Thursday, March 19, 2009

Picture Cholesterol as an Antioxidant*

Greetings friends,

I've had a wonderful break and am now ready to talk about cholesterol. In gist—please don't get a heart-attack over this—all you've heard about cholesterol through mainstream media is pretty much very wrong. Cholesterol does not cause heart attacks or indicate a greater risk for cardiovascular disease. That's almost the whole story, but to be fair, I'll offer some more explanation. Let's start with what cholesterol actually is and what it does in the body.

Cholesterol is a waxy, fatty substance that is technically something between a steroid and alcohol and is therefore designated as a sterol. It is manufactured primarily by our liver though the intestines, adrenal glands and reproductive organs synthesize some of it, too. As you can figure now, considering our body actually makes its own cholesterol, it is a highly important substance. Cholesterol performs a host of vital functions that amongst others include, building and maintaining cell membranes (the average human has 100 trillion cells), ensuring the semi-permeability of cell membranes so that the right substances can cross into the cell, manufacturing hormones, and it also functions as an inter-cellular mode of transport for other substances. If you remember from the last blog, 60% of our brains are made of fat. Well, cholesterol's role in that is to coat nerve fibers (myelin sheath) to ensure the speed of nerve impulse conduction that we enjoy. And all of these are just some of the functions. Finally, if your cholesterol is too low, you die.

Knowing this, you may wonder why cholesterol is vilified so much as the demon that will give you cardiovascular disease and clog your arteries. Or even better, you may not be convinced by my off-hand list, in which case I highly encourage you to look up all of these functions I've listed (and get back to me if you find me to be wrong). Because I don't like to deal in conspiracy theories, the explanation for cholesterol's bad reputation that I'll offer hinges on a severe and gross misunderstanding. Here is an analogy I like which original source you can find here: Imagine you're walking down the street and you see that a fire has burned a house down and that there is a fire-truck next to the site. A week later you come upon a different location, but it's the same sight, namely a smoldering ruin and firetrucks next to it. And a few days later, the same thing. So you conclude that firetrucks are causing fires!

You don't need to be a mathematician to see the flaw in logic here. It's a cause attributed to a correlation. It's the first thing you learn not to do when you begin studying any science, but because we don't live in an ideal world there actually is some bad science out there, and some of it concerns the role of cholesterol in disease. So what would you say if I told you that cholesterol is around when heart-attacks happen because it was trying to fix the inflamed cells? In other words, it was trying to do the things it does (repair and maintain cells etc.) and protect your body. Well, by now we've realized that this alternate explanation is a very likely scenario, but the reason it doesn't reach mainstream America is because pharmaceutical companies and certain food manufacturers spend billions on advertising for cholesterol lowering drugs and foods, while, on the other hand, scientists finding out that the medical establishment is perpetuating an error depend on grants that don't leave them much extra money to buy some prime-time commercial spots. But if you'd like to spread the news and possibly inform some loved ones that they might be potentially harming themselves because they're on cholesterol lowering medication, this is a very balanced, down-to-earth, comprehensive video explaining the implications of cholesterol.

Furthermore, the notion that LDL is “bad” cholesterol and HDL is “good” cholesterol is simply false. I'm even tempted to say that it's absolute nonsense. If you look at the acronyms more closely you will find that LDL stands for “Low Density Lipo-Protein” and HDL stands for “High Density Lipo-Protein.” As the names clearly tell you, these are proteins. LDL and HDL aren't even cholesterol. Cholesterol, as explained earlier, is a fatty substance called a sterol, while LDL and HDL are proteins—two completely different molecules. Cholesterol is just cholesterol and because it's not water-soluble it needs the help of LDL and HDL to be transported to all the cells where it performs its vital functions. LDL transports cholesterol from the liver to the cells, and HDL transports the cholesterol that has been “used up” by the cells back to the liver where it either gets recycled or discarded. (The fact that our body actually recycles cholesterol is another indicator of just how important of a substance it is).

If cholesterol is regarded as the villain, then it makes sense why LDL—the protein that brings cholesterol to the cells—got the bad rep. Although, the human body is immensely complex and placing the blame for major disease on a single protein is ridiculously over-simplified, there is one instance where LDL causes harm. In its normal state LDL is an essential transporter for cholesterol, but when it becomes damaged LDL actually is a risk factor contributing to inflammation and potential heart disease. If you recall from my last blog, damaged molecules are called "oxidized." So when there is a greater occurrence of oxidized LDL, there is a greater risk for heart disease. To keep LDL oxidation in check, your antioxidant intake should be high. (Amongst other sources, they can be obtained in fresh fruits and vegetables. For greatest protection and overall health, people should eat a wide variety of fruits and vegetables of all colors in order to obtain many types of antioxidants [and of course nutrients] available.)

Several studies have shown that high cholesterol levels are not indicative of heart disease, but rather that damaged LDL together with inflammation factors is a far more accurate predictor of disease. If you think about it, cholesterol is a substance your body makes itself and transports where it wants it. If you have elevated cholesterol, it's likely there “on purpose” so to speak. For a great in-depth explanation of the LDL vs. HDL misconception, here is a comprehensive article with about a hundred sources illustrating the role of oxidized LDL in heart disease as well as the issues involved with cholesterol-lowering drugs.

Finally, eating cholesterol-rich foods will NOT impact your cholesterol levels. I hope that understanding what I've explained to you so far will make this statement only sound logical. But to reiterate; it is your body that makes and uses cholesterol as it sees fit. If you eat more cholesterol, your body makes less, if you eat less, your body makes more. So eating eggs, unless you're allergic, is a great idea. Eggs, that is egg yolks, are a great source of nutrients**.

There, however, are studies that indicate a correlation of elevated cholesterol and trans-fat and saturated fat consumption. As explained in the previous blog, trans fats are oxidized fats and are loaded with free radicals (particles that wreak havoc on your cells and cause damage that eventually leads to heart disease). So cholesterol likely goes up to fix the damage. As for saturated fats causing elevated cholesterol levels, the only thing I have read about is that eating red meats is very hard on your body to digest, and cholesterol plays a function in bile creation which digests fats for absorption. Red meats are the meats highest in saturated fat content (poultry has up to 70% unsaturated fat) which doesn't mean you shouldn't eat them, it just means you shouldn't eat them all the time.

All in all I hope I've explained that cholesterol is not the demon that will hit you with a heart-attack. In general, I find that whenever a single factor is identified as the ultimate villain or the ultimate hero, the information is just plain incomplete or sometimes, as in this case, completely wrong. So now that cholesterol is off the hook, you may be wondering what actually does increase your risk for coronary heart disease and the answer is that one of the highest risk factors leading to heart disease as well as diabetes is sugar. But more about that next Friday.

Till then,

"As I see it, every day you do one of two things: build health or produce disease in yourself."--Adelle Davis


*Antioxidants are molecules that keep other molecules from getting oxidized/damaged and can thereby treat and/or prevent disease.

**If you like eggs, I highly encourage you to buy free-range, organic eggs because they have far more nutrients, but I'll likely talk about the difference between organic vs. conventional foods in an upcoming blog.

2 comments:

  1. Great post, Tina. Everything is illuminated : )
    Thanks for sharing.

    Jason

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  2. Hey Jason!
    I didn't even know you had an account on here. Glad you liked the post. =)

    ReplyDelete