Anyone who's spent much time around me knows I eat my share of - and this is by no means the unabridged list - beef, whole eggs, butter, organ meats (specifically liver), etc. I am relatively "fit," especially by American standards, so I tend to field a lot of comments about the fat and specifically the cholesterol content of what I am eating. I have absolutely no qualms about answering questions from the legitimately interested, but occasionally the comments display with objection or even horror. Usually in those cases I'll just shrug it off or say "well, this is what I like." And that's true - I do like those things. But very often the judgment comes from the mouth of someone who A.) knows considerably less than I on the subject of nutrition in general, B.) is shapelier than I and C.) actually has a lower total serum cholesterol level than I (an astonishing 302 mg/dl!). Now, I've got no real reason to get on the defensive and I am hardly worried about my lipid panel, but I have spent a lot of time and effort to put my mind and body in its current state so naturally it's a bit bothersome to face animosity from some wet-behind-the ears chubber. Pardon the insensitivity, but really, if you don't know what you're talking about, why even comment? (Shit, I hope about 97% of my Facebook friends read this and take that sentence to heart). I'm very opinionated by nature and I'm actually a decent living-room Jeopardy player, but you can be fairly certain to count me out of conversations regarding things unfamiliar, such as Middle Eastern history, investment banking, and burning dog poo and the human response...Okay, so maybe I know a thing or two about that last one.
Mad cholesterol, yo.
Cholesterol serves many important functions in the body. The waxy steroid fat manufactured by every mammalian cell helps cells maintain proper temperature, permeability, and fluidity. Humans and other vertibrates produce most cholesterol in the liver, which is then used to synthesize a number of critical hormones and perform other various tasks throughout the body. The average person produces about 1 gram per day and houses about 35 grams total. For whatever reason, American guidelines recommend limiting intake to 300mg/day (less than the amount in 2 egg yolks and 30% of what is ALREADY VITAL to synthesize). In addition, most cholesterol in animal-based food products has reacted with a fatty acid to form an ester. Esterified cholesterol is very poorly absorbed. Even further, the body reduces it's cholesterol synthesis to compensate for any that does get absorbed from food. Lesson #1: eat your yolks.
The heart of the issue here (see what I did there?!) is that cholesterol isn't actually a cause of heart disease; people with "poor lipid panels" are just displaying an antimicrobial defense symptom for some other underlying cause. I've found doctors tend to like writing prescriptions treat symptoms; I like the analogy of buying a washing machine for a bedwetter. Kind of silly. The base lipid panel - total cholesterol, LDL-C, HDL-C, triglycerides - can give you some idea of potential disease risk, but there are definitely some flaws in that methodology as well.
This is a somewhat crude and grossly simplified analogy, but I think it really helps with perspective: think of your blood vessels as rivers. The lipoproteins colloquially known as HDL and LDL are the boats in the rivers, while cholesterol and triglycerides (which are the circulating fat energy source) are cargo that are transported on the boats from the liver (shipping center) to various cells or back to the liver for excretion or re-utilization. Free radicals are like pirates that damage (oxidize) the boats and cargo, and anti-oxidants are protection officers against the pirates. The lipid panel measures the total cargo, but the main main factor that causes heart disease is the total amount of (oxidative) damage done by pirates, which is influenced by the number of boats, pirates, and protection officers (basic probability) and the size of those boats. Big boats are "intimidating" in this example. HDL are the biggest boats, and are often considered "good cholesterol" because they can use some of their deck space to bring damaged cargo back to the liver for fixin'. There are various levels of LDL particle size - which is strongly correlated with triglyceride number due to storage space - and that matters because the smaller ones are the most prone to damage. Particle size is not represented in your LDL-C number.
A heavily magnified view of the inside of your carotid artery.
Still following? That got a little more abstract than I anticipated, but the premise should still be pretty clear. Now, a main factor in both LDL particle count and particle size is how well your various cells can utilize the cholesterol on them. All cells have LDL and fat receptors that signal for the boats to stop and unload the cholesterol and triglycerides so that they can go to work within the cell. But those signals can malfunction due to lifestyle or genetic factors (metabolic syndrome and insulin resistance - high-carbers will use circulating glucose before triglycerides, thyroid damage, infection/inflammation, mutation of specific gene coding, etc.), and when that occurs the cargo remains on the boat and continues circulating in your blood rivers, vulnerable to pirate attack. Since there's more cargo being produced than is used, the liver needs to produce more boats to carry it. The size of the new boats is based largely on what dietary feedback. There are factors that increase the number of pirates too: stress - including smoking, too much exercise, too little sleep, environmental toxins, etc; poor intake of anti-oxidant rich foods (remember the protection officers); high intake of polyunsaturated fats (in particular, omega-6 linoleic acid) - which are very unstable and as a result often form free radicals during metabolism. Are we getting the picture? Raise your hand if you're asleep.
In summary, cholesterol in you blood is a symptom that can predict your risk of heart disease, but only eating and sleeping better, managing stress, and exercising a proper amount treat the underlying issues causing the symptom. Those recommendations are nothing new. Personally I try to do those things as best I can. But surely that amount of cholesterol in my blood requires lots of boats, so why am I not worried? Let's look at the recommended levels and compare hypothetical person A's results against my own (B) numbers from March of 2012 (note that the addition will be close but not exact, because the numbers are actually calculated based on other feedback from the blood test - yet another flaw):
Total cholesterol: A - 192, B - 301
LDL - C: A - 144, B - 189
HDL - C: A - 47, B - 98
Trigs: A - 148, B - 45
A doctor would likely tell person A that her numbers look pretty good, but her LDL-C is borderline high; "dial back on cholesterol and saturated fat" and that she should be just fine. However, she has a low percentage of total cargo on big HDL boats, and a not insignificant number of triglycerides taking up space, ultimately requiring more LDL boats to carry the cholesterol. Based on these numbers one could surmise she may have some minor LDL receptor defect and she has some issues clearing triglycerides (perhaps she eats a decent amount of carbohydrates). Her VAP test (test for LDL particle size - NOT standard, you'll pay extra for this one) would likely reveal a lot of smaller LDL boats.
In contrast, I have a VERY high TC, LDL-C, and HDL-C, while triglycerides are EXTREMELY low. I suppose this could indicate some LDL receptor impairment, but is much more likely a result of genetics and lifestyle. For the record, research has shown that high intake of certain saturated fatty acids can increase HDL-C independently or both HDL-C and LDL-C in certain individuals, but neither situation has any correlation with actual heart disease risk. My results show a good portion of my total cargo is on relatively safe HDL boats, and even though there is a lot of cholesterol on the LDL boats, there aren't many triglycerides on them (why? because I used them for fuel!). High HDL-C and low triglycerides usually indicates mostly large LDL particles, which we discussed are less prone to oxidative damage. All of this means the relatively high LDL-C can still fit on less total LDL boats!
So whose risk is higher? It's really impossible to tell based on the standard lipid panel, but somehow, a high TC and LDL-C is taboo enough that my doctor recommended I start taking statins at the ripe old age of 25. He went to medical school and I did not, but before I went and obliged to taking something unnecessary (and potentially harmful!), I made sure I did my due diligence and ended up learning all of this shit about boats. A little responsibility to take a deeper look made my numbers look a lot less scary. The bottom line is, you guys, that you have to take charge of your own fate. If you care about something, do your own research and get informed. If you don't, leave it alone and stop commenting about my intake of red meat.
A doctor would likely tell person A that her numbers look pretty good, but her LDL-C is borderline high; "dial back on cholesterol and saturated fat" and that she should be just fine. However, she has a low percentage of total cargo on big HDL boats, and a not insignificant number of triglycerides taking up space, ultimately requiring more LDL boats to carry the cholesterol. Based on these numbers one could surmise she may have some minor LDL receptor defect and she has some issues clearing triglycerides (perhaps she eats a decent amount of carbohydrates). Her VAP test (test for LDL particle size - NOT standard, you'll pay extra for this one) would likely reveal a lot of smaller LDL boats.
In contrast, I have a VERY high TC, LDL-C, and HDL-C, while triglycerides are EXTREMELY low. I suppose this could indicate some LDL receptor impairment, but is much more likely a result of genetics and lifestyle. For the record, research has shown that high intake of certain saturated fatty acids can increase HDL-C independently or both HDL-C and LDL-C in certain individuals, but neither situation has any correlation with actual heart disease risk. My results show a good portion of my total cargo is on relatively safe HDL boats, and even though there is a lot of cholesterol on the LDL boats, there aren't many triglycerides on them (why? because I used them for fuel!). High HDL-C and low triglycerides usually indicates mostly large LDL particles, which we discussed are less prone to oxidative damage. All of this means the relatively high LDL-C can still fit on less total LDL boats!
So whose risk is higher? It's really impossible to tell based on the standard lipid panel, but somehow, a high TC and LDL-C is taboo enough that my doctor recommended I start taking statins at the ripe old age of 25. He went to medical school and I did not, but before I went and obliged to taking something unnecessary (and potentially harmful!), I made sure I did my due diligence and ended up learning all of this shit about boats. A little responsibility to take a deeper look made my numbers look a lot less scary. The bottom line is, you guys, that you have to take charge of your own fate. If you care about something, do your own research and get informed. If you don't, leave it alone and stop commenting about my intake of red meat.
Now go and lift some heavy shit!