High cholesterol has been linked to the development of coronary artery disease and heart attack. With family history of high cholesterol, it is very unlikely that dietary modification and life style adjustment (exercise, stress reduction, avoiding tobacco) are going to play a substantial role. You have not provided me with your LDL, triglycerides, and HDL levels which are more important in deciding further care. Also, it is important to know whether or not anyone in your family has suffered from a heart attack in the past or needed coronary interventions. If you don't smoke and are not a diabetic and there is no family history of early CAD then based on your age your LDL cholesterol (not total) could be as high as 190. On the other hand, if there is diabetes or other risk factors for coronary artery disease, in the worst case scenario, LDL of 100 or greater would warrant further therapy. I think that at this point you probably should seek medical attention to figure out what you risk is. Certainly, life style modification is the first step in this process no matter what and it won't hurt to start now.
Please read: " Prevent and Reverse Heart Disease " by Caldwell B Esselstyn Jr. Good luck.