What is a good ratio of LDL to HDL?

An ideal ratio of LDL — known as bad cholesterol — to HDL — or good cholesterol — is 3.5 to 1 millimoles per liter, according to Mayo Clinic. In general, a ratio of 5 to 1 millimoles per liter or lower presents no cause for concern.

Although the ratio of LDL to HDL is helpful in assessing a person's health risk, the LDL levels in conjunction with the total cholesterol number are of greater significance in preparing a treatment plan for cardiac risk, as further explained by Mayo Clinic. In some cases, lifestyle changes alone are sufficient to treat dangerously high cholesterol, while other situations may require intervention with medications, as reported by the American Heart Association.