ZOE Science & Nutrition - Recap: Diet changes that could reduce bad cholesterol | Dr Sarah Berry

Episode Date: November 12, 2024

Today we’re discussing how the food we eat can lower cholesterol. It’s an important question, as high cholesterol can increase our chances of developing heart disease. Around half of adults have high cholesterol, and it gets more common as you age. So, how can we break this trend? Today’s guest, Professor Sarah Berry has led more than 30 human studies on cardio-metabolic health. It’s safe to say she knows a thing or two about heart health and cholesterol. 🥑 Make smarter food choices. Become a member a zoe.com - 10% off with code PODCAST 🌱 Try our new plant based wholefood supplement - Daily30+ *Naturally high in copper which contributes to normal energy yielding metabolism and the normal function of the immune system 📚 Books from our ZOE Scientists: The Food For Life Cookbook by Prof. Tim Spector Food For Life by Prof. Tim Spector Every Body Should Know This by Dr Federica Amati Free resources from ZOE: Live Healthier: Top 10 Tips From ZOE Science & Nutrition  Gut Guide - for a healthier microbiome in weeks Have feedback or a topic you'd like us to cover? Let us know here Listen to the full episode on Apple or Spotify

Hello and welcome to Zoey Recap, where each week we find the best bits from one of our podcast episodes to help you improve your health. Today we're discussing how the food we eat can lower cholesterol. It's an important question as high cholesterol can increase our chances of developing heart disease. Did you know that around half of adults have high cholesterol and it gets more common as you age? So how can we break this trend?

Today's guest, Professor Sarah Berry, has led more than 30 human studies on cardiometabolic health. It's safe to say she knows a thing or two about heart health and cholesterol. So the best way to illustrate just how effective food and our diet can be at lowering cholesterol comes from the portfolio studies. And these are key nutrition science experiments showing the power of food in relation to our health. And the concept of the portfolio diet isn't very straightforward. What you do is replace certain foods in your diet with other foods and ingredients that have been shown to lower cholesterol. And it's centered around four key elements.

It's centered around soy protein, plant sterols, tree nuts and soluble fiber. And did it work? Absolutely. So it was shown to reduce cholesterol by 30%. Now this is similar to the level of reduction that we see in cholesterol lowering from medication like statins. So 30%, that sounds pretty incredible. So does Zoe recommend this diet to people with high cholesterol? So it is an incredible dietary pattern to follow, but there's a catch with a portfolio

diet that it's really difficult to follow. So it's therefore more of a science experiment showing us what actually is the potential of food in terms of lowering cholesterol, rather than something that's really practical, I think, in the long term. Now, I think there's a more realistic dietary pattern that's also been shown to be effective in reducing cholesterol, and concept of the Mediterranean diet, which I think was invented by a bunch of nutritional scientists living a long way away from the Mediterranean because I've spoken to a lot of nutritional scientists now and every single one has a slightly different definition of what's in it, which is probably not surprising when you think that people living in Italy and Greece and Morocco and Israel all think they're eating a Mediterranean diet and if you go on holiday to these

places they're eating a very different diet. However I think everyone agrees Sarah that it's about eating plenty of fruit and vegetables, sort of whole grains, nuts and olive oils and then I think people start to argue a lot more about you know fish and lean meat and dairy products and the exact proportions. Yeah, that's right, Jonathan. And while it's not quite as drastic at the portfolio diet in reducing your cholesterol, it's a really sustainable diet that lets you enjoy food that would be cut out if you followed

a more restrictive diet like the portfolio. And so Sarah, to be clear for people who are listening to this, while eating foods like eggs that are high in cholesterol won't necessarily raise your cholesterol, there really are foods that can make your cholesterol go up or down? And if so, can you explain what those foods are? Yeah, so we know that actually dietary cholesterol, so cholesterol that's in the food that we consume actually has only a really small impact on our blood cholesterol levels. But what we do know is that saturated fat rich foods and particular types of saturated fat actually can have quite a potent effect on raising our blood

cholesterol. And these are the kind of fats that are found in red meats, for example, lots of ultra processed foods such as pastries, and also in some dairy such as butter. And what about carbohydrates? Because lots of people will be listening to this and saying, oh, well, so I've got high cholesterol, so I'm not going to eat any fat, and therefore my cholesterol is going to go down, which sounds really logical. Is it correct? No. So this is a big mistake, I think, that lots of people make. And

unfortunately, there's lots of really poor misinformation out there around people with high cholesterol being told to follow a low-fat diet. What we do know is that if you consume healthy fats and healthy oils, you can actually improve your circulating blood cholesterol levels. So rather than worrying about the amount of fat that you're consuming, you should be thinking about the types of fat. So the types of fat that we know increase cholesterol like I've just said are the saturated fats, but we know that the poly and monounsaturated fats that are found in many vegetable oils, nuts and seeds for example,

can actually reduce our blood cholesterol levels. Now the problem is if you take out the fat from foods so that you choose low fat versions of foods, it's got to be replaced with something because fat is actually the component in food that gives the lovely creamy mouthfeel, it carries much of the flavour. So if you strip out the fat, you've got to replace it with something that still confers that nice mouth feel and that great flavour to the food. Quite often, refined carbohydrates or sweeteners or other kinds of ingredients are added back into the food. And we know that these are really bad for us because we know that they impact your liver, which is involved in the production, like I said earlier, of cholesterol, but also they

increase another type of fat that circulates in your blood, which is called triglycerides. And we know that this is really unfavorable in terms of cardiovascular disease, if it's elevated as well. Amazing. Thank you, Sarah. So I think now that we understand a bit more that what we eat can cause high cholesterol and it could actually be a carbohydrate or a fat, can you be a bit more specific about what a listener should do to change their diet if right now maybe their doctor has told them that they have high cholesterol or they know that it's in their family and are there any sort of smart swaps that they could do without completely changing the way that they eat? Absolutely and I think it's making simple smart swaps as you call

them Jonathan that are personalized to your body but also your preferences that are ones that people will most likely stick to and therefore lead to sustained improvements in blood cholesterol. And actually your blood cholesterol can change really quickly from dietary changes. So we see changes in our studies, it's a little less 10 days to 14 days in blood cholesterol. So that should really motivate people that quick changes but sustainable changes will really have an impact. And the kind of things that you could do is to try and eat less red meat and less processed foods because these have the types of fat that we know increase your bad cholesterol.

You could introduce many fiber-rich foods such as beans and vegetables and also plant-based protein sources that we know will lower your cholesterol. And spreads are also a good substitute for butter since most spreads are made from vegetable oils so they contain these healthy unsaturated good fats that I've talked about the poly and monounsaturated fats. Although Jonathan this is quite a controversial area. And I remember from our previous episode that many of the foods that are high in cholesterol are also high in saturated fat and this may have led to some of the previous misinformation

suggesting that it's the cholesterol in some food, such as red meat that explains why red meat, for example, is bad for us. Yeah. And with regards to cholesterol, Jonathan, saturated fats are what's increasing the bad cholesterol in our blood, not that dietary cholesterol. Yes, and so there sort of could have been this confusion, right, when they looked at it because some of those foods happen to have high cholesterol as well. And so we now understand, I think this is right Sarah, like we understand better the mechanisms today. And therefore, the high cholesterol in the egg or the meat is no longer being blamed for it,

but actually the red meat still in the dock, still in trouble. We just understand that it's sort of different properties of the red meat that are causing us problems. Absolutely. So if we think of liver, for example, liver is high in cholesterol, but also high in saturated fat. If we eat lots of liver, we'll have an increase in bad cholesterol, but it's actually not the cholesterol in the liver that's going to cause this, it's the saturated fat. There's clear evidence to show that it's the type of fat that's important and not the amount of fat that's important to consider. So please don't follow a low-fat diet, but please change to really

healthy oils. And also be motivated in knowing that a dietary change can actually induce a change in your cholesterol in as little as two weeks. Thank you for listening to today's recap episode. I want to take 30 seconds to talk about something that's not talked about enough, menopause. Over half the people on the planet experience perimenopause. Menopause. Over half the people on the planet experience perimenopause and menopause.

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a particular menopause symptom by up to 37% for some women. We know how important it is for you to be able to take control of your own health journey. So we've created the Menoscale Calculator to help you score the frequency and impact of your menopause symptoms. Go to zoe.com slash menoscale to get your score. The calculator is free and only takes a couple of minutes. And by the way, we've spoken about perimenopause and menopause many times since starting the Zoey Science and Nutrition podcast. To find these episodes, simply search Zoey Menopause in your favorite podcast player.