The question is not a straightforward one. First, your doctor will be interested in how your total cholesterol breaks down into the various subfractions, and particularly the LDL (“bad cholesterol”) count. Two patients with identical total cholesterols can have very different LDL numbers. The focus is on LDL because there is clear evidence that patients with lower LDL values, whether achieved naturally or with drugs, are at lower risk for heart attacks and strokes.  

Second, goals will vary according to your risk of having a severe blockage that could cause a heart attack or stroke. The greater the risk, the lower the cholesterol goal.  This means that there is no one goal for LDL for everyone.

Patients who have had a prior heart attack or stroke are at high risk for another event, so the goal for the LDL will be lower. It may be as low as 50 or 70. In patients who have never had a severe blockage in an artery, risk factors that would still lead to a more aggressive goal include male sex, age, diabetes, high blood pressure, and cigarette use.  For patients who have never had a significant blockage, an online calculator can be used to estimate future risk. Sometimes, your doctor will select a medicine based on the expected percentage reduction in cholesterol from the starting value. The percentage reduction goal could range from a 20% reduction to more than 50% depending on the patient. 

How much can I achieve without medicine?

Dietary and lifestyle changes to achieve a better cholesterol profile are worthwhile, but the benefit is typically modest. The typical percent reduction in LDL is 7%. The most commonly used medicines are the statins. These medicines can achieve 20-60% reductions in LDL.

I don’t understand why I should take a medicine when my cholesterol numbers are good?

It is important to note that the average American adult cholesterol numbers are high compared to that of other groups. American children, adults in other societies with different diets and lifestyles and lower risks of heart attacks, and other mammals typically have LDL numbers below 70. This is far lower than the average American adult value of approximately 120. This means that our standards may have been too lax.

Furthermore, there is clear evidence that even patients with lower cholesterol numbers can benefit by lowering the numbers further with medicines. Again, the goals depend on the patient.