Cholesterol, Genetics, and Arterial Health: Why High Levels Aren’t Always Harmful
For years, a high cholesterol number on a lab report felt like a verdict. I remember sitting across from a doctor who looked at my numbers and reached straight for a prescription pad without asking a single question about what I ate, how I slept, or whether my blood sugar was steady. That moment stuck with me, because it's exactly the kind of conversation that happens to women every day, and it rarely gets challenged.
So let's challenge it. Understanding what cholesterol actually is, and how your body manages it, changes how you read your own labs. It also explains why two people can carry the same number and land in completely different places health-wise.
Cholesterol is not optional
Your body needs cholesterol to function. It builds every cell membrane you have, forms the backbone of your sex and stress hormones, drives your production of vitamin D, and makes the bile acids that let you digest fat. Nothing on that list is optional.
Your liver makes most of the cholesterol circulating in your body, and it adjusts output constantly based on what you need. When hormone production rises, when cells need rebuilding, when bile acid demand goes up, your liver responds by making more. When intake from food goes up, your liver slows its own production to compensate. This feedback loop is a large part of why eating cholesterol rich foods, eggs included, has such a limited effect on blood cholesterol for most people. Your body is built to regulate this tightly, and it does.
Your genes set your baseline
This is the part most people never hear. Genetics shape how many LDL receptors your liver cells carry, how efficiently those receptors pull cholesterol back out of your blood, and how your body handles ApoB, the protein that rides on the particles carrying cholesterol through your bloodstream. Variants in genes like LDLR, APOB, PCSK9, and HMGCR explain a real share of why one person runs a cholesterol level of 150 and another runs 240 while eating almost identically.
Familial hypercholesterolemia is the clearest illustration of this. In that condition, the LDL receptor pathway doesn't clear ApoB particles efficiently, so cholesterol runs high from birth regardless of diet. Lp(a), another cholesterol carrying particle, is also driven mostly by genetics and worth knowing once, since it tracks with risk independent of what you eat.
A high number by itself is not the whole story
Cholesterol is part of how your body repairs and rebuilds. Tissue calls for it during healing, hormone production, and growth. LDL carries cholesterol and fuel to your cells, HDL and your liver bring the extra back for reuse or removal, and this cycle runs constantly whether you're thinking about it or not.
In someone with low inflammation and good insulin sensitivity, a higher LDL number on its own tracks poorly with actual cardiovascular events compared to markers that tell a fuller story, like ApoB particle count, your triglyceride to HDL ratio, and high sensitivity CRP. This is why I stopped looking at total cholesterol as the headline number a long time ago.
What actually damages your arteries
Cholesterol doesn't clog anything on its own. What damages your arteries is a sequence of events, and cholesterol only shows up because it's part of the repair response called in after the damage starts.
It begins with injury to the delicate lining of your blood vessels, caused by high blood pressure, smoking, chronically elevated blood sugar, and ongoing inflammatory stress. Once that lining is compromised, ApoB carrying particles, including VLDL remnants, IDL, LDL, and Lp(a), can get trapped inside the vessel wall. That retention is the real first step toward plaque, not the presence of cholesterol itself.
From there, trapped particles oxidize, and oxidized lipids trigger your immune system to respond. High blood sugar makes this worse by glycating LDL, a process that makes it easier to oxidize and harder for your body to clear. Your immune cells then consume these damaged particles and become what's known as foam cells, and over time that buildup becomes fatty streaks and eventually plaque. The more ApoB particles you're carrying, the higher the odds that some get trapped in this process, and small dense LDL particles tend to penetrate and oxidize fastest in a body already dealing with high blood sugar and a diet heavy in seed oils.
What Bart Kay adds to this conversation
Bart Kay taught cardiovascular and respiratory physiology, exercise physiology, and nutrition at the university level for years, and his work in metabolism and lipid transport is part of why I trust his read on this topic. He pushes back hard against the idea that a high cholesterol number is automatically dangerous, and the physiology backs him up. Your body regulates cholesterol tightly, your genetics set a real baseline, and a high number in isolation tells you far less than most doctors imply.
Kay's focus lands on the actual mechanism of harm: ApoB particles getting retained in an injured arterial wall, oxidized, and glycated by high blood sugar in a body running chronic inflammation. That's the process that damages arteries. Cholesterol is present because it's doing its job, not because it started the fire.
This is also where I think the conventional approach gets it backwards. Statins lower a number without addressing the environment that made that number dangerous in the first place, if it was dangerous at all. Blood sugar stays high, inflammation stays high, the diet stays full of seed oils and refined carbohydrates, and a drug gets layered on top instead of the root cause getting addressed. That's worth questioning, and it's a big part of why I focus on the metabolic environment rather than chasing a single number.
What's actually worth testing
Total cholesterol tells you very little on its own. If you want a real picture of your risk, ask your doctor about ApoB, which gives you a direct count of the particles that can actually get lodged in your artery walls. Add your triglyceride to HDL ratio, since a lower number tracks with better insulin sensitivity. High sensitivity CRP gives you a window into inflammation. Fasting insulin or HOMA-IR catches insulin resistance even when your glucose still looks normal. Lp(a) is worth checking once since it's largely genetic. And don't overlook blood pressure and smoking status, since both injure the vessel wall directly regardless of what your lipid panel says.
Where this leaves you
If your cholesterol runs high and your triglycerides are low, your HDL is solid, your blood pressure is normal, and you don't smoke, that pattern often reflects a genetic set point working exactly as it should, not a disease in progress. If your ApoB is high alongside high inflammation, that's the combination that actually raises risk, and it's worth taking seriously.
The fix, in both cases, comes back to the same foundation. Keep your blood sugar steady by building meals around protein, natural fat, and low starch vegetables, and leaving sugar and refined grains out. Swap seed oils for butter, olive oil, avocado oil, tallow, or ghee. Eat seafood regularly for omega-3s. Walk daily, add resistance training, and keep a healthy waistline. Protect your blood pressure by sleeping well, addressing sleep apnea if it's present, limiting alcohol, and not smoking. Get morning sunlight and manage stress in whatever way genuinely works for you. Then track the markers that actually matter, ApoB, triglycerides, HDL, hs-CRP, fasting insulin, and blood pressure, and recheck them after you've given these changes real time to work.
You don't need to fear a number on a page. You need to understand what's driving it.
Frequently Asked Questions
Is high cholesterol always dangerous? No. A high LDL number alone, in someone with low inflammation and good insulin sensitivity, tracks poorly with cardiovascular events compared to markers like ApoB, triglyceride to HDL ratio, and hs-CRP.
Does eating cholesterol raise my blood cholesterol? For most people, only modestly. Your liver adjusts its own cholesterol production based on how much you take in through food, which is why dietary cholesterol has a limited effect on blood levels for the majority of people.
What should I ask my doctor to test instead of just total cholesterol? Ask for ApoB, triglyceride to HDL ratio, high sensitivity CRP, fasting insulin or HOMA-IR, and Lp(a) once. These give a far clearer picture than total cholesterol alone.
Do statins address the real cause of arterial damage? Statins lower LDL, but they don't address blood sugar, inflammation, or the quality of fats in your diet, which are the factors that actually drive ApoB particles to get retained, oxidized, and turned into plaque.
References
Feingold, K. R. (2024). Introduction to lipids and lipoproteins. In Endotext. MDText.com, Inc.
Ference, B. A., et al. (2017). Low-density lipoproteins cause atherosclerotic cardiovascular disease. European Heart Journal, 38(32), 2459-2472.
Sniderman, A. D., et al. (2019). Apolipoprotein B particles and cardiovascular disease: a narrative review. JAMA Cardiology, 4(12), 1287-1295.
Nordestgaard, B. G. (2016). Triglyceride-rich lipoproteins and atherosclerotic cardiovascular disease. Circulation Research, 118(4), 547-563.
Utermann, G. (1989). The mysteries of lipoprotein(a). Science, 246(4932), 904-910.
DiNicolantonio, J. J., & O'Keefe, J. H. (2018). Omega-6 vegetable oils as a driver of coronary heart disease: the oxidized linoleic acid hypothesis. Open Heart, 5(2), e000898.
This article is for informational and educational purposes only and does not constitute medical advice. Please consult a qualified healthcare provider before making changes to your diet or medication, particularly if you have a diagnosed cardiovascular condition or take cholesterol lowering medication.
