Researchers had said that consuming as little as one diet soda a day could increase your risk of heart attack and stroke by 48 percent. The body releases insulin after it “tastes” the sweetness from the artificial sweeteners in the diet soda. Too much of them – without any actual sugar – causes an overload, making the cells less responsive to the hormone. Alcohol can trigger symptoms of atrial fibrillation (arrhythmia), which increases the risk of stroke by five times, according to a study. Excessive alcohol stops the liver from making the materials that help the blood to clot.