Apolipoprotein B (apoB)

Apolipoprotein B (ApoB) is an important component of many lipoproteins that are involved in atherosclerosis and cardiovascular disease.

Atherosclerosis may be described as a chronic inflammation in the arterial wall. It is caused by a complex interplay between lipoproteins, white blood cells (macrophages), the immune system and the normal elements of the arterial wall.

Apolipoprotein B (apoB)This process leads to formations of atherosclerotic lesions or plaques that may protrude into the lumen of the artery causing arterial narrowing, which may ultimately limit blood flow.

If this occurs in the coronary arteries, it may cause angina pectoris and if it occurs in the arteries of the legs, it may cause claudication.

Rupture of an atherosclerotic plaque may lead to thrombosis (blood clotting) causing an acute occlusion (blockage) of the artery. If this happens in a coronary artery it may cause an acute myocardial infarction (acute heart attack).

There are many factors that contribute to atherosclerosis, one of which is elevated blood levels of cholesterol.

Cholesterol and Lipoproteins

Although cholesterol is an essential substance, elevated plasma levels appear to play an important role in the initiation and progression of atherosclerosis. In animal models, atherosclerosis will not occur in the absence of greatly elevated levels of plasma cholesterol.

High levels of plasma cholesterol also appear to be an important contributor to atherosclerosis in humans, although the threshold level of plasma cholesterol that must be exceeded to produce clinically relevant disease appears to be much lower than that in animal models, possibly because lesion formation occurs over many decades.

Atherosclerotic clinical events, such as myocardial infarction are uncommon among individuals with lifelong very low plasma cholesterol levels.

Because fats are insoluble in water, cholesterol can not be transported in blood on its own.

The body’s solution to this problem is to bind cholesterol to certain proteins that function as transport vehicles carrying different types of fats such as cholesterol, triglycerides (TG) and phospholipids. These combinations of fats and protein are termed lipoproteins.

It is important to emphasize, that it is lipoprotein that interact with the arterial wall and initiate the cascade of events that leads to atherosclerosis.

Cholesterol is only one of many components of lipoproteins.  Therefore, measurements of total cholesterol provide little information about the lipoproteins that transport the bulk of cholesterol.

There is a strong and graded correlation between low density lipoprotein cholesterol (LDL-C) and the risk of CVD, both in women and men, although this has been debated by some investigators.

Measurements of the number of LDL-particles (LDL-P) appear more predictive of risk than measurements of the cholesterol mass within these particles or LDL-cholesterol (LDL-C).

Although LDL’s seem to be the most atherogenic particles, it has to remembered that VLDL and other apoB – containing lipoproteins may also contribute to atherosclerosis.

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Apolipoprotein B (apoB)

Lipoproteins are the particles that transport cholesterol and triglycerides in the blood stream.

Lipoproteins are comprised of proteins (apolipoproteins), phospholipids, triglycerides and cholesterol. The lipoproteins vary in the major lipoprotein present, and the relative contents of the different lipid components. ApoB is an important component of many of the most atherogenic lipoprotein particles.

ApoB occurs in 2 main forms, apoB 48 and apoB 100. ApoB 48 is synthesized mainly by the small intestine. ApoB 100 is the apolipoprotein found in lipoproteins synthesized by the liver. Therefore, from the viewpoint of atherosclerosis and cardiovascular risk, apoB100 is the important one. ApoB 48 is primarily found in chylomicrons.

ApoB 100 is found in chylomicrons, VLDL, IDL, LDL and LP(a) particles. All these particles are atherogenic. Each of these particles contains a single apoB molecule. Therefore, measurements of apoB represent the total burden of the main lipoprotein particles involved in the atherosclerotic process.

Usually, 85-90 percent of apoB represent LDL particles. Thus, apoB reflects particle concentration, similar to LDL-P. Although measurements of apoB are not widely available, the assay has been standardized and does not require a fasting sample.

Several studies have shown that apoB may be a better predictor of cardiovascular disease risk than LDL-C. Furthermore, it has been shown that apoB may be elevated despite normal or low concentrations of LDL-C. ApoB also appears to predict on-treatment risk, when LDL-C has been lowered by statin therapy. The INTERHEART study found that the apoB/apoA1 ratio is more effective at predicting heart attack risk, than either the apoB or apoA1 measure alone.

Apo B containing lipoproteins are the ones that are most likely to enter the wall of the arteries. They are capable of trafficking cholesterol into the artery wall, and if present in increased numbers they may be the main initiating factor in atherosclerosis. Retention of ApoB containing lipoprotein particles within the arterial wall is an essential part of the process.

Normal Range For ApoB

The normal range for apoB is 40-125 mg/dL.

Usually less than 100 mg/dL is considered desirable in low or intermediate risk individuals.

Less than 80 mg/dL is desirable in high risk individuals, such as those with cardiovascular disease or diabetes.

How to Lower ApoB

Many doctors will recommend the same general measures to lower apoB as they do for lowering LDL-C. Thus, reducing the amount of saturated fats and cholesterol is often recommended together with increased consumption of vegetables, fiber and mono-and polyunsaturated (omega-3) fatty acids.

Some studies have indicated that carbohydrate restriction may lower apoB, independent of whether the intake of saturated fat is low or high. LDL-C was not lowered by carbohydrate restriction in these studies, suggesting that diet may affect apoB and LDL-C differently.

Physical exercise has also been shown to lower apoB and positively affect the apoB/apoA1 ratio, but the effect on LDL-C appears to be much smaller.

ApoB levels can be reduced by cholesterol lowering drugs (statins).

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70 thoughts on “Apolipoprotein B (apoB)”

  1. Saturated fats have very little effect on cholesterol levels compared to other dietary factors. https://healthydietsandscience.blogspot.com/

    Interestingly, lower levels of LDL-C are associated with increased cancer risk. https://www.theheart.org/article/1375049.do If food elements (think omega-6 industrial seed oils) that lower LDL-C also increase cancer risk, lowering LDL-C in the wrong way might conceivably reduce the heart attack death rate by increasing cancer deaths. Another important consideration is evidence that higher LDL-C levels are associated with preservation of lean muscle mass. Hence, trying to lower LDL-C by exercising may be an exercise in futility. https://www.eurekalert.org/pub_releases/2011-05/tau-cn050511.php

    Then there’s this: https://perfecthealthdiet.com/wp/wp-content/uploads/2011/06/O-Primitivo-Cholesterol.jpg

    • Thanks David for these useful comments. By focusing so much on cholesterol in itself being harmful, we have become quite confused through the decades. This has sometimes lead to misunderstanding and unnecessary debates. Although the epidemiological studies indicate an association between cholesterol and cardiovascular risk, the data is confusing, not least when it comes to total mortality, where we have seen that those with the lowest cholesterol levels have high mortality. This is very well demonstrated in your last reference. Furthermore, the possible association between low cholesterol and cancer has never been really shut down as you also point out.

      There is really no reason to see cholesterol as a harmful substance. It is only when cholesterol, bound to atherogenic lipoproteins becomes trapped within the arterial wall, that it becomes a part of the pathophysiological process of atherosclerosis. Atherosclerosis does not occur in the absence of cholesterol. LDL is the most atherogenic particle and this lipoprotein contains cholesterol. That does not mean that cholesterol is bad. Similarily, atherosclerosis would not occur without the response of our immune system. Of course this does not mean that our immune system is bad. On the contrary, it is essential for life. Cholesterol that is bound to nonatherogenic particles, such as HDL is not associated with high cardiovascular risk, further supporting the fact that cholesterol in itself is not the problem

      Lipoproteins play an essential role for the initiaton and progression of atherosclerosis. Therefore it is very important for us to understand what regulates the production and clearance of atherogenic lipoprotein particles and how these mechanisims may be influenced. LDL-C is only a measure of the cholesterol mass within LDL-particles. Thus, LDL-C only indirectly reflects the atherogenic potential of LDL particles. ApoB and LDL-P on the other hand reflect the number of atherogenic particles, with no mention of cholesterol mass. Therefore apoB and LDL-P are better risk predictors than LDL-C.

    • Hi Zepp, Yes, I do follow Peter Attia´s blog.
      “Läser också LCHF magazinet varje gång jag besöker Sverige vilket är rätt ofta.”

  2. I was wondering if you address the role of Lp(a) and how to address having a very high value (mine is 425!). Thanks.

  3. After a car accident in 2008 I began having daily headaches and then migraines. Not one to want to be on medications, I decided to try the ketogenic diet hoping that would help.

    I have been following a ketogenic diet for the past year (more strictly at some point that others- but recently very good) and I have since taken myself off of my daily migraine medications!

    I have had my second blood test over the last year and although my general cholesterol numbers are good, my lipid panel for Apo B and LDL-P have gotten worse.

    My basics – 48 yo, good general health, pilates 3x wk, about 15 lbs overweight- but have lost 25 so far

    Numbers from 1st test to 2nd blood test.

    LDL-C from 131to 123
    HDL-C from 86 to 93

    with and overall of 215

    Triglicerides from 64 to 52

    but what is critical is –

    Apo B from 92 to 94 from bad to worse

    LDL-P 1395 to 1511 again bad to worse.

    The most specific information I have found has been on your site- thank you! But I am concerned as it was said that the ApoB and the LDL-P are more critical biomarkers for CVD.

    Should I be worried?? I want to continue with this lifestyle, but need to make sure I am staying healthy and safe in my diet choices and have not been able to find any local doctors ( I live in Los Angeles, CA ) who specialize in the ketogenic diet who aren’t specific to treating Epilepsy.

    Your insight is greatly appreciated!

    Susan

  4. Heart disease is not a product of too much cholesterol, but rather a lack thereof. Statins are the worse thing you can put in your body for a million different reasons. Most heart disease is a lack of sulfur or cholesterol sulfate (get more sun!). Donate blood if your blood viscosity is high a couple times a year, studies have show that those that do this have 75-80% less chance to suffer a heart attack. Drink lots of water and do this instead of taking a blood thinner. Blood thinners and Statins are the ‘norm’ must take with any cardiovascular event that your doctor tries to give you, both are bad. Asprin even worse! And when they try to give you a beta blocker or third medicine, tell him or her to go to hell, if you blood pressure is high it is to get the same amount of oxygen to your major orgains (brain, hello!) as it would had you had no issue or as a normal healthy person would get. Lowering it make sense, No or No?
    Get to the root cause. I will give anyone interested the perfect fix to any cardiovascular issue or any issue for that matter.
    1) Eat high quality organic diet, 65%fat, 25% Protein, and 10% carbs.
    2)Juice daily, vegetables mostly and limite fruit juices and fruit. Apple juice worse than a coke!
    3)Exercise daily, even if just walking 30 minutes a day to start.
    4) Get sunlight daily! Needed for vitamin D and more so Cholesterol Sulfate to transport cholesterol.
    5)Take suppliments (example: multi vitamin, Krill Oil, Niacin, B complex) At a minimum these.
    6)Walk barefoot on sand or grass often (grounding). Do not want to get into it here but search it.
    7)Keep fats healthy. Avacado, nuts, coconut oil or products, and yes eggs especially the yolk!
    I know you have all been told the yolk is bad and egg whites only is best…. WRONG! If you diet is in check and doing as outlined above, they are great if cooked right. Sorry you CANNOT scramble them, but rather sunny side up with yolk at room temperatur is the way you need to go. You see, heating up the yolk past flash points will cause the cholesterol to oxidize and we do not want that. So cook sunny side up and take off the pan as soon as you see the whites form 🙂
    How do I know all this? I had a stent in 2012 with 99 percent blockage and a 4 hour heart attack. I was put on a statin and cholesterol medicine. I made no changes the next two years, and continued not getting exercise, smoking, eating fast food and sweetened coffee drinks each morning at StarBucks. My weight got up to 300 lbs! I went in this year on March 12th with Angina pains the prior weeks getting worse. I could not even walk to the cardiologist without chest pains. He listened to my symptons, looked at my blood work (had high tryglicerides and LDL), proscribed me a beta blocker for my high blood pressure to take with me current statin and cholesterol medicine, and wanted to schedule me for another angiogram/angioplasty.
    I went home and said this cannot be the way. Next day I quit cold turkey smoking, eating fast food, and coffee’s and started walking (went on short term disability due to my numbers so bad the doctor made me). I did all the research I could over the next week, starting with Mercola.com and from there found Dr. Stenphanie Seneff and others. The result, I quite ‘all’ my medications and am doing what I outlined above. Lost 30lbs in the past month, can go 60 Minutes on an incline treadmeal, and take no medications. It works.
    I went in 30 days later with new blood work and a second opinion and they were shocked at my new levels and blood pressure (went from 160/93 to now 119/78 in 30 days). Imagine the look on my doctors face when I said “instead of going to fill the proscription that day for the Beta Blocker, I went home and stopped all my medications, stopped smoking and starting to eat a high fat diet”….
    You see, the current generation of doctors are not taught this stuff and it will take a generation or two to see the real problem and phase out the pharmacutecal companys and boycott the FDA, mostly owned by the Pharmas and Monsanto. I could go on a whole rant about GMO and Glyphosate currently in most all of our agrigulture and cattle, but not now. It is at the root of most all diseases onthe rise, espectially Autism and Alzheimers. I hope this info inspires someone else. God Bless

    • Paul, your story is inpsiring. It’s scary to take matters into one’s own hands but when you are faced with something like that, it only makes sense to do so. My cholesterol has always been high, due to hereditary factors, but it has been going up. My Apo B is high. My LIpo A is also high. And LDL-C High. But I have very good HDL. I always thought that was enough to protect me but now I’m not so sure. It seems hopeful that if I follow at least some of the nutrion/exercise guidelines it could get better. Thanks for your story.

    • Hello guys, I hope someone will be able to respond .. As I fell in the same situation as Paul Did, heart attack, 2 stents, and still have 4 plugged arteries… been on and off medications for the past 6 month, and doing a monthly blood test trying to monitor everything… Trying to fly to the USA to get the LDL Particle done, as we do not have it in Canada.

      But this is my latest results, and it;s kinda scary, as I am doing the Paleo / Ketogetnic Diet… Zero carbs for 4 month now

      LDL = 392
      HDL = 77.34
      TRIG= 86.80

      HS-CRP = 1%
      Apolipoprotein B = 235
      Lipoprotein A = 102

      Went down from 19% body fat, now at 12% but the numbers are still high..

      Any suggestions…

      • Maurice
        With this ApoB level your LDL-P will most likely be high as well. You would definitely want to see lower numbers in someone with coronary artery disease. Are you taking statins?

      • I was off for a while, doing testing back and forth, but I am back on it again.. to figure a way to control it better… I am taking Lipitor 10mg to support a bit, as if I take higher dosage I tend to get foggy…

      • your LDL rate is a bit scary, stop eating animal fats and eat lots of fish, avocado and olive oil. I’m just starting on this plan – going to eat fish tacos every day for starters, using olive oil. my ApoB is lower than yours but my MD wants to put me on statins.

      • I think one of the mistake I was doing, when I went full Keto .. I stopped all the carbs, lost all the weight felt great, but increased too much fat, 5 to7 spoons of coconut oil, plus I was consuming lots of the animal meat as well.. possibly that increased by apoB to increase dramatically. for the past 3 weeks none of that stuff and a new blood test is getting done soon. so I hope it has dropped normal range…

  5. Hey Doc can you provide a citation for this? “Usually, 85-90 percent of apoB represent LDL particles. Thus, apoB reflects particle concentration, similar to LDL-P.” Thx!

  6. I have been watching my cholesterol for the last 10 years of so because my father died of a heart attack age 58. My numbers have been reletivly good, always very high HDL (1.8-1.9 mmol) and total cholesterol around 6 mmol. I also had a calcium score a few months ago and it came out with score 0. All good, I am 55 years now and it seems that I may live longer than my father. The last test i took was APO lipo proteins, hsCPR, lp(a) and a direct LDL measurement. And the results

    Direct LDL 123 mg/dL (3.2 mmol)

    APO A1 240 mg/dL ( lab reference 140 -240)

    APO B 23 mg/dL ( lab reference 20 -65 )

    Lp (a) 12.6 mg/dL

    hsCPR 0.1 mg/L

    My problem is this really is too good to be true. In these tests I have extremely low APO B and very high APO A1.

    I did this test when I was in Peru and the lab seem to be a major clinical lab in Peru.

    https://www.labroe.com/roe/default.aspx

    It´s just that the results are almost to good to be true. I have always had a very high HDL and as such i can belive that my APO A1 is high. But that high……

    And about the APO B level, is it possible with such low values when my LDL is not really very low

    I have been eating low carb for the last 10 years or so

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