Confused about my cholesterol numbers! Recent bloodwork shows a good LDL of 104 and an excellent HDL of 93, with a very good cholesterol to HDL ratio of 2.38. Triglycerides are only 122. Yet, my total cholesterol calcuates to a 221, which is 10% over the American Heart Association’s recommended level. How can four numbers that are so good add up to an overall cholesterol reading that is too high?

The formula for calculating the cholesterol values are as follows:

Total Cholesterol = LDL + HDL + (Triglycerides/5)

Normal lab values vary from institution to institution but the following values are generally accepted as normal:
Total Cholesterol < 200 mg/dl
HDL cholesterol > 30 mg/dl
LDL cholesterol 65 – 180 mg/dl
Triglycerides 45 – 155 mg/dl

In terms of your lab results, an LDL of 104 mg/dl is acceptable and an HDL of 93 is considered to be protective of cardiovascular disease. In addition, you have a Triglyceride value of 122 which is desirable. Each individual is different and the AHA recommended levels for cholesterol results are more like guidelines averaged over tens of thousands of patients. In other words, your HDL level of 93 – an excellent number – appears to artificially inflates your total cholesterol number.

I would focus more on the overall picture (HDL, LDL, triglycerides) than on one lab value (total cholesterol) as your cardiac risk is multifactorial. This NIH website is an excellent resource for you to calculate your 10-year cardiac risk: http://hp2010.nhlbihin.net/atpiii/calculator.asp