The only way to find out if you have high cholesterol is to have a blood test. You can have high cholesterol for many years without feeling its effects. In fact, most people with high cholesterol feel no different than those without it.
If you are 19 or older, then you should have a cholesterol test once every five years. But, if you are already at risk for heart disease, your medical professional will probably wish to look at your situation more closely.
The more risk factors for heart disease you have, the lower your cholesterol needs to be. If you are over the age of 55 for men and 65 for women or if an immediate family member died of heart disease before those ages, use tobacco products, have high blood pressure, have diabetes, are overweight and/or lead an inactive lifestyle, your health care provider will likely recommend treatment for you at a lower cholesterol level than someone who doesn't have any heart disease risk factors.