Michael Mosley “Welcome to Glasgow, a vibrant, exciting city, but also one where more people die of heart disease than anywhere else in the UK. We’ve come here to do a big experiment, to see if changing just one thing about your diet can give you the benefits of a Mediterranean lifestyle, without you having to move to the Med. A Mediterranean diet; fish, olive oil and lots of fresh fruit and vegetable.
How Olive oil can improve your Heart Health
In countries like France and Spain, they live longer, and have lower levels of heart disease, and many put it down to their Mediterranean diet. It’s full of vegetables, fish and less meat than we’re used to.
But could it be that the key is actually simpler – just one magic ingredient? Olive Oil.
Now, we consume a lot more than we used to, but the amount we knock back is nothing compared to our Mediterranean cousins. The French consume about twice as much as us, the Spanish 14 times as much, and the Greeks a whopping 20 times as much.
The trouble is heart disease takes years to manifest, and there’s never been a way to test whether one particular food can really make a difference. Until now.
The Wonders of a Mediterranean Diet
Because, here in Glasgow, they’ve developed a brand-new scientific technique that can do this for the first time. And it centres on another golden liquid.
This is a flask of human urine – my urine, to be precise. It contains waste products from my body bit it’s also, in its own way, medical gold, as it contains information about processes that are happening deep inside my body. That information comes in the form of particular chemicals in the urine – proteins – which the team can detect in the lab. And what’s really exciting is that they can work out a protein fingerprint for different diseases.
Proteomics – Dr Bill Mullen
The technique is called proteomics and it’s being pioneered by Dr Bill Mullen”
Dr Bill Mullen “If we monitor the proteins in the urine,we can monitor what’s happening in the cells in the body.”
Michael Mosley “So somebody who, for example, has got heart disease will start to produce different proteins in their urine to someone who has a healthy heart.”
Dr Bill Mullen “There will be a different fingerprint of these proteins in their urine and we can detect that before the person actually has any symptoms of the disease.”
Michael Mosley “I guess it’s very different from measuring things like cholesterol in the blood because cholesterol in the blood is basically a risk factor. It doesn’t tell you whether you have heart disease, it just tells you you’re at greater risk.”
Dr Bill Mullen “That’s correct, yes, but when our proteomics fingerprint shows that you have heart disease, we’re measuring the disease itself, not the risk of developing the disease.”
Michael Mosley “This new technique can detect disease before you have any symptoms at all. It’s so precise that over just a few weeks, Bill thinks we can use it to measure whether consuming olive oil, as the marketing suggests, can improve heart health. So his team in Glasgow are running a trial of 70 people and I’m one of them. I start by swapping my flask of urine for a bottle of olive oil. Bill’s team will test my urine along with the other volunteers’ to determine the health of our hearts. And we’ll have to take 20ml of the oil every day for six weeks. Any special tips?”
Dr Bill Mullen “Well, it has to be consumed raw. Cooking with it tends to degrade the compounds that are meant to be good for you in it. So the health message is that it’s raw.”
Heart Health Benefits of Olive Oil
Michael Mosley “But there’s a twist. Half the people in the study are given regular olive oil – the other half, extra virgin. I won’t be told which I’ve got. The more expensive extra virgin olive oil has been claimed to be better for your heart than regular olive oil because it doesn’t go through any processing, so it contains a lot more natural chemicals from the olive plant. This study will be the first real test.
Now, I’m really looking forward to this, but I’m also a little bit sceptical, because I think the benefits of the Mediterranean diet come from the whole thing, not just from the olive oil.
Nonetheless, however, I’m going to add a couple of dessertspoons to my daily diet and see what happens. Compared to some of the things I’ve done in the name of science, consuming olive oil is a pleasure! On salad. On bread.Or even just as it comes.
And after six weeks, the scientists analyse everyone’s urine again.to see if taking the oil has made any difference. So – time for the results.”
Dr Bill Mullen “Well, the good news is that the results show there was a positive effect.”
Michael Mosley “First the results from those taking the extra virgin olive oil. On average, the levels of particular proteins that signal heart disease fell significantly over the six weeks. That’s a fantastic result in such a short period of time.”
Dr Bill Mullen “This is one of the beauties of this test, that I think is really good for measuring the effectiveness of food in changing your health.”
Michael Mosley “And what about the normal olive oil? Well, the results show it has exactly the same effect. It seems that any olive oil is good for you. I wondered if I was going to put on a bit of weight knocking back all that oil, but actually, it made no difference.”
Dr Bill Mullen “Well, the 20ml of olive oil which is sort of the recommended amount that’s fine. I would recommend no more than 20ml of olive oil a day, and the best thing to do is replace fat in your diet with olive oil.”
Michael Mosley “So we might finally have identified at least one element of that famously healthy Mediterranean diet. A little bit of olive oil a day can improve your heart health in just a few weeks. And it doesn’t seem to matter which kind, so you can save some money by choosing the regular sort rather than that fancy bottle of extra virgin.
But olive oil isn’t the only oil that’s marketed as being good for our hearts.”
Gabriel Weston “We know now that adding just 20ml of raw olive oil to our diet every day can be really good for our heart. But we want to go a step further to discover if other oils can be beneficial, too. The kinds of fats and oils we eat have long been a hot topic. For decades, saturated fats, like butter and lard, have been seen as the devil’s work, linked to high cholesterol and heart disease. So we began to replace them with vegetable oils, which contain healthier, unsaturated fats. In fact, no matter which oil you choose, it will be made up of three types of fat.
All vegetable oils contain a combination of polyunsaturated, monounsaturated and saturated fats. And for years now, the health benefits of each of these have been the cause of much debate.
Alternative Vegetable Oils for a Mediterranean Diet
In the 1980s, we were bombarded with marketing for polyunsaturated fats, like those in sunflower oil. These were thought to lower our cholesterol and be good for our hearts.
Then, in the 1990s, the marketers began to sell us the Mediterranean diet dream, with olive oil. This oil is rich in monounsaturates, also thought to reduce cholesterol.
Today, another oil is getting a lot of hype – rapeseed. Like olive oil, it’s high in monounsaturates. But which of these is really best for us?
To find out, we’re going into oil in a big way. So we’ve recruited 75 volunteers. All of these volunteers will undergo the same tests as were earlier undertaken by the olive oil group.
One group of volunteers took 20ml a day of sunflower oil, high in polyunsaturated fats.Another group took rapeseed oil, high in monounsaturates. We wanted to find out whether either of these could match the heart benefits of olive oil.
Dr Bill Mullen “The sunflower oil, which is the one that’s rich in polyunsaturates which allegedly have a protective effect against cholesterol, showed no change in our biomarker for heart disease.”
Gabriel Weston “So, after all the marketing for polyunsaturates and sunflower goodness, there’s no evidence in this experiment that it’s good for our hearts. But what about rapeseed oil, high in monounsaturates, instead?”
Dr Bill Mullen “When we looked at the one that was high in monounsaturates, which was closer to what we believe olive oil is, again there was no change in that on our biomarkers for heart disease.”
Gabriel Weston “A real surprise then. Rapeseed oil, which has fewer saturated fats and almost as many monounsaturated fats as olive oil, should, according to the latest theories, have been at least as good for us as olive oil. But according to this test, it’s not. So to find the secret of olive oil, it’s back to the drawing board.”
Dr Bill Mullen “We’ve shown that polyunsaturates and the monounsaturates that are in rapeseed oil and in sunflower oil seem to have no effect on our cardiovascular disease biomarker. So really it must be more complex than just simply the amount of monounsaturates in an oil, or the amount of polyunsaturates in an oil.”
Gabriel Weston “So we should be sceptical of the marketing messages about oil. As ever, it’s not as simple as they suggest. But the good news is that we have shown that olive oil in your Mediterranean diet really is good for us.
It turns out that this ancient golden liquid really does hold the key to a healthier heart – and we’ve found nothing to match it. Now, the key to exactly why it does that is still a mystery. But the take-home message is, take a couple of spoonfuls of this every day, doesn’t matter if it’s the expensive extra virgin option or the cheaper stuff, as long as it’s raw, and not cooked. The Mediterranean diet could be your Mediterranean dream.”
All of the above information came from the BBC series Trust Me, I’m a Doctor
Mediterranean Diet for Heart Health – Mayo Clinic