More than 50 million Americans suffer from high blood pressure, which can lead to things like heart attack, stroke, and kidney disease.
Researchers in Boston studied more than 150,000 women over 12 years to see if they could establish a connection between caffeine and the risk of high blood pressure, and what they found is very surprising. Colas, even diet ones, can increase a woman's risk for hypertension, but here's the weird part...they found that coffee does not pose the same risk.
"Given that the findings are opposite...if you look at coffee versus cola beverages, it's likely that caffeine is not the culprit here," says Dr. Wolfgang Winkelmayer, with Harvard Medical School.
A cup of coffee has three times as much caffeine as a can of cola, but the women in the study who drank the most coffee had the lowest risk of high blood pressure. So one theory is that other anti-oxidants in coffee may offset the problem and protect the heart, because the study found that women who drank four or more cans of cola a day were 28% to 44% more likely to be diagnosed with hypertension than those who just had one can of cola a day.
Studies continue now to see if there might be something else in cola that raises blood pressure.