Researchers also found that people who drank diet soda daily were nearly three times as likely to develop stroke and dementia when compared to those who did not consume diet soda. Among that "high intake" group, they found multiple signs of accelerated brain aging, including smaller overall brain volume, poorer episodic memory, and a shrunken hippocampus, all risk factors for early-stage Alzheimer's disease.
Led by researchers at Boston University School of Medicine, the authors of the Stroke study conducted a review of data collected through the Framingham Heart Study, a multi-decade observational review that began with more than 5,000 volunteer participants in 1948 and has included their offspring since 1971 and their grandchildren since 2002. "We recommend that people drink water on a regular basis instead of sugary or artificially sweetened beverages", said Mr Pase. The study examined beverage intake of 2,888 people over the age of 45 for its stroke analysis and 1,484 people over the age of 60 for the studys dementia analyses. It is well known that people with certain health conditions, such as obesity and diabetes, are at higher risk for stroke and dementia.
Pase said that the next steps in the research was to look more closely at the positive food and drinks choices people can make to improve health. A just-released study argues that drinking a lot of artificially sweetened beverages may put you at a higher risk of developing several bad diseases.
"To our knowledge, our study is the first to report an association between daily intake of artificially sweetened soft drink and increased risk of both all-cause dementia and dementia because of Alzheimer's disease", the co-authors added.
It's also possible that people who are at risk of developing vascular issues-say, a stroke-may switch to diet soda as a way to try to control those driving factors, like excess weight or high blood sugar. "It looks like there is not very much of an upside to having sugary drinks, and substituting the sugar with artificial sweeteners doesn't seem to help".
Other recent studies have found health risks that appear to be linked to diet fizzy drinks, such as a link between diet drinks and the risk of metabolic syndrome and type 2 diabetes.
Although there wasn't a definite link between sugary drinks - such as fizzy pop and fruit juices - and dementia or strokes, those who regularly drink them were found to have poorer memories.
He said: "Both sugar and artificially-sweetened soft drinks may be hard on the brain". NYU nutrition expert Marion Nestle tells MedPage Today that those limitations are worth keeping in mind, and that she wishes the authors "had offered a plausible hypothesis for how artificial sweeteners could be causally related to stroke and dementia".
Interestingly, the researchers didn't find any link between stroke or dementia and sugary beverages or regular sodas.
However, the researchers said they took factors such as age, sex, education, daily calorie intake, quality of diet, exercise and smoking into consideration.
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.
The findings are the result of a long-term study on eating habits and vascular disease.