When doctors order traditional lipid panels as part of annual blood tests, patients see “non-HDL” and often ask, “What is non-HDL cholesterol?”
The question reminds me of reading Shakespeare’s “King Henry IV” in high school.
In the play, the character Prince Hal has five different names. This confused me until I realized all those names refer to the same person. Once I understood that, the play and plot became clearer.
The terminology used in medicine influences our comprehension and treatment options. Non-HDL is one of the least understood characters in the cholesterol metabolism “play.”
Blood Is Like “Oil and Water”
Our blood isn’t a homogenous liquid. It’s more like an oil and vinegar salad dressing. In this example, the water component of our blood is the “vinegar,” and the fat is analogous to the oil.
Fat doesn’t dissolve in water. Therefore, the fat forms little protein- and phospholipid-covered balls suspended in the blood.
Cholesterol’s Purpose and “Cast of Characters”
There’s no such thing as “good” cholesterol or “bad” cholesterol. A cholesterol molecule is exactly the same whether it’s contained in a “good” HDL particle or a “bad” LDL particle. We need cholesterol to build cell walls, manufacture hormones such as testosterone, and make bile acids to digest our food. Too much cholesterol in the wrong place, such as the walls of our arteries, confers its “badness.”
Understanding the “characters” that comprise the “play” of cholesterol metabolism is helpful.
“Main Characters”
HDL and LDL are the “main characters” featured in cholesterol. You’ll see them on your lipid panels.
- LDL (low-density lipoprotein):
- It carries cholesterol from the liver to cells and the rest of the body.
- It can carry excess cholesterol to arterial walls to create dangerous buildup.
- HDL (high-density lipoprotein):
- It carries cholesterol from the body back to the liver for reprocessing.
- It reduces the amount of cholesterol deposited on arterial walls, where it can cause damage.
“Supporting Characters”
The following are some “supporting characters” to help you better understand cholesterol.
- VLDL (very low-density lipoprotein):
- It primarily contains triglycerides and very small amounts of cholesterol.
- VLDL transports triglycerides from the liver out to the body.
- Your body uses these triglycerides for immediate energy in muscles or energy storage in fat cells.
- IDL (intermediate density lipoprotein):
- As a VLDL particle delivers its triglycerides, it becomes proportionally richer in cholesterol and becomes an IDL particle.
- Chylomicron (ultra-low-density lipoprotein):
- It’s primarily a triglyceride-containing particle that transports fat from the gut to the blood.
What Is Non-HDL Cholesterol?
Non-HDL cholesterol is your total cholesterol minus HDL cholesterol. In other words, non-HDL cholesterol is the sum of LDL, VLDL, IDL, and chylomicron.
Why Measure Non-HDL?
Non-HDL cholesterol is easy, cheap, and convenient to measure. It’s a better predictor of coronary artery disease risk than LDL alone — especially when LDL isn’t elevated.
The Crucial Role of Lipoprotein B-100
Returning to the oil and water analogy, you might imagine a chaotic mix of tiny balls floating through your bloodstream. However, that’s not the case.
Each ball has a set of lipoprotein markers that identify its contents and the route it must take through the body to arrive at its designated location. Think of it like a passport.
A single lipoprotein called B-100 (“APOB”) occurs on each non-HDL particle.
Why is it important?
All non-HDL particles confer risk because they contain cholesterol, and blood vessel walls can absorb them. This means non-HDL cholesterol is potentially atherosclerotic and can contribute to cardiac disease.
Today’s Takeaways
Gaining a better understanding of lipid physiology and your lipid panel is beneficial for reading lab results and becoming more informed. This way, you won’t need to ask, “What is non-HDL cholesterol?”
Banner Peak Health employs non-HDL (or APOB) because it’s the most accurate risk assessment tool. The more accurately we can gain insight into your atherosclerotic risk, the more accurately we can target and mitigate that risk. Maintaining and improving your health is always our priority.
