Video | Understanding Cholesterol | Cholesterol Uses | Inflammation and Cholesterol | LDL Particle Size | What to Do

A paper published in 2022 shows low-carb dieting to be beneficial for 12 of 13 cardiovascular risk factors (1).

The one outlier is LDL cholesterol, which can increase on a low-carb or keto diet. Why does that happen, and is it a deal breaker when it comes to following a keto diet? This blog post addresses those questions and builds your understanding of cholesterol. 

Cholesterol and Keto Simplified [Video]

In this video, you’ll learn…

• What cholesterol is and why it is useful.
• The relationship between cholesterol and inflammation.
• What to do if your cholesterol goes up while on the keto diet.

Understanding Cholesterol

To start with, you need to know that your body needs cholesterol. It is a part of every cell membrane and an essential part of your hormones like estrogen and testosterone. The goal is never to get your total cholesterol to zero.

Cholesterol Levels

When you get your blood tested, you see your total cholesterol level.

Total cholesterol is a calculation that the lab gets by adding your HDL and LDL cholesterol levels together with 20 percent of your triglyceride level.

Triglycerides are a type of fat found in your body.

And, you might know HDL as the “good” cholesterol and LDL as the “bad” cholesterol.

HDL and LDL are abbreviations; their real names are High-Density Lipoprotein and Low-Density Lipoprotein. So, they are both lipoproteins.

If you look closely at that name, you see that it is a combination of two words: lipid and protein.

A lipoprotein is a mixed molecule containing fat and protein. Fat can’t move through your blood unless it has something to carry it, and that something is this nice neat lipoprotein package.

An important early takeaway is that the primary job of both HDL and LDL is to carry fatty substances, namely cholesterol and triglycerides, through your blood.

It is the direction in which these lipoproteins carry cholesterol that gives them the reputation of being good or bad. Let’s take a look at that.

Understanding HDL

HDL is the housekeeper. It gathers cholesterol from your body and then heads for your liver, where it drops off its cargo.

The dumped cholesterol is either recycled or turned into bile acids and excreted. 

Understanding LDL

LDL works in the opposite direction. These molecules carry cholesterol out into your body, which is not necessarily a bad thing, and we’ll get to that later.

VLDL particles contain cholesterol but are mostly filled with triglycerides.

Those triglycerides are used for energy or stored in tissues like muscles and adipose tissue. So, when the VLDL particles leave the liver, they quickly drop many of their triglycerides into cells, turning VLDL into LDL. 

Therefore, LDL particles don’t have as many triglycerides as VLDLs, but they do have some. They also have cholesterol on board. LDL is still carrying fatty cargo.

LDL Particles (Cruise Ship Analogy)

To drive that point home, I like Dave Feldman’s analogy using LDL particles as cruise ships. 

In his video, he asks you to imagine an LDL particle as a cruise ship where the passengers are triglycerides and the lifeboats are cholesterol.

As the LDL ship cruises through your blood, it drops off triglyceride passengers at different locations.

Cruise ships also have lifeboats; in the analogy, we see that the lifeboats represent cholesterol.

Lifeboats go along for the ride. The ship’s captain could drop them off if needed somewhere, but if not, they return to port, which is your liver.

In your liver, the entire cruise ship, along with its unused cholesterol, is taken out of service, and the cholesterol is recycled or prepared for excretion.

What would cause your body to need these lifeboats?

In other words, what might your body need cholesterol for? 

Cholesterol – A Useful Molecule

I mentioned at the beginning that your body needs cholesterol. It is a very useful molecule and essential in hormones, cell membranes, and different metabolic materials.

Cholesterol is also an important component of wound healing within your blood vessels, where it acts much like a Band-Aid.

You might wonder how you can hurt a blood vessel to the point where it needs a Band-Aid.

Well, this damage typically comes from inflammation. Many lifestyle habits and conditions lead to inflammation. One of the most significant contributors is a poor diet that contains inflammatory foods, such as refined carbs, sugar, and high fructose corn syrup. These ingredients are commonly found in processed foods and soda.

Understanding Inflammation and Cholesterol

When chronic inflammation is present, it causes rough patches in the lining of blood vessels.  Cholesterol then rushes over to help repair those damaged areas.

This rush to help is where cholesterol gets its bad reputation because as cholesterol fills in those areas, the lumen or hole through which the blood passes gets narrower, increasing your risk of cardiovascular disease.

Cholesterol – The Innocent Good Samaritan?

Plaque in the arteries is bad, but are we blaming the wrong culprit?

We seem to blame the Band-Aid when, in reality, what caused the problem was inflammation.

Yes, LDL carries cholesterol out into your body, but if there is no need for it, it stays on the “cruise ship” and returns to your liver, where it gets broken down, reused, or excreted.

The question becomes, is cholesterol completely innocent? In other words, is it okay to have a super high total or LDL cholesterol level?

The answer is no. As I mentioned at the beginning, LDL cholesterol is one of the 13 cardiovascular risk factors. However, the idea of LDL cholesterol as a single causative factor needs more scrutiny.

We need to dig deeper to understand what’s really going on if your LDL cholesterol level is not coming down or is going up despite following a healthy, low-carb, low-sugar diet.

Cholesterol and Keto

Remember that at its most basic level, LDL particles act as ships carrying fat. It makes sense that the more fat you eat or burn, the more LDL ships you will have in your blood. 

While it doesn’t happen to everyone, elevated total and LDL cholesterol is not unusual when following a high-fat, rapid fat-burning diet like keto.

It is also worth noting that these elevated levels may be more prevalent in someone who has an underlying issue like insulin resistance or diabetes. They can also be more pronounced in those with a genetic propensity toward high cholesterol, particularly when their saturated fat intake is increased.

In a past blog post on low-carb dieting and cholesterol, I discussed how to determine whether you have a genetic propensity to high cholesterol.

LDL Particle Size

I’m going to add one more wrinkle to this discussion by noting that not all LDL particles are created equal. You want large and buoyant LDL particles, not small, dense ones. Small, dense LDL particles carry the greatest health risks because they can better penetrate the arterial wall. 

To really tell if your elevated LDL finding is dangerous, you need an additional blood test that goes beyond the standard lipid panel.

An NMR LipoProfile or Nuclear Magnetic Resonance LipoProfile does that. It is a blood test that reveals the sizes of your lipoproteins. In other words, are your LDL particles large and buoyant or small and dense.

The large buoyant ones are safer because they float more easily in your bloodstream and have a lower chance of becoming oxidized. Oxidation is a process that triggers inflammation and accelerates the development of atherosclerotic plaques.

The small, dense ones are more dangerous because they can more easily slip between the cells that line the arteries and are more prone to oxidation. 

What Determines LDL Particle Size?

Several factors influence LDL particle size, including genetics, physical activity, and diet. Diets high in refined carbohydrates, sugar, and high-fructose corn syrup tend to promote the formation of small, dense LDL particles, whereas diets rich in healthy fats tend to encourage larger, buoyant LDL particles​. 

This post is focused on keto dieting, which, by definition, is low in refined carbs and sugars. Healthy fats include avocados, nuts, seeds, and fatty wild-caught fish. Unhealthy fats include trans fats, hydrogenated oils, and vegetable or seed oils, which are industrial fats found mainly in fried and processed foods. 

Just an additional note on saturated fat: earlier, I mentioned that saturated fat can raise LDL cholesterol, especially in those who have a genetic propensity toward it. That is true. 

However, we see from a National Library of Medicine review study that “the changes in LDL-C do not take into account the overall changes in the entire lipoprotein profile. For example, saturated fat appears to decrease small-dense LDL (sdLDL) and increase large buoyant LDL,” which is the desired pattern (2).

What to Do 

If your cholesterol level goes up or remains high on a keto diet, here are some things to do. 

1. Take Note but Don’t Panic

LDL cholesterol is a cardiovascular risk factor, but it is one of 13 identified risk factors. To fully assess your risk, you want to do a more thorough evaluation, and for that, you need to ask your doctor for additional blood tests.

2. Ask for Additional Blood Tests

In addition to the standard lipid panel, request fasting blood glucose, HbA1c, high-sensitivity CRP, and NMR lipoProfile test.

Fasting glucose and A1c can indicate insulin resistance and diabetes, both of which are correlated with LDL cholesterol levels. High-sensitivity CRP measures general levels of inflammation in your body. And the NMR LipoProfile test reveals the sizes of your lipoproteins.

3. Make Treats Special, Not Ordinary

Also, don’t take shortcuts on your diet. The occasional fast-food meal or candy bar will not do you in. But these fried and processed foods cannot be a part of your regular diet. Keep treats special, not ordinary. You cannot outrun a poor diet. The damage may take decades to show up, but it will show up. 

Thank you for reading and have a wonderful week!

References:

(1) Diamond, David M., Benjamin T. Bikman, and Paul Mason. “Statin therapy is not warranted for a person with high LDL-cholesterol on a low-carbohydrate diet.” Current Opinion in Endocrinology, Diabetes and Obesity 29.5 (2022): 497-511.

(2) DiNicolantonio, James J., and James H. O’Keefe. “Effects of dietary fats on blood lipids: a review of direct comparison trials.” Open heart 5.2 (2018): e000871.

About the Author

Becky Gillaspy, DC, is the author of The Intermittent Fasting Guide and Cookbook and Zero Sugar / One Month. She graduated Summa Cum Laude with research honors from Palmer College of Chiropractic in 1991.