In the past two weeks, I have had several doctors’ appointments.  Just routine visits really, checking in with my primary care doctor, neurologist, and rheumatologist, getting new prescriptions, etc.  Part of this process includes routine bloodwork.  My neurology nurse practitioner was the first one to call me with the results of that bloodwork.  Everything looked pretty good except that my vitamin D level remains low (argh) and my cholesterol levels are high.

So today, I thought we’d talk about cholesterol.  What is it?  How is it measured?  Is all cholesterol bad?  Why is too much cholesterol bad?  What can you do to lower your cholesterol?

What is Cholesterol?

Cholesterol is a soft, waxy substance among the lipids (fats) found in the bloodstream and in all body cells. It is used to form cell membranes, produce hormones, and for other bodily functions.  Fats, including cholesterol, cannot dissolve in blood and are transported by lipoproteins.  Too much cholesterol in the blood (hypercholesterolemia ) is a major risk factor for coronary heart disease.

The correct way to have your cholesterol tested is by having a “fasting” blood draw.  For 12 hours before you go to the doctor or lab, you must not eat.  You should drink water to stay hydrated, but food can make the test inaccurate.  In the United States, cholesterol levels are measured in milligrams per deciliter (mg/dL) of blood.  In Canada and the UK, they are measured in millimoles per litre (mmol/L).

My blood results were:

• Total Cholesterol: 205 mg/dL
• HDL (good) Cholesterol: 44 mg/dL
• LDL (bad) Cholesterol: 143 mg/dL
• Triglycerides: 89 mg/dL

In 2006, the respective numbers were 214, 45, 147, and 112.  So everything is just a bit lower, but my neurologist would like to see those numbers lower still.

High-Density Lipoprotein (HDL) or “Good” Cholesterol

Where “good” cholesterol is concerned, higher is better.  HDL levels in the average man range 40-50 mg/dL (1.04-1.30 mmol/L) . In the average woman, they range 50-60 mg/dL (1.30-1.55 mmol/L) .  A low HDL level, which is less than 40 mg/dL (1.04 mmol/L) for men or less than 50 mg/dL (1.30 mmol/L) for women, increases the risk of cardiovascular disease.  Conversely, an HDL cholesterol of 60 mg/dL (1.55 mmol/L) or higher gives some protection against heart disease.

My HDL result at 44 mg/dL (1.14 mmol/L) is too low.  Increasing physical activity and losing weight can both raise HDL cholesterol in the blood.  Smoking, being overweight and a sedentary lifestyle can result in lower HDL cholesterol.  Interestingly, progesterone, anabolic steroids and male sex hormones (testosterone) lower HDL cholesterol levels while female sex hormones raise HDL cholesterol levels.

Low-Density Lipoprotein (LDL) “Bad” Cholesterol