges caution in interpreting these results.

John Sievenpiper, MD, Departments of Nutritional Sciences and Medicine, University of Toronto, Canada, commented to theheart.org | Medscape Cardiology: “This paper shows the same relationship seen by many other large prospective cohorts which model the intake of artificial sweeteners as baseline or prevalent exposures.

“These observations are well recognized to be at high risk of residual confounding from behavior clustering and reverse causality in which being at risk for cardiovascular disease causes people to consume artificial sweeteners as a strategy to mitigate this risk as opposed to the other way around.”

Risk Increased by 9%

The current study included 103,388 French adults from the NutriNet-Sante cohort, of whom 37.1% reported consumption of artificial sweeteners. The sweeteners assessed were mainly aspartame (58% of sweetener intake), acesulfame potassium (29%), and sucralose (10%), with the other 3% made up of various other sweeteners including cyclamates and saccharin.

Results showed that over an average 9 years follow up, artificial sweetener intake was associated with a 9% increased risk of cardiovascular or cerebrovascular events, including myocardial infarction, acute coronary syndrome, angioplasty, angina, stroke, or transient ischemic attack, with a hazard ratio of 1.09 (95% CI, 1.01 to 1.18; P = .03).

The average intake of artificial sweeteners among those who reported consuming them was 42.46 mg/day, which corresponds to approximately one individual packet of tabletop sweetener or 100 mL of diet soda.

“We don’t have enough evidence to work out an amount of artificial sweetener that is harmful, but we did show a dose-effect association, with a higher risk of cardiovascular events with higher consumption,” Touvier said.

“Higher consumption in this study was a mean of 77 mg/day artificial sweetener, which is about 200 mL of soda — just a bit less than one standard can of soda,” she added.

The absolute incidence rate of cardiovascular or cerebrovascular events in higher consumers was 346 per 100,000 person years vs 314 per 100,000 person years in nonconsumers.

Further analysis suggested that aspartame intake was particularly associated with increased risk of cerebrovascular events, while acesulfame potassium and sucralose were associated with increased coronary heart disease risk.

Study Strengths

Touvier acknowledged that dietary studies, which generally rely on individuals self-reporting food and drink intake, are always hard to interpret. But she said this study used a more reliable method of dietary assessment, with repeated 24-hour dietary records, which were validated by interviews with a trained dietitian and against blood and urinary biomarkers.

And while residual confounding cannot be totally excluded, she pointed out that models were adjusted for a wide range of potential sociodemographic, anthropometric, dietary, and lifestyle confounders.

Touvier also noted that cases of cardiovascular disease in the first 2 years of follow up were excluded to minimize the bias caused by individuals who maybe have switched to artificial sweeteners because of a cardiovascular issue.

“While this study has many strengths, it cannot on its own prove a causal relationship between artificial sweetener and increased cardiovascular risk,” she added. “We need health agencies to examine all the literature in the field. This is however another important piece of evidence.”

Touvier says that although observational studies have their issues, they will form the basis of the evidence on the effects of artificial sweeteners on health.

“Randomized studies in this area can only really look at short-term outcomes such as weight gain or biomarker changes. So, we will have to use observational studies together with experimental research to build the evidence. This is what happened with cigarette smoking and lung cancer. That link was not established by randomized trials, but by the accumulation of observational and experimental data.”

Different Artificial Sweeteners May Be Better?

Commenting on the study for theheart.org | Medscape Cardiology, Kim Williams Sr, MD, University of Louisville, Kentucky, pointed out that this study included artificial sweeteners that increase insulin or decrease insulin sensitivity, and that insulin spikes increase obesity, insulin resistance, hypertension, and atherosclerosis.

“There are some safer artificial sweeteners, that do not increase insulin much or at all, such as erythritol, yacon root/yacon syrup, stevia root, but they weren’t included in the analysis,” Williams added.

Also commenting for theheart.org | Medscape Cardiology, Sievenpiper explained that most studies on artificial sweeteners look at their consumption in isolation without considering how they compare to the intake of the sugars that they are intended to replace.

“The comparator matters as no food is consumed in a vacuum,” he said.

To address this, Sievenpiper and colleagues have recently published a systematic review and meta-analysis of the prospective cohort study evidence that shows if exposure to artificial-sweetened beverages is modeled in substitution for sugar-sweetened beverages then they are associated with less coronary heart disease, cardiovascular mortality, and all-cause mortality.

On the other hand, if exposure to artificial-sweetened beverages is compared with water, then no difference in these outcomes was seen.

“These observations are more biologically plausible, robust, and reproducible and agree with the evidence for the effect of artificial sweeteners on intermediate risk factors in randomized trials,” Sievenpiper notes.

His group has also recently published a review of randomized studies showing that when compared with sugar-sweetened beverages, intake of artificial-sweetened beverages was associated with small improvements in body weight and cardiometabolic risk factors without evidence of harm.

“I think the context provided by these studies is important, and taken together, the totality of the evidence suggests that artificial sweeteners are likely to be a useful tool in sugar reduction strategies,” Sievenpiper concludes.

The current study was funded by the European Research Council (ERC) under the European Union’s Horizon 2020 research and innovation program, French National Cancer Institute, French Ministry of Health, IdEx Université de Paris Cité, Bettencourt-Schueller Foundation Research Prize 2021. The authors have disclosed no relevant financial relationships.