A lot of times when I meet people and when I get to know somebody a little bit better and I get to meet them and talk to them in person, I start to find out that there's more common ground than there is opposing ground. But the internet seems to love taking a clip or a snippet of one thing and then having like this guy versus that guy kind of thing. Yeah, right. We end up getting put into little boxes, which I understand because of the nature of social media and 60, 90 second.
clips so you can lose a bit of context and nuance. But I listened to your episode with Stan and he's a super knowledgeable dude, firstly. And I was kind of nodding my head throughout that episode thinking, had we had a sort of quote unquote debate in person, it may not have been a productive, it would have been productive actually, that's a poor choice of words.
It might not have been the debate people had expected because we would have agreed on 90, 95% of things. It seems like a lot of times, especially when it comes to nutrition, that the answer seems to lie in the middle. You know, something like a keto diet comes along and okay, maybe the keto diet, maybe following this diet that is so high in fat isn't a good idea, but maybe for some people, maybe throwing away some carbohydrates wouldn't be a bad practice for them. When it comes to a plant-based diet, when it comes to a meat-based diet, maybe some of these ideas aren't necessarily bad per se. Maybe the...
the overall concept and idea of maybe people parting ways with the shitty diet that they might currently have, uh, would be the best thing for them. And when I hear some of your, uh, content, what I'm mainly hearing is like, I, you know, you know what, Mark, you, you probably should eat a little bit more plants. You probably should eat a little bit more vegetables. You probably should introduce some of these things that Simon's talking about.
And that's, that's what I tend to like to look at the most because I think people need help and they need options when it comes to nutrition. Yeah, I think, I mean, that's my philosophy, which may get lost online. But if someone's read my book, for example, they'll understand that I don't put forward one specific diet as the diet that's most optimal.
I speak about a theme, a sort of set of characteristics, and there are a number of ways that you can get there. And that could be low carb, it could be high carb, it could be a diet that's featuring animal products, or it could be diet without animal products. You can do an omnivorous diet very well. You can do a plant-based diet.
very well, you can do both of them poorly. And to your point at the start there, I think one of the reasons why it can become so confusing with lots of people kind of shouting about specific diets or one of the ways that I think people fall into that trap is overlooking context. So, so many of these studies, in order to properly interpret them and the overall body of literature and Stan spoke to some of these things, you have to understand the context. What is the the the dose that we're talking about when we're looking at a nutrient or a food, the sort of exposure of interest. If we're talking about saturated fats, what type of saturated fats?
It's an umbrella term. There are so many different types that have different effects on physiology. Yeah, there's something like stearic acid, which isn't shown to raise LDL cholesterol quite the same way as other fatty acids, right?
And people love to hear that because that's the predominant saturated fat in chocolate. So we can keep some chocolate in the diet. Okay, but...
What are we comparing to? So if we're eating less of something, the effect that that has on your physiology and then the health outcome, which is really what we care about most, will be dictated not only by what you're removing but what you're adding in. And then what's your genome like?
What's your genetic makeup like? And so a lot of that ties back to Stan's comments and he reiterated this a few times and it's something that I speak to is you have to measure. things at the beginning your your biomarkers to understand your biology and then when you go and and intervene whether it's for the purpose of disease risk reduction or it's the purpose of performance and and some sort of goal in the gym you have to measure first intervene and then come back and measure and that's really the only way to to act with intention i have a question you mentioned genetic testing so like you know we have Merrick Health that we work with and people get their blood work done, but when a lot of individuals getting their blood work done, right?
What are some things that you think they should be paying attention to to maybe make adjustments to their diet? I know we did talk a bit about ApoB But is there anything else that you think people should really be trying to pay attention to then they can start making changes to what? They're eating.
Yeah, there's a few I'm not I'm not a big one in terms of going out and testing just for hundreds of different genetic markers, I think it's circumstantial and you need to be specific to the results that you're seeing on paper. That can be very confusing, yeah. I think in your conversation...
I think 10 eggs came up. Yeah. So this is a great example, right? If someone has very high cholesterol levels and you wanted to decipher, are they overproducing cholesterol and just not being able to clear it back into the liver through the LDL receptors, or are they overabsorbing?
And the reason this is important is, and in your episode you spoke about dietary cholesterol. So for... For most people, dietary cholesterol affects their cholesterol to an extent, but nowhere near as much as saturated fat. It's not negligible, but if you're going to focus on something in your diet to reduce your serum LDL cholesterol or ApoB, it's going to be less saturated fat. That's the first place you would start.
But for a certain percentage of the population, they're considered hyperabsorbers. And maybe that's 10, 20% of people. So again, it's not a super small number of people. It could be one in five. How do you work out if that's you?
And what's happening there, firstly, is if you're a hyperabsorber, these people have genetic mutations where a receptor in their small intestine, the Neiman-Picc C1-like-1 receptor, complicated. Neiman-Picc C1-like-1. Complicated.
We were talking about that this morning before you got here. Very complicated name. I got a dollar for every time that came up. Right. Let's just simplify and say there's a receptor there that's like a door and that's going to dictate how much dietary cholesterol, the cholesterol that you eat is actually absorbed in through the small intestine into circulation.
Some people have a variation where that's upregulated. That receptor is also the same receptor where phytosterols, which are in plant foods, also come into circulation. And there's a test that...
you can do. So this is not specifically a genetic test, we're not testing that specific gene, we're looking at markers in the blood in this case, which would be representative of being a hyperabsorber and having a genetic variation that's causing increased absorption. You can actually measure these phytosterols in circulation.
The reason why that's important is when you measure just blood cholesterol, you have no idea of knowing was that... something that you absorbed in through the small intestine or was it something your liver produced? But if we're measuring phytosterols in the blood, we know that the only way that got in was through that gate.
So you can measure these as a company in PowerDX. I have no affiliation with them. Campesterol, cytosterol, and Dr. Thomas Dayspring talks about this a lot.
If you measure those and you get your results back and they're in that high or off the charts high level, then you know you're a hyperabsorber. And what that means is you now might be one of those people that wants to keep a closer eye on the consumption of eggs or shrimp, for example, that are very rich in dietary cholesterol. So that's a very quick and easy way for someone to rule out do they have a genetic variation that's causing them to increase the absorption of dietary cholesterol. Gotcha. Why the importance on saturated fat?
What do you think is going on there? And in connection to saturated fat and potentially heart disease, I would imagine that it matters if you're overeating, like in general. So if you overconsume calories, has that been, has there been any studies done with saturated fat?
Somebody consuming what someone would consider to be a lot of saturated fat, but still controlling their calories to be, I guess, at like maintenance levels. Is there any evidence that shows that that could potentially cause damage to the heart? Yeah, things are...
Usually much worse when you have energy toxicity, whether we're talking about lipids or we're talking about accumulation of fat in the liver and insulin resistance. But certainly if you dial up saturated fats and lower polyunsaturated fats in a eucaloric sort of weight maintenance context, you will still see increase in APOB, significant increase. And what happens is the mechanism there is relatively simple.
Certain saturated fats, particularly the ones that are found in cuts of red meat and butter, they down-regulate the LDL receptor at the liver, which means you have less of these sort of gateways for ApoB-containing lipoproteins in the blood to come back in the liver. As a result, they start to build up in the blood. I often use an analogy of shipping cargo ships.
So cargo ships are out in the ocean and they're carrying these containers on the top. And we can kind of think of that cargo ship as the ApoB. That is the protein.
And on top of that ship is triglycerides and cholesterol. It's the protein that we need to carry those things because they're not fat soluble. So that allows us to transport, particularly transport triglycerides throughout the blood and get them to tissues where they'll oxidize and use them to produce energy ATP. When you have large amounts of saturated fat in the diet and the LDL receptor gets downregulated in the liver, you have more and more of these cargo ships in circulation.
So let's imagine we're at a port. We're looking at cranes that are clearing the containers off of these cargo ships. Ordinarily, that cargo ship will come in.
Hopefully, there's not much of a delay. The crane drivers are quite quickly clearing the containers off. And that cargo ship.
leaves. As you have elevated levels of ApoB containing lipoproteins, you're getting a backlog of these cargo ships in the port. And we can imagine here that the crane drivers are like the LDL receptor. So let's say we eat more saturated fats.
Some of these crane drivers are going on strike or they're taking a break. So we're getting less clearance. We now have more of these cargo ships building up in circulation and they're just waiting.
They're dropping their anchor. and we're increasing the likelihood that they're going to enter the artery wall. And they have been found to be the causal component of atherosclerosis. So APOB is our best marker of our risk of atherosclerosis.
It's those lipoproteins that are dropping anchor in the artery wall and then kick-starting that inflammatory cascade, which ultimately leads to the development of... fatty plaque and cholesterol being sort of deposited into the artery wall which many decades down the track can result in cardiovascular events. What's a general recommendation that you would have for somebody you know you say maybe you know watch your saturated fat and then how do you think someone has a way to like go home and actually utilize that in their day-to-day? So generally I guess let's start with a high level food perspective what are we talking about here in terms of swaps? It looks like shifting from diets that are rich in fatty cuts of red meat and butter to diets that are more emphasizing fatty fish, nuts and seeds, tofu, those sorts of foods.
You can think about a Mediterranean style dietary pattern. Now, not everyone's going to get the exact same result because the genes will play a role in those LDL receptors and how they're expressed. So you have to come back to blood work.
So you make shifts to your diet. Maybe you're downshifting on some of the fatty cuts of red meat. And you might be swapping some of those with leaner cuts of red meat, but you might be swapping some of those serves with fatty fish, some of those serves with lentils, tempeh, tofu, and then you're retesting.
And so I usually recommend people approach it like that and then titrate accordingly based on how your body's responding to that. Knowing that you want to achieve an APOB level that we know is associated with low risk of atherosclerosis depending on your overall risk profile. Stan spoke to this.
I'll reiterate it. If you are healthy, low risk of cardiovascular disease, so you're not someone with type 2 diabetes, you haven't had a cardiovascular event, you don't smoke, you're healthy body weight, then you want to be south of. 80 milligrams per deciliter for your ApoB. And if you're someone that's higher risk, let's say you've already had a cardiovascular event, you have type 2 diabetes, you have high blood pressure, which is a big risk factor for cardiovascular disease, maybe you have a history of smoking, all of these things that can damage the endothelium, then you want to be 50 milligrams per deciliter or south of that.
So it's really about understanding. high level, what kind of swaps are available to you. Make those in a way that you're able to still enjoy your diet and sustain it and then retest. And from there, you can either stick with that if your results are good and you're happy with it, or you can make further changes.
Then there's some discrepancy between the saturated fat that you might find in steak versus saturated fat that you may find in dairy. Yes, and even within dairy, it varies depending on the type of dairy. So dairy foods contain a milk fat globule which affects the way that that saturated fat is absorbed and then the subsequent effect that it has on cholesterol.
And when I say cholesterol, I'm more specifically talking about ApoB here. The more refined that butter is, the more you break down that fat globule. And so butter is refined relative to the other forms of dairy and it has a much more marked... market effect on your ApoB.
Milk sort of sits in the middle and then the fermented. dairy foods seem to be quite neutral. They're certainly superior when you look at studies comparing red meat to forms of yogurt or milk. You'll see that the dairy foods are beneficial. They'll actually lower ApoB relative to red meat.
But this brings us back to this important concept of compared to what. There's a meta-analysis by Chen et al. that's looked at. specifically at dairy fats and their effect on cholesterol relative to other foods. And you see exactly that. Relative to fats in red meat or butter, other forms of dairy will lead to a reduction in cholesterol.
But relative to plant sources of fats, polyunsaturated fats from plants, if you were to swap those dairy fats for polyunsaturated fats from plants, you'd see a further reduction. So it all comes back to what are we comparing to? Then we have to zoom back out and think about someone's overall dietary pattern and look at their blood work. They can make changes based on what those results are.