People with cardiovascular disease should avoid energy drinks loaded with caffeine and taurine, say researchers in the April Annals of Pharmacotherapy. Fifteen healthy adults each drank two cans a day of a popular energy drink with 1,000 mg of the amino acid derivative taurine and 100 mg of caffeine per can for a week. Heart rates increased 8% on average the first day and 11% the seventh day, and blood pressures climbed 8% to 10%. Although these elevations aren't considered dangerous in healthy people, they might be harmful in those with heart conditions. "Consumption of these drinks could, theoretically, be a frequently overlooked cause of altered medication effectiveness or even hospital admissions or emergency department visits," the authors write.