An estimated 25% of all Americans have one or more risk factors for heart disease, increasing their risk for heart attack. Most risk factors for heart disease are related to lifestyle. Some risk factors, (such as age, gender, and ethnicity) cannot be changed. Nevertheless, overall risks can be reduced with healthy lifestyle changes. Dr. David C. Kolbaba explains why 50% of heart attack victims have none of the standard risk factors associated with heart attacks such as smoking, elevated cholesterol levels, obesity and genetics.