there are a lot of known risk factors for heart disease and cancer. unfortunately, risk factors are not predictors. one person can have "high" cholesterol and be healthy, and another can have "normal" or "low" cholesterol and have a heart attack. in fact, the people with "high" cholesterol don't have more heart attacks than the people with "normal" cholesterol. risk factors are associated with a disease, but, of course, might only be secondary symptoms.