Cardiologists are calling for a closer examination of the relationship between diet and heart disease after a recent study showed the Mediterranean diet could be a powerful tool to prevent cardiovascular disease and death. The result could be better recommendations more grounded in science. "As we go on, we realize we know less and less," said Dr. Michael Lauer, director of the division of cardiovascular sciences at the National Heart, Lung and Blood Institute. "We can despair and just make things up, or we can celebrate and say we have a real opportunity to grow here."