The Northern Manhattan study followed 2500 adults over a ten-year period, ending in 2010. Those who drank diet soda or even a mixture of diet and regular soft drinks had a significantly higher risk of developing heart disease and strokes than those who did not drink sodas at all. Those who just drank regular soda were not mentioned in the article, but their risk would definitely be significant at least in a subgroup with diabetes. Ingestion of diet sodas appeared to be an independent risk factor for vascular disease, taking its place alongside inactivity, obesity, excessive alcohol, hypertension and smoking. What should you drink instead? Lots of water. Maybe some fruit juices now and then, but it is better to eat an apple than to drink a glass of apple juice.
See the Northern Manhattan study, reported by the Associated Press, February 10, 2011.