whether it's sugary or diet: High consumption of carbonated soft drinks significantly increases your risk of stroke, research shows.Although many studies have shown that a high consumption of sugary soft drinks increases the risk of everything from diabetes and gout to obesity and heart disease, no one had studied the connection between soda and strokes until a study published in the American Journal of Clinical Nutrition in 2012.
Researchers from the Wellness Institute of the Cleveland Clinic, Brigham and Women's Hospital and Harvard Medical School collected health and soft drink consumption information from 43,371 men who were participating in the Health Professionals Follow Up Study and 84,085 women who were participating in the Nurses' Health Study. The men were followed for 22 years (from 1986 to 2008), and the women for 28 (from 1980 to 2008).
The researchers found that participants with higher consumptions of both sugar-sweetened and low-calorie soda were significantly more likely to suffer from strokes. In contrast, consumption of caffeinated and decaffeinated coffee was correlated with a lower stroke risk.
"Greater consumption of sugar-sweetened and low-calorie sodas was associated with a significantly higher risk of stroke," the researchers wrote. "This risk may be reduced by substituting alternative beverages for soda."
The researchers also found that regular consumption of sugar-sweetened soda was correlated with higher blood pressure, higher cholesterol, less physical activity, and higher consumption of red meat and whole-fat dairy products, and regular consumption of low-calorie soda was associated with higher rates of obesity and chronic disease. Yet the contribution of soda consumption to strokes remained even after the researchers adjusted for interference from these other factors.
"According to research from the USDA, sugar-sweetened beverage consumption has increased dramatically in the United States over the past three decades, and it's affecting our health," researcher Adam Bernstein said. "These findings reiterate the importance of encouraging individuals to substitute alternate beverages for soda."
Diet soda just as bad
The reasons for the observed increase in stroke risk remain unclear. For sugary sodas, part of the explanation may stem from the fact that such beverages produce rapid increases in blood sugar and insulin, which in turn can lead to insulin resistance and inflammation, and from there to cardiovascular damage.
"Soda remains the largest source of added sugar in the diet," Bernstein said. "What we're beginning to understand is that regular intake of these beverages sets off a chain reaction in the body that can potentially lead to many diseases - including stroke."
But sugar cannot explain the correlation between the consumption of diet soda and the risk of stroke. Another study, conducted by researchers from the University of Miami at Columbia University and published in the Journal of General Internal Medicine in 2012, found that people who consumed one or more diet sodas per day were significantly more likely to have a stroke or heart attack and to die from cardiovascular disease than people who consumed less diet soda.
As in the Harvard study, diet soda consumption was linked with certain cardiovascular risk factors including high blood sugar, high blood pressure, greater central obesity and former smoking status. But once again, the increased stroke risk was shown to be independent of these factors.
These findings mirrored the results of an earlier study, published in the journal Diabetes Care, which found that daily diet soda drinkers were actually more likely to develop diabetes and metabolic syndrome (a cluster of symptoms linked with an increased risk of diabetes and heart disease).
