**Podcast Episode: EP417: Cholesterol—Separating Fats from Fiction**
**Dr Warrick Bishop:** Welcome, my name's Dr Warrick Bishop. I'm a cardiologist, an author, and a keynote speaker. I'm the CEO of the Healthy Heart Network. I'm all about trying to help people live as well as possible for as long as possible. Heart disease is huge in Australia. Every 20 minutes, someone suffers a heart attack. Most of these could probably have been avoided if only we knew what to do. This podcast is all about helping you understand blood pressure, weight, and cholesterol for better health. If you enjoy this podcast, I would be honoured for a five-star review. You can share it with your family and friends. It may well save someone you love.
**Warwick:** G'day, it's Warwick here, and thank you for joining me. If you don't like the intro, and you think it goes a bit long, and you don't like the voice of that woman, or you don't like the extra, can you please drop us a note at info@drwarwickbishop.online? I'd really appreciate the feedback because I keep talking to John and saying I'm not 100% sure I like this lady, and I think it should be a bit shorter. So if you agree with me, please let me know.
Today, I want to talk about cholesterol. Why is that? Well, it's probably what I've been doing for the last 15 odd years, so I should at least be a little bit passionate about it. By the time you listen to this, there's an extremely good chance that the book that I've co-authored with Karam Kostner, my good friend, and had Penny Edmond as our co-writer help produce, called *Cholesterol Explained*, will have been released. So, I'd love to tell you a little bit about it, give you a teaser if you like, so that you might be interested in going and perhaps purchasing a book for yourself or for someone you love.
So, let's jump into it. A few basics to start with. It's really important to understand that cholesterol isn't inherently bad. In fact, it's essential. The body uses it to build cell membranes. It's important for the sex hormones, it is part of vitamin D synthesis, and it's used in bile acid production. So, you sort of need it. It gets moved around the body in lipoproteins. When I say lipoproteins, I want you to think of little particles, little balls made of protein that carry cholesterol around.
So, these little balls, these lipoproteins, are actually what we measure in the bloodstream. We don't actually measure cholesterol because cholesterol is a fat. If you just had fat floating around in serum, in our plasma, in our blood, well, that fat, just like cream in milk, would float to the top eventually. So, cholesterol, the molecule, which I just told you we use for cell membranes, sex hormones, vitamin D, and bile acid production, is not the same as what we measure in blood tests. What we measure in blood tests is the cholesterol in the lipoprotein particles.
And we've got different particles: low-density lipoprotein, that's the so-called bad one you may have heard of, and high-density lipoprotein, HDL, the so-called good one. So, it's important you get that fundamental distinction: cholesterol the molecule versus cholesterol in the particle. I don't want to be a spoiler, but we do touch on that in the book from the get-go.
Well, it's really important to understand that the cholesterol itself can end up in arteries, and when we look at cholesterol ending up in arteries, it's closely linked to the LDL particle. When we think about cholesterol building up in arteries, we've got a very strong correlation between that progressing and increased LDL levels, LDL particle levels within the bloodstream. But it's not always the case. It is more complicated than that.
What we can see is people with high LDL particles and not much plaque. Interestingly, we also find people with good levels of HDL cholesterol, the so-called good one, where it's not protective. We've started to understand that HDL, so-called good cholesterol, is not always good. We've also started to learn that LDL, bad cholesterol, is not always bad. Additionally, we've started to understand that triglycerides probably matter more than what we used to believe.
Maybe not necessarily triglycerides being direct problems, but being the association to changes in metabolic pathways that is the problem. Raised triglycerides are often associated with insulin resistance, poor metabolic health, and higher risk. They may be related to different particle sizes. The LDL cholesterol particle is different in an environment where triglycerides are higher. So, it's really quite complicated to predict risk super accurately.
We talk about this in the book because the particle and particle numbers are really important to take into account. By looking at particle numbers, you can start to discern large and small particles separate from the amount of cholesterol. Still important. The triglyceride to HDL ratio is a really powerful metabolic marker, so we can look at things like that.
Lipoprotein little a is a genetic lipoprotein particle that has a very high affinity for ending up in coronary arteries. It's really bad cholesterol, LDL cholesterol, or LDL-C. But it's worse; it's very bad LDL cholesterol. It's a very closely related particle, but it's so closely linked to genetic causes of premature heart disease. It's really important to be aware of this. High levels of this can certainly be associated not only with premature coronary disease but even atherosclerosis.
Importantly, in the book, when it comes to predicting risk, we talk about imaging the arteries and trying to understand for the individual we're looking at, do we see plaque building up or not? Irrespective of their blood tests, irrespective of how these people look on the outside, what's actually happening in the arteries? This is really, really important because you can have what look to be, for all the world, perfect cholesterol numbers, but still have really significant build-up, if you like, calcification within your arteries. And you don't know unless you look.
One of the things we really wanted to get across in the book is there seems to be, if you like, a conundrum around statins, uncertainty about statins, and personalized risk. So, we wanted to talk about the controversy. We wanted to talk about some of the barriers and really want to articulate, you know, are statins useful? Yes or no? Well, they are. But it's really important that you find the right person for them to be useful for.
Of course, when you stop and think about it, that doesn't mean statins are good or bad. It just means you have to find the right person. Take Panadol. Is Panadol good or bad? Well, it's neither. But if you've got a headache, it's really good for you. If you don't have a headache, why would you take it? We talk about this actually quite a fair bit of detail in the book because it's so important, in my opinion, to be as precise as possible for the individual so that we've got the most information available to make the best decisions.
Are statins good or bad? Neither. They're appropriate in the right circumstance. Are there side effects from statins? Well, show me a medication that doesn't have side effects. Not possible. The issue is understanding what's going on in the person's arteries and matching that situation with the best decisions for that individual going forward.
So, we've talked about the basics of cholesterol. We do need it. What we sort of measure, particle versus molecule. How do we predict risk? And we've touched on some of the uncertainty around statins and confusion. But we cover this in a lot of detail in the book. So, if it really is a topic that you're interested in, I'd love to invite you to go and check the book out.
If you don't want to buy it, but you do want to read it, please go to your local library and just ask them to get hold of it for you. It's going to be called *Cholesterol Explained*, and it's going to be written by Dr. Warwick Bishop and Karam Koster, co-authored by Penny Edmond. But if you ask your library to access it or purchase it for you, then at least I know the book will be getting out there and into the hands of people who might find it beneficial.
As we wrap this one up, cholesterol matters, but it's more complicated than good or bad. It's more complicated than blood tests. We want to really start to understand that cholesterol is all about inflammation, insulin resistance, factors within the artery, blood pressure, lifestyle choices, the whole lot, including family history.
Next time, I'm going to be talking, well, in my next couple of podcasts, I'm going to be touching on things like saunas and what their benefits are. I'm also going to be talking about keeping stronger as you age. Could that help your brain and your bones? Probably could. Stay tuned.
I hope you've enjoyed today's podcast. Please give us some feedback if you're inclined. Otherwise, I'd love you to share, subscribe, and tune in next time. Until next time, though, I hope you are well. I genuinely wish you live as well as possible for as long as possible. Take care, and bye for now.
**Warwick:** Hi. Ever wondered what your risk of heart attack is? You should. It's the single biggest killer in the Western world. We're talking one death less than every 30 minutes in Australia, one death less than every 60 seconds in the United States, and nine million deaths globally per annum.
Well, how do you check your risk? You can go to www.virtualheartcheck.com.au. You'll find out about your risk and what can be done beyond that to be even more precise.
