Heart disease was the No. 1 cause of death in the United States in 2007. It claimed 616,067 lives, about a quarter of all deaths in the United States. A number of conditions fall into the category of “heart disease,” including coronary artery disease — the most common type of heart disease — and problems with heart rhythm. Risk factors include obesity, smoking, high blood pressure, diabetes and high cholesterol, according to the CDC, and lowering your cholesterol and blood pressure may reduce your risk of dying from heart disease.