The Straight Dope on Cholesterol: 10 Things You Need to Know – Part 1

This is a guest post by Peter Attia and is a summary based on a 10-part series of the same name that you can find at The Eating Academy.   To put this summary post and, more importantly, this 10-part series in perspective, let’s examine one of the most pervasive pieces of dietary advice given to people worldwide: “Eating foods that contain any cholesterol above 0 mg is unhealthy.” – T. Colin Campbell, PhD, author of The China Study. No summary of this length can begin to fully address a topic as comprehensive as cholesterol metabolism and the pathogenesis of atherosclerosis. In fact, those of us who challenge conventional wisdom often find ourselves needing to do exactly what Frederic Bastiat suggested: “We must admit that our opponents in this argument have a marked advantage over us. They need only a few words to set forth a half-truth; whereas, in order to show that it is a half-truth, we have to resort to long and arid dissertations.” So, at the risk of trying to minimize the “long and arid” part of this process, below are the 10 things you need to know to be the judge – for yourself – if the conventional advice about cholesterol is correct. 1. The sine qua non of atherosclerosis is the presence of a sterol in an artery wall. How it gets there is the only thing we should be worrying about. Contrary to popular belief, atherosclerosis is not caused by many of things we think of, such as smoking, high blood pressure, diabetes, high LDL (the so-called “bad” cholesterol), or low HDL (the so-called “good” cholesterol). Some of these are certainly markers of risk – low HDL, for example – while others accelerate the process – smoking, for example – but none of these are the direct cause of atherosclerosis. The sine qua non of atherosclerosis is the presence of sterols (cholesterol or phytosterol) in arterial wall macrophages. Sterols are delivered to the arterial wall by the penetration of the endothelium by an apoB-containing lipoprotein, which transport the sterols. In other words, unless an apoB-containing lipoprotein particle violates the border created by an endothelium cell and the layer it protects, the media layer, there is no way atherogenesis occurs. If this is a bit confusing, don’t worry. It’s all made clear below. 2. Cholesterol is vital for life; no cholesterol = no life. Cholesterol is a 27-carbon molecule shown in the figure below. Each line in this figure represents a bond between two carbon atoms. That’s it. Mystery over. All this talk about “cholesterol” and most people don’t actually know what it is. So, there you have it. Cholesterol is “just” another organic molecule in our body. I need to make one distinction that will be very important later. Cholesterol, a steroid alcohol, can be “free” or “unesterified” (“UC” as we say, which stands for unesterified cholesterol) which is its active form, or it can exist in its “esterified” or storage form which we call … Continue reading The Straight Dope on Cholesterol: 10 Things You Need to Know – Part 1