Olive Oil Is Not Just for Salad
Shakespeare wrote many a wonderful play but he also wrote some heart-stopping poetry. ‘Shall I compare thee to a summer’s day?’ is a Shakespearean sonnet of some fame. Most of us will remember that opening line. I have often thought about it. The poet describes how his beautiful love is actually more wonderful than summer. Since I am English, as was Shakespeare, and our summers are often not the best I can appreciate the sentiment. Perhaps if Shakespeare had been born in a Mediterranean country with long, warm summers, clear blue skies and not much rain he might not have written this beautiful poem. There’s a thought. Well there are people who do indeed live where the sun shines all day long in the summer. They enjoy a different diet to the staple faire of England. This has serious implications for health; heart health, in fact.
The Mediterranean Diet
You have probably heard of the ‘Mediterranean Diet.’ ‘Eat and drink like someone from the Mediterranean and you will live longer’ seems to be the claim associated with the concept of this diet. Many people have suspected that even though French people, for example, smoke more than we do and eat just as much unhealthy fat, that perhaps there is something in their diet which accounts for their lower levels of coronary artery disease. Could that be olive oil? Olive oil, especially extra virgin (unrefined) olive oil, is rich in chemicals such as polyphenols, which are thought to have health benefits.
Glasgow Is Not in the Mediterranean
Dr William (Bill) Mullen sat across from me recently in a cafe in Glasgow in Scotland close to his lab in the University of Glasgow. Not too long ago, Glasgow was infamous as the ‘heart attack capital of the world’ but that has changed for the better in recent years. Bill is the Director of Biomarker Research and has had a long interest in how simple changes in diet could be beneficial to health and to detect biomarkers for disease at an early stage before there has been a significant negative impact. We spent about an hour there talking about olive oil and its health benefits and research Bill has led, studying, with mass spectrometry, biomarkers for coronary artery disease and other diseases and how they are affected by adding olive oil to your diet. We also discussed more broadly issues around biomarkers and their use.
Olive Oil and Coronary Artery Disease
The results, not to overstate it, are intriguing and even quite profound. Simply adding 20 millilitres of olive oil to your diet can have a big impact on your health, as measured by a biomarker panel for coronary artery disease (CAD), over a short period of time. A group of sixty-nine self-reported healthy volunteers were given either extra virgin olive oil (expensive, with high phenolics) or regular olive oil (less expensive, with lower phenolics) and asked to add 20ml a day of uncooked oil to their diet. They did this for 6 weeks with urine samples being taken at the start of the study and after 3 and 6 weeks for mass spec analysis using a proteomics approach. The biomarker panel, which monitors for pre-symptomatic coronary artery disease, consists of 238 peptides measured in urine samples. Interestingly both groups showed a marked improvement in their CAD score, indicating improved health, but not likely via the effect of phenolics. Something else in olive oil, common to both oils, is having an impact on CAD.
The British Broadcasting Corporation
Subsequent to the initial study, the BBC became interested in the olive oil story. A programme called ‘Trust me I’m a Doctor’ worked with Bill to further study the effect of olive oil versus other common oils on CAD. Two oils, rape seed oil and sunflower oil, were given to two groups of people as in the first study. Neither of these two oils resulted in a significant impact on CAD markers, unlike olive oil. So indeed there is something unique to olive oil that can be beneficial to heart health.
Back to the Cafe in Glasgow
The conversation continued and we talked more generally about biomarkers of disease. Bill made a comment about the general nature of many biomarkers used today. ‘At the moment, most of the biomarkers being used are signs of damage and not the initiators of the disease, they are late stage ones so by the time they show up it may be too late.’ I asked him about population screening and we discussed the problem of false positives when screening a whole population for disease. Bill concluded that it often made sense to use biomarkers to look at targeted groups. In the case of CAD people suffering from diabetes might benefit from screening of urine for CAD and for kidney disease, common outcomes of diabetes. By screening in this group, ‘We could maintain a constant vigil on how their cardiovascular and kidney profiles are progressing and try to intervene as needed.’ A second population identified as potential beneficiaries of a screening approach are those who live in rural and remote communities due to their distance from primary care. They could simply post urine samples to Glasgow and have their health monitored, visiting a hospital if indicated by the urinary biomarker tests, for kidney disease, two types of heart disease, prostate and bladder cancer and more.
Impact for Society
‘Food labelling is bleep’ said Bill. He didn’t actually say bleep. He said something different. Bill wants food companies to give clear, scientifically based messages. There is too much mixed messaging about food and health. Bill stated, ‘There was no real way of measuring if a food is actually good for you. This is the first time we’ve really been able to show this, in olive oil, a cohort effect. It is do-able by food companies to test the foods and show they have a health benefit. They can use these techniques to demonstrably show that new products have a health benefit. We need to get the European Foods Standard Agency to accept that our methodologies are useful.’ The reason this would be possible to undertake for health products is that the studies Bill and colleagues have undertaken need relatively few volunteers to participate to achieve results that can lead to clear advice, such as in the olive oil studies.
Bill continued, ‘Imagine if you went to your doctors’ and they gave you a health screen and imagine if they actually could say to you your cardiovascular marker is quite high, have you tried introducing olive oil into your diet and then a few weeks later you return and it’s come down, the patient would say I will carry on with that.’ After the BBC programme, Bill had lots of emails from the public asking for advice. Bill observed that it would be better for all of us if we could see that a simple change in diet really, really worked to improve our health rather than the use of mass medication, such as statins.
Like what you are learning?
Why do you go to work in the morning, Bill?
Yes, I did ask that question. Bill was emphatic. ‘I want to see something that has a benefit in society. If you can make folk healthier, that’s what I like. Food can have an impact. It can stop progression to bad health.’
This Doesn’t Taste Quite Like Olive Oil
Actually you cannot really differentiate extra virgin olive oil from adulterated oil just by taste or any other tests you might run at home, unless you have a well-equipped lab in the garage. Some olive oil does not have very much of the olive in it. Unscrupulous producers out there sometimes fake it. So if you take Bill’s advice and add olive oil to your diet for your health (although it also tastes good!) how will you know that it is the real deal since the oils it may be replaced with will not offer the same health benefit? Well, there are uses for mass spectrometry other than proteomics. Mass spectrometry is a powerful tool in detecting food fraud. I have written other articles about the power of mass spectrometry as an analytical tool in many areas if you would like to learn more (Amazing Orbitrap, Fourier Transforming the World). If you have a specific interest in the detection of food adulteration in general click here.
In addition, below you will see a simple infographic that describes what could be in your bottle of olive oil (some of it not so good), technologies used to analyse the safety and authenticity of your oil and other foods and beverages and some simple nutritional information. If you have a specific interest in edible oil testing (ThermoFisher.com/EdibleOilTesting) then we have a great deal of information to share with you.
How do you like your olive oil?
Here are some ideas. Well, you can pour it on your salad (obvious, I know), you can dip your bread in it (my favourite), you can knock it back like a shot of whiskey (not sure about that one), you could add it to some warm soup or to pasta after it has been served, you could eat olives, bruschetta with lots of oil, drizzle it on feta cheese. However you eat or drink your olive oil, it should replace some existing oil or fat in your diet as oil is very high in calories. Here is Bill’s favourite. He often has a sandwich for lunch and he soaks the bread in olive oil.
On that note, I hope you enjoyed reading this and I wish you good health. If you are going to knock back your olive oil like a shot of whiskey, good luck!
Silva S. et al., Am. J. Clin. Nutr. (2015) 101, 44-54