Marks Daily Apple
Serving up health and fitness insights (daily, of course) with a side of irreverence.
21 Dec

How to Interpret Cholesterol Test Results

Before we get into the big job of interpreting cholesterol numbers, let’s review what cholesterol actually is.

Cholesterol is cholesterol: a waxy steroid of fat that serves as an essential structural component of cellular membranes and in the production of steroid hormones, vitamin D, and bile acids. Contrary to what the terminology indicates, there’s actually only one “type” of cholesterol in the human body, and it’s called, quite simply, cholesterol. What we think of when we use the word “cholesterol” is actually a lipoprotein – a fatty conglomerate of protein and lipids that delivers cholesterol and fat and fat-soluble nutrients to different parts of the body. It’s not just free cholesterol floating around in your blood; it’s cholesterol bound up by lipoproteins.

So LDL, HDL, VLDL, all those (in)famous measurements we get at the doctor’s office are just different types of lipoproteins. They’re not actually cholesterol. I discussed this briefly a couple years back, and there’s always Griff’s big primer in the forum, so take the time to go check out both. And also take a peak at The Definitive Guide to Cholesterol for review.

Okay, let’s talk about the most commonly bandied-about cholesterol numbers: LDL-C and HDL-C. What do they really mean? What are they actually measuring?

To understand what these numbers mean, let’s play the freeway analogy game. Both LDL-C and HDL-C, the standard, basic readings you get from the lab, do not reflect the number of LDL or HDL particles – the number of lipoproteins – in your serum. Instead, they reflect the total amount of cholesterol contained in your LDL and HDL particles. Hence, the “C” in LDL/HDL-C, which stands for “cholesterol.” Measuring the LDL/HDL-C  and then making potentially life-changing health decisions based on the number is like counting the number of people riding in vehicles on a freeway to determine the severity of traffic. It’s data, and it might give you a rough approximation of the situation, but it’s not as useful as actually counting the number of vehicles. A reading of 100 could mean you’re dealing with a hundred compact cars, each carrying a single driver, or it could mean you’ve got four buses carrying 25 passengers each. Or it could be a couple buses and the rest cars. You simply don’t know how bad (or good) traffic is until you get a direct measurement of LDL and HDL particle number.

Say you go ahead and get those particle numbers directly measured. You’re still limited, because that is just a single datapoint from a specific time in your life/day/week. Analogies are fun and helpful, I think, so let’s take this traffic and freeway stuff further. To get an accurate idea of traffic, you need constant updates, right? Imagine you counted the number of cars on the freeway at 12:05 on a Saturday afternoon four weeks ago. That’s great, but what does it tell you about traffic at 5 PM on a Thursday? Even though it’s the same stretch of asphalt/artery, we can’t divine much at all from that single measurement. You need more data points. That traffic fluctuates wildly is entirely uncontroversial. Any southern Californian could tell you that. But did you know that LDL, HDL, and total cholesterol readings in the same person can fluctuate just as wildly, oftentimes enough to move that person from “desirable” to “high risk” and back to “desirable” lipid status without any nutritional or lifestyle changes in the span of a few mere weeks?

In biology, a single snapshot rarely, if ever, tells the whole story. Who woulda known?

But just because the standard cholesterol test is but a snapshot of a dynamic system in flux doesn’t negate the potential usefulness of getting your cholesterol checked. As much as Conventional Wisdom has gotten things wrong when it comes to cholesterol and heart disease, the two do have a relationship together. There is a connection; contrary to what the AHA might think, we just don’t have it ironed out yet. In my opinion, the most persuasive hypothesis about the real causes of atherosclerosis and heart disease comes from Chris Masterjohn and is highlighted in his recent AHS talk, “Heart Disease and Molecular Degeneration,” and on his blog. It’s a synthesis of the two prevailing notions regarding cholesterol and heart disease – the one which says elevated blood cholesterol plays no causal role in heart disease and the one which says elevated blood cholesterol is the primary cause of heart disease – and it goes something like this:

LDL receptors normally “receive” LDL particles and remove them from circulation so that they can deliver nutrients and cholesterol to cells, and fulfill their normal roles in the body.

If LDL receptor activity is downregulated, LDL particles clear more slowly from and spend more time in the blood. Particles accumulate.

When LDL particles hang out in the blood for longer stretches of time, their fragile polyunsaturated fatty membranes are exposed to more oxidative forces, like inflammation, and their limited store of protective antioxidants can deplete.

When this happens, the LDL particles oxidize.

Once oxidized, LDL particles are taken up by the endothelium – a layer of cells that lines the inside of blood vessels – to form atherosclerotic plaque so they don’t damage the blood vessel. This sounds bad (and is), but it’s preferable to acutely damaging the blood vessels right away.

So it’s the oxidized LDL that gets taken up into the endothelium and precipitates the formation of atherosclerotic plaque, rather than regular LDL. OxLDL, poor receptor activity, and inflammation are the problems. But since measuring oxidized LDL in serum is difficult (oxidized LDL gets taken up out of serum and into the endothelium rather quickly) and expensive, we need other, more realistic, more obtainable methods. We need to work with what we’ve got. It would be great if a doctor could quickly order up an “LDL receptor activity” test, but I don’t see that happening anytime soon.

Enter the various lipid panels.

First up is your basic lipid panel, the standard test the average doctor is going to order for a patient. If you go this route, you’ll typically get four measurements: total cholesterol (TC); high density lipoprotein cholesterol (HDL-C); low density lipoprotein cholesterol (LDL-C); and triglycerides.

Total cholesterol

What they say: Get that TC below 200, or else (you’ll have a heart attack or you’ll have to pay a higher health insurance premium, if we take you on at all).

My take: Mostly meaningless. Even though the epidemiological evidence suggests a TC between 200 and 240 mg/dl is best for all-cause mortality, we can’t hang our hats on it. First off, total cholesterol is limited because it’s only telling us the amount of cholesterol contained in all our lipoproteins without saying anything about what kind of lipoproteins we have or how many there are. Second, total cholesterol is limited because it’s determined by a bizarre formula – HDL-C+LDL-C+(Triglycerides/5) – that reduces various types of blood lipids, each with a different role in the body and a unique impact on our risk for illness, to mere numbers. Someone with low HDL and high triglycerides could easily have the same TC as someone with high HDL and low triglycerides, so long as the numbers work out. Whether it’s being used to predict wellness or disease, total cholesterol by itself is mostly meaningless.

HDL-C

What they say: “Good” cholesterol. It’s the “garbage truck” that cleans up “excessive” cholesterol and fat from tissues, so the higher the better! Though men and women should strive for levels exceeding 60 mg/dl, above 40 is acceptable for the former and above 50 is acceptable for the latter.

My take: Higher HDL-Cs correlate strongly with better cardiovascular health. No real argument here. Higher HDLs are desirable. Just remember, it’s only a snapshot of a glimpse into the cholesterol content of your HDL particles. Among most groups tested, the TC:HDL ratio is actually a strong indicator of heart disease risk, with higher ratios corresponding to higher risks. Note, though, that no Primal Blueprint adherents were among the groups analyzed, ever.

LDL-C

What they say: Get it as low as humanly possible! I want that low density lipoprotein so low as to be nearly nonexistent. Your body obviously hates you; otherwise, it wouldn’t be producing a potently toxic substance and sending it directly into your endothelial cells to form atherosclerotic plaque! Of course, we’re not actually measuring the number of low density lipoproteins, just the amount of cholesterol contained in them, but still!

My take: While a high LDL-C may indicate a problem, remember that LDL-C only indicates the total amount of cholesterol in your LDL particles. You could easily have a few large particles (good) or a bunch of smaller, denser ones (bad, might indicate poor LDL receptor activity and an LDL that likes to hang out in the blood), but LDL-C alone isn’t enough to know. It’s also just a moment in time, whereas what you’re interested in is the trend. If the trend indicates a steady rise in LDL-C, however, that could hint at poorer LDL clearance and lower LDL receptor activity (and greater susceptibility to oxidation).

Triglycerides

What they say: Lower would be better, sure, but you really gotta do something about that LDL! Anything less than 150 mg/dl is fine.

My take: High triglycerides correlate strongly with low HDL and smaller, denser LDL. High triglycerides, then, could indicate more oxidized (or oxidizable) LDL. The triglycerides of most Primal eaters, especially those on the lower carb side of things, usually hover well below 100 mg/dl. Triglycerides come packaged in VLDL, or very low density lipoproteins (which are calculated by dividing your triglyceride count by 5).

So, what can we learn from a standard lipid test? Not much, actually. We can learn from standard lipid tests, however. If we take a series of regular ol’ lipid measurements, preferably one pre- and several peri-Primal, we can get an idea of our metabolic health. Look for:

  1. Trends – Are your triglycerides going down over time? That’s great. Is your HDL trending up? Also good.
  2. Normal fluctuations – Your numbers can jump around 20-30 points in either direction between readings without it necessarily meaning anything.
  3. TC:HDL-C ratioLower is better and indicates fewer LDL particles.
  4. Triglyceride:HDL-C ratioLower is better and indicates larger LDL (and, usually, fewer) particles. Ideally, this will be close to 1 or lower; one study (PDF) found that 1.33 was the cut off.

If you’re going to get your cholesterol tested, and the basic labs just aren’t cutting it, you might as well go for one of the premium lab tests: the NMR LipoProfile or maybe the VAP. Rather than rely on indirect estimates and formulas, NMR and VAP directly measure the  size of your lipoproteins. I find NMR to be far more useful, because in addition to measuring particle size, it measures particle count (whereas VAP only estimates the count).

But you probably have holiday shopping to do, and I don’t want to drone on for too long, so I’ll leave it at that for now. Next week, I’ll pick up where I left off and get into what you can expect from NMR and VAP testing, including the downsides and the advantages. After that, I’ll go into some strategies for improving your numbers – or, rather, improving your health which in turn should improve your numbers.

You want comments? We got comments:

Imagine you’re George Clooney. Take a moment to admire your grooming and wit. Okay, now imagine someone walks up to you and asks, “What’s your name?” You say, “I’m George Clooney.” Or maybe you say, “I’m the Clooninator!” You don’t say “I’m George of George Clooney Sells Movies Blog” and you certainly don’t say, “I’m Clooney Weight Loss Plan”. So while spam is technically meat, it ain’t anywhere near Primal. Please nickname yourself something your friends would call you.

  1. I am not saying they take the place of statins, but Red Yeast Rice and Plant Sterols are showing some very good results in lowering cholesterol for some people. I’d suggest looking into these products n iherb or something if you need to lower cholesterol. Worth researching, that’s for sure.

    We need saturated fat just not a lot of it. Every medical study on the planet shows we need to eat a low saturated fat diet. The SAD is high in saturated fat and calories. A burger has extremely high fat content. It’s not because of grains. Your grandparents probably ate white rice and white flour and potatoes growing up all their lives every day and I bet they were damn skinny back then. The foundation will always be how many calories you eat. Calories in vs. Calories out is not a myth! Cutting out carbs you are eliminating a lot of calories throughout the day. It isn’t 100% but calories is the core.

    You see Ryan Reynold’s body? Brad Pitt Fight Club days? They ate grains. They weren’t primal. They didn’t have stomach bleeding out into their stools, and were;t rolling over in digestive discomfort all day. Grains may or may not be for you, but come on, let’s be realistic here. Medical science distorts the truth to sell drugs, but they aren’t totally off.

    Jeremy wrote on December 29th, 2011
  2. Jeremy reminds me of an overly-opinionated middle schooler with a fundamentalist upbringing arguing with a developmental psychologist who researches adolescents that sex ed should focus on abstinence only curriculum because some people get stds or pregnant after honest sex ed curriculum.

    Diabetes is now ravaging Asia as high carb and transfat junk is unleashed on these new consumers by the transnationals.

    Jason wrote on December 29th, 2011
  3. Obviously whole grains like brown rice and quinoa are way better than refined ones like white rice or white flour, but my point was healthy and thin people have been eating grains for a very long time without problems, so to chalk them all up as unnecessary or the root to all evil or even the sole reason why people are fat, seems unjustified. Go as what your grandparents ate when they were growing up.

    My example with Asia was referring to the traditional Asian diets wiseguy, veggies meat and white rice, noodles and fruit, not modern additions such as KFC or McDonalds and potato chips that seem to be infiltrating like mad there.

    The intelligent people, who aren’t bound by “Primal” Dogma will understand the point I was making. Those who are hell bent on upholding their belief system will get angry and insult me.

    Either way, Mark sells his products, which is the whole point of this site really.

    Jeremy wrote on December 30th, 2011
  4. I meant “Go ask what your grandparents ate when they were growing up, to see the all grains are evil scare is nonsense.”

    What about the health benefits of fiber?

    Jeremy wrote on December 30th, 2011
  5. If there is anything to be taken away from this website, I would think it would be that PROCESSED FOODS are probably what has caused an increase in obesity. The chemicals inside the foods we eat today (which are VERY diffrent from what our grandparents ate) are probably messing with our insides in a way that isn’t completely beneficial for us.

    I don’t think anyone should be so hypnotized by one idea – whether diet, religion, politics, or brand name – that it causes anything against it to not even be worth talking about. However, I would say just about all of us have tried the “eat whatever we want when we feel we want it” diet, and had less than stellar results. Seeing as we’ve tried an alternative, it seems worth it to me to try this primal one.

    Chris wrote on December 30th, 2011
  6. After completing a PhD in exercise physiology and teaching it for years, my research is helping me to ‘unlearn’ half-truths that we’ve been taught for years (even in Universities).

    You’ve done a great job of explaining these complex processes in a very simple way Mark.

    Isaac wrote on January 1st, 2012
  7. After 6+ months on a low-fat, liquid protein diet my cholesterol numbers dropped from 223 to 201 with corresponding changes in HDL, LDL and triglycerides.

    After 5 months on Paleo my cholesterol numbers rose from 201 to 225 with corresponding changes in HDL, LDL and triglycerides.

    When I see my cardiologist on Monday I expect to be chided and encourage to take statins, to which I am overly sensitive, e.g. severe & crippling muscle pain and weakness. I don’t view statins as an option, so what shall I do instead?

    Background: my grandmother died of a massive heart attach @ age 51. My mother had quad bypass surgery two years ago due to four clogged arteries. Obviously, my goal is to avoid their fates. Please help. Thanks!

    Lorelai wrote on March 3rd, 2012
  8. Anyone care to comment on these numbers? I took a wellness screen January of 2011 through my employer. At the time of the screen I was less than a year out of college and had a terrible diet. Key points: I averaged around 6-8 beers per day, fairly SAD – lots of processed foods, decent amount of sugar. 6’1″ 210lbs. HDL = 39, LDL = 145, Tri = 164

    Around May I learned about LC, adopted in June essentially as Atkins. Slowly started finding Paleo/Primal and adopting that lifestyle. Completely cut bread & grains out, still had some dairy in the form of cheese and occasional ice cream. I’ve probably had 10 beers since Thanksgiving and now drink wine, mostly red, and not to excess like I did with beer. My meals are all homemade, I get local meats and veggies, I use A LOT of Kerrygold butter, and I’ve added white rice and some potato back into my diet the last few months as I’ve increased my workout intensity. Today I’m 6’1″ 165 lbs …Took another wellness screen 3 weeks ago and…drumroll…
    HDL = 41, LDL = 127, Tri = 191 …WHAT?!?! FYI, I was on an 11 hour fast at the time of testing.

    I’m confused and concerned at this point and once I finish this post am ordering an NMR test and will be taking that ASAP. I honestly am shocked at my Triglycerides and actually quite worried.

    Chirs K wrote on March 8th, 2012
    • Just read the follow-up to this post. Maybe I won’t go for an advanced test. Now I just don’t know what to do…

      Chirs K wrote on March 8th, 2012
  9. Don’t mean to spam but I thought of a little more info that might be relevant. The last 4 months or so I’ve been intermittent fasting. My first meal is lunch around 11:30 and then depending on how hungry I am when I get home I may eat as early as 5 or as late as 8 or 9.

    This is quite frustrating, I’ve really prided myself that, with the exception of occasional ice cream, I essentially removed sugar from my diet quite abruptly. If you thought I drank too much beer I’d love to hear your comments on my Oreo addiction.

    Trying to give an accurate timeline of things I’m realizing that I’ve made quite a dramatic change, multiple actually, in my lifestyle in just 9 months. Maybe I should give it another 3 months or so and get another standard lipid profile. Maybe my body has never really adjusted to anything since I’m constantly tweaking things. Still, Trigs at 191 is ridiculous for a moderate carb paleo eater.

    For the time being it looks like ice cream and I will be parting ways :(

    Chirs K wrote on March 8th, 2012
  10. had a blood test,and under the word Lipid was this comment CHOL/HDL RSK 2.9 L (3.8 – 6.9) I am asuming this mean my good cholesterol is low,Does anyone see it that way? Thanks, John

    John wrote on March 15th, 2012
  11. Hi Guys,
    Could someone please help me understand my numbers? Do I need further blood work due to my present numbers, and if so what am I looking out for? I’m a 37 yr old male, 5.8, 7.5% BF, 160lbs, 29-30 waist size, exercise regularly. Been on a paleo type diet for about a year now. Very low carb, less than 100g per day. I’m gonna give you all my numbers from before I switched from a high grain high protein low fat diet to the paleo type diet with around 9-12 ounces of animal protein per day, I switch my fats through the day, roughly one TBsp of olive oil, 1 tbsp of walnut oil for lunch, I cook all my proteins in either raw butter or coconut oil, I may have one ounce of raw almonds or 1 tbsp of almond butter raw or 1 scoop of coconut butter for a snack each day. 2 whole organic eggs per day. Lots of salads and 3 servings of steamed or sauteed greens per day. All I drink is mineral water. Please help me understand my numbers!

    High Grain High Pro/low fat diet #’s

    Total=200
    HDL=64
    LDL=99
    Trig’s ?

    6 months into paleo diet

    Total=237
    HDL=72
    LDL=122
    Trig’s=30

    12 months on Paleo diet

    Total=270
    HDL=79
    LDL=174
    Trigs=26

    Thanks for your time!
    Adam

    Adam wrote on May 26th, 2012

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