- A controversial study ties diet sodas to a higher risk of stroke and dementia
- One expert called the new study “a piece of a larger puzzle”
The study sheds light only on an association, as the researchers were unable to determine an actual cause-and-effect relationship between sipping artificially sweetened drinks and an increased risk for stroke and dementia. Therefore, some experts caution that the findings should be interpreted carefully.
No connection was found between those health risks and other sugary beverages, such as sugar-sweetened sodas, fruit juice and fruit drinks.
“We have little data on the health effects of diet drinks and this is problematic because diet drinks are popular amongst the general population,” said Matthew Pase, a senior research fellow in the department of neurology at Boston University School of Medicine and lead author of the new study.
“More research is needed to study the health effects of diet drinks so that consumers can make informed choices concerning their health,” he said.
In the older-than-45 group, the researchers measured for stroke and in the older-than-60 group, they measured for dementia.
“The sample sizes are different because we studied people of different ages,” Pase said. “Dementia is rare in people under the age of 60 and so we focused only on those aged over 60 years for dementia. Similarly, stroke is rare in people aged under 45 and so we focused on people older than age 45 for stroke.”
The researchers analyzed how many sugary beverages and artificially sweetened soft drinks each person in the two different age groups drank, at different time points, between 1991 and 2001. Then, they compared that with how many people suffered stroke or dementia over the next 10 years.
Compared to never drinking artificially sweetened soft drinks, those who drank one a day were almost three times as likely to have an ischemic stroke, caused by blocked blood vessels, the researchers found.
They also found that those who drank one a day were nearly three times as likely to be diagnosed with dementia.
Those who drank one to six artificially sweetened beverages a week were 2.6 times as likely to experience an ischemic stroke but were no more likely to develop dementia, Pase said.
“So, it was not surprising to see that diet soda intake was associated with stroke and dementia. I was surprised that sugary beverage intake was not associated with either the risks of stroke or dementia because sugary beverages are known to be unhealthy,” Pase said.