LDL-Cholesterol: Particle Size and Density Factor Into Heart Disease

Various molecules are counted and/or calculated when we do blood work. This article will focus on LDL-cholesterol. You may be familiar with LDL as being bad; but this article will show you there is more to heart disease risk than LDL alone. Emerging evidence shows LDL particle size and density play a larger factor than the absolute value of LDL.

This article focuses on LDL-Cholesterol. I have written similar articles about HDL (located here) and triglycerides.

What is LDL-Cholesterol

LDL stands for Low Density Lipoprotein; whereas LDL-C is talking about the cholesterol contained within that lipoprotein.

Think of LDL as a boat:

raft depicting cholesterol and liporproteins

Cholesterol is the cargo:

diagram of a schematic representing cholesterol

The cholesterol (cargo) can’t float in the blood; it needs to be carried around by the lipoprotein (the boat). Remember, lipoproteins are not cholesterol, they are cholesterol carrying molecules. There can be varying amounts of cargo on each boat:

raft depicting cholesterol and liporproteins
raft depicting cholesterol and liporproteins

LDL can carry varying amounts of cholesterol. Generally its better to have lower amounts of LDL-Cholesterol. You'll learn exactly why soon.

LDL and it’s Associations with Increased Risk of Heart Disease

One of the reasons LDL-C is considered “bad” (whereas HDL is ‘good’) is because the cholesterol on the LDL molecule is more susceptible to oxidation and inflammation. To learn more about the misconceptions of cholesterol (and eggs), please click hereto learn why cholesterol was made out to be bad, please click here.

Oxidation and inflammation are the driving forces behind almost all chronic diseases [1], notably heart disease [2].

raft depicting cholesterol and liporproteins

When LDL is exposed to oxidation and inflammation, the cholesterol contained within the LDL molecule is more susceptible to damage, making it more likely to contribute to heart disease. 

When this LDL-C molecule becomes oxidized, it will undergo changes which can clog an artery. In years past, doctors seemed to focus on LDL-C when discussing heart health, but now we know there are many factors that contribute to LDL having a role to play in heart disease.

As I discussed above, inflammation and oxidation are driving forces behind the heart disease, not the LDL itself. So if your doctor says you have high ‘cholesterol’, you can see why it’s important to focus on minimizing oxidation and inflammation, through diet and supplementation.

In addition, LDL is a group of particles of various sizes; it’s not just one unique molecule. In the past, we would group all the various LDL molecules together to assess cardiovascular disease risk. Now we know we need to consider the particle size and density [3] as some LDL molecules carry more risk than others.

LDL Particle Size and Density

As I mentioned above, the total LDL-C count doesn’t tell the whole story – we need to focus on size and density of the LDL-C molecules.

We usually talk about Pattern A versus Pattern B LDL molecules. Pattern A is good; Pattern B is bad. That is, Pattern B is the one that raises heart disease risk. Keep in mind that these molecules exist in a continuum, and there will be some in between these two extremes.  About 25% of those with elevated pattern B inherit this trait, but diet, nutrition and exercise [4] all affect it too.

raft depicting cholesterol and liporproteins

Measure the Ratio of Pattern A to Pattern B

Greater cardiovascular disease risk associated with Pattern B (small/dense) LDL [3]

  • 50% of men with Atherosclerotic Cardiovascular disease have LDL pattern B [4]
  • Pattern B seen more in Type 2 Diabetes, insulin resistance syndrome, chronic anovulation, and PCOS [4]

 Factors That Improve LDL Particle Profile (increase good pattern A and decrease bad pattern B LDL)

  • Low Carb diets [5]
  • High fat diets[6], including eating good quality saturated fat [3], [5]
  • Mediterranean diet[7]
  • Nuts (due to Polyunsaturated Fatty Acids (PUFAs) and Monosaturated Fatty Acids (MUFAs)[7]
  • Flax Seed Oil (due to Alpha Lipoic Acid (ALA) content) [8]
  • Avocados [9]
  • Fish Oils[10]
  • Weight loss and intensive exercise training[11]
  • Avoiding fructose (especially high fructose corn syrup)[12]
  • Avoiding trans fats, margarine [13]

Click here for ways to improve your HDL-C through diet, nutrition and lifestyle modifications.

Looking Beyond LDL-C to Assess Heart Health

In the past, many doctors would prescribe medications simply off a high LDL-cholesterol. New guidelines advise doctors to assess other factors and “physicians now have to shift their thinking away from only looking at cholesterol levels” [14].

To fully assess heart health, blood tests must be used in conjunction with blood pressure, blood sugar regulation, smoking, exercise, stress and family history. It is based on these factors (and more) that doctors should be basing their treatment decisions. It’s no longer acceptable for a slightly elevated LDL-C to warrant aggressive treatment (such as statins) [14].

I can’t tell you what numbers you should aim for, because there are many factors that contribute to overall risk. Your primary care physician (naturopath or medical doctor) can determine your individual risk and then determine your optimal lipid numbers and subsequently the best treatment plan for you.

For now, you can click here to learn how and why we calculate your risk individually.

Conventional Blood Tests and Limitations

 Basic lipid panels will include LDL-C, HDL-C, total cholesterol and triglycerides. These are the most common, basic panels run by doctors.

Total LDL-C is routinely done, but identifying pattern A vs pattern B is not usually tested. LDL-C is usually determined via a calculation (not a direct measurement). It is calculated by the Friedewald equation: LDL-C = (total cholesterol – HDL-C) – TG/5 [4]. This calculation is only valid when the person is fasting. It becomes increasingly less accurate as triglycerides go above 200 mg/dL, and is invalid if triglycerides exceed 400 mg/dL. For high risk individuals, including those with diabetes and vascular disease, or those with triglycerides above 200 mg/dL, it is advised to measure LDL-C directly [4].

As I mentioned above, treatment cannot rely on these basic values alone – sometimes further testing needs to be done. I use Doctor’s Data Comprehensive Cardiovascular Risk Assessment, which includes the above mentioned markers plus LDL particle size/density information, oxidized LDL levels and inflammatory markers (plus more). In order to properly assess the situation, and before commencing on lifelong treatment protocols, patients would benefit from understanding their true risk.  Click here to learn more about this test.

References