Diet Soda May Be Linked to Stroke, Dementia


People pivoting to diet soda as a healthier alternative to sweetened beverages may want to exert caution — a new study found that diet beverages are linked to an increased risk of stroke and dementia.

The study, appearing in the journal Stroke, assessed the long-term health outcomes of about 4,400 people over the age of 45. The researchers monitored health patterns for more than a decade and controlled for other leading causes of stroke and dementia, including age, sex, education, physical activity and other factors.

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After adjusting for the genetic and lifestyle factors, they discovered a striking correlation — those who consumed artificially sweetened beverages on a daily basis were about three times as likely to experience a stroke or develop dementia compared to people who consumed diet drinks less frequently.

However, the researchers are quick to point out that their findings don’t identify a smoking gun; instead, the link between artificially sweetened beverages and stroke and dementia, while present, remains a gray area.

“Our study shows a need to put more research into this area given how often people drink artificially-sweetened beverages,” said Dr. Matthew Pase, a Senior Fellow in the department of Neurology at Boston University School of Medicine.

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The new study arrives amid other research that ties diet soda to a heightened risk of diabetes and an uphill battle to lose weight.

In the current study, the clinical findings are associated with difficult, sometimes fatal, health challenges. The diet-soda ties “included a higher risk of ischemic stroke, where blood vessels in the brain become obstructed and Alzheimer’s disease dementia, the most common form of dementia,” noted Pase.

Sugary Drinks Not Excepted

While the study in Stroke didn’t find a direct link between regular soda and the risk of stroke or dementia, the research turned up other cognitive-related health implications.

“Our findings indicate an association between higher sugary beverage intake and brain atrophy, including lower brain volume and poorer memory,” said Pase.

Fewer people reported drinking regular sodas than diet sodas, which may be a reason for the lack of association between the sugary drinks and cognitive challenges, noted the researchers. Other research has tied sugary-drink consumption to cardiometabolic risk factors, such as high blood pressure, that are the leading cause of dementia and stroke.

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Because the current study is observational in nature, the exact causation of stroke and dementia is inconclusive, but the researchers call for additional exploration into this significant public health topic.

In a related release, an expert from the American Heart Association (AHA) weighed in with some words of caution for both regular and diet soda drinkers.

“We know that limiting added sugars is an important strategy to support good nutrition and healthy body weights, and until we know more, people should use artificially sweetened drinks cautiously. They may have a role for people with diabetes and in weight loss, but we encourage people to drink water, low-fat milk or other beverages without added sweeteners,” said Dr. Rachel K. Johnson, past Chair of the AHA’s Nutrition Committee.