Keto Bombs #4 — Cholesterol (Good or Evil?)

A quick exploration of the confusing term cholesterol

Stanislav Kozlovski
Nov 6, 2019 · 4 min read
Photo by Suganth on Unsplash

Keto Bombs are a series of short, concise and informative pieces on various aspects of the Ketogenic diet.

holesterol is a complex topic. Throughout the last 70 or so years we thought that it was strictly related to bad, life-threatening conditions like heart disease and avoided it like the plague.
Saturated fat was deemed the most unhealthy macronutrient. People suddenly started preferring heavily-processed low-fat products with added sugar instead of their natural counterpart.


Back in the 1950, the heart lipid hypothesis speculated that there was a strong link in between cholesterol and heart disease. Due to the accumulation of evidence at the time, it was widely accepted by the medical community.

There is controversy around these studies. Some people argue that they cherry-picked results in their favor and were swayed by political agendas, following the money in order to sell products that are easier to produce in mass quantities (margarine, high-fructose corn syrup).


Cholesterol is a fatty substance that is vital to our health. It is a crucial building block in cell membranes and is needed to make vitamin D, essential hormones (testosterone/estrogen) and fat-dissolving bile acids.
It is made mainly by our liver, with normally only ~20% of it coming from our diet.

There are two main types of cholesterol — low-density lipoprotein (LDL) and high-density lipoprotein (HDL). In fact, these are not cholesterols by themselves. They are actually carriers of cholesterols — a mix of lipids (fats), cholesterols and proteins, hence the name, lipoproteins.

LDL (“bad” cholesterol) — what goes around and delivers cholesterol to the cells.
HDL (“good” cholesterol) — what goes around and picks up the excess cholesterol, delivering them back to the liver for excretion.


The low-density lipoprotein unfortunately got all of the flak from the health industry. It is labelled as the bad cholesterol and the one we want less of. Let’s examine it further:

LDL, apart from carrying the vital cholesterol, is meant to also carry triglycerides.
triglycerides — the storage form of fat. When you eat, your body converts any calories it doesn’t need right away into triglycerides.
Triglycerides are important — we need something to carry them throughout the body so that we can burn them! If LDL did not exist, we would not be able to ever burn fat.

There are three types of low-density lipoproteins:
VLDL (very low-density lipoprotein) — Made by the liver, these are lipoproteins rich with triglycerides.
IDL (intermediate-density lipoprotein) — These are VLDLs with some of their triglycerides removed. Some IDLs are removed by the liver and some converted into:
LDL (low-density lipoprotein) — the end result, the lipoprotein with the least amount of triglycerides in it. It is the purest form of cholesterol.
LDL travels through the bloodstream and goes to the specific site it’s meant to. Our cells have LDL receptors which collect the LDL particle.

Is LDL all good, then?

Not exactly. When LDL reacts with sugar in the blood stream, a processes called glycation occurs.
glycation — where cholesterol and sugar form into a harder and denser lipoprotein.
Glycation oxidizes the LDL and changes its structure. Because of this, it is thought that it cannot be accepted by the cells’ receptors and is left floating around in the bloodstream.
They eventually get picked up by the arterial wall. Inflammation occurs and white blood cells flood the area, resulting in plaque.

Keto’s role

Following that logic, the keto diet turns out to be great at controlling arterial plaque built by mutated LDL.
Since the actual culprit turns out to be sugar paired with LDL, keto naturally avoids this by not having sugar in the first place!
Further, since inflammation causes the white blood cells to flood the area, the ketogenic diet’s inflammation lowering effect helps prevent such plaque buildup.

Photo by Danting Zhu on Unsplash


In summary, we realize that cholesterol is not bad as of its own — it actually turns out to be quite healthy, aiding in vital processes like fat burning and hormone/vitamin production.

We briefly noted the different types of cholesterol and exposed the big caveat in the story — sugar and how it mutates the LDL particle, ultimately causing it to get stuck in the arterial walls.
Said LDL becomes inflamed and swells with white blood cells that actually clogs your artery.

Luckily, beta-hydroxybutyrate (BHB), a ketone body we produce while in ketosis, helps reduce inflammation massively.
More luckily, we do not eat sugar on the ketogenic diet.

Practical Note

This is a very complex subject and there is a lot more to be said on the matter. Our short articles are not meant to go in depth, but rather introduce you to the topic. We can recommend three books for diving deeper into the subject matter:
The Big Fat Surprise by Nina Teicholz
The Great Cholesterol Myth by Johny Bowden, Stephen T.Sinatra
Grain Brain by David Perlmutter, Kristin Loberg

Let me leave you with a quick thought experiment — can you think of a naturally-occurring food that contains both fat and sugar in it?

Keto Bombs


Your guide to living a SUGAR FREE low-carb lifestyle.

Stanislav Kozlovski

Written by

A generally curious individual — software engineer, regular gym-goer and coffee lover


Your guide to living a SUGAR FREE low-carb lifestyle.

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