Nutritionist Confirms Long-held Belief About Olive Oil and Health
It’s usual advice for people watching their waistlines or looking to eat healthier to be wary of how much oil they use in cooking. But that doesn’t mean we should completely cut out oil from our diets. Indeed, extra virgin olive oil in particular can have many benefits for our health.
Numerous studies have shown that consuming olive oil – especially extra virgin olive oil (EVOO) – can have many benefits for our health. For example, the Spanish Predimed study (the largest randomized controlled trial ever conducted on the Mediterranean diet) showed that women who followed a Mediterranean diet supplemented with extra virgin olive oil had a risk of breast cancer. 62% lower than women who were advised to follow a low-fat diet.
Experts who have since reviewed several scientific studies looking at the Mediterranean diet and its effects on chronic disease conclude that EVOO is one of the main reasons the diet protects against breast cancer. There is also evidence that EVOO may protect against type 2 diabetes and possibly even Alzheimer’s disease.
So what makes extra virgin olive oil better for us than other types of cooking oil? The answer lies in its composition.
Besides its fat, EVOO also contains many natural substances, such as polyphenols. Polyphenols occur naturally in plants and have been linked to many health benefits, such as reducing the risk of cardiovascular disease and cognitive impairment. Studies also seem to show that one of the main reasons why EVOO is beneficial to our health is due to the polyphenols it contains. Polyphenols are believed to have many benefits in the body, such as improving the gut microbiome.
Research shows that polyphenols in extra virgin olive oil are linked to a lower risk of cardiovascular disease. In fact, when researchers stripped EVOO of its polyphenols, they found that it didn’t protect the heart from disease either. One of the heart health benefits of EVOO is believed to be that its polyphenols prevent cholesterol from oxidizing. It is when cholesterol reacts with oxygen and oxidizes that it damages blood vessels.
The reason EVOO contains such high levels of polyphenols is that it is produced by simply crushing olives. More processed versions of olive oil — such as light olive oil or spreads — don’t contain as many of these polyphenols. This is because creating them requires more processing, which results in the loss of most polyphenols.
How Other Oils Compare to Olive Oil
Most other cooking oils, such as sunflower oil or canola oil, are made from seeds. The seeds are very difficult to extract from the oil, so they must be heated and the oil extracted with solvents. This means that most of the polyphenols in the seeds are lost during production.
Rapeseed oil (also known as canola oil or vegetable oil) is sometimes claimed to be a healthy alternative to EVOO. Although there is some evidence that raw (i.e., it has not been heated during cooking) canola oil can temporarily lower cholesterol levels, there is currently no evidence. that it may reduce the risk of developing diseases associated with high cholesterol, such as heart disease.
Of course, most of us use oils for cooking. But when an oil is heated to too high a temperature, it reacts with the oxygen in the air, causing the fat in the oil to break down. This can lead to the formation of harmful substances that irritate the eyes and even carcinogens. Rapeseed oil is particularly prone to this process – called oxidation – especially when used repeatedly for frying.
The polyphenols help prevent fats from oxidizing and so EVOO remains stable even when used at the temperatures required for shallow frying foods. Since rapeseed oil and other oils such as sunflower oil contain lower levels of polyphenols, the fats are not as well protected from breaking down during cooking.
Another important reason for EVOO’s stability is that its main type of fat is monounsaturated fat. It is both a healthy fat and quite resistant to oxidation. Monounsaturated fats are also the main type of fat in rapeseed oil. But unlike EVOO, canola oil also contains fairly high levels of polyunsaturated fats called alpha-linolenic acid. It’s not very stable, and that’s another reason why overheating canola oil isn’t a good idea.
Coconut oil is often advocated as a healthy oil to use. But coconut oil contains high levels of saturated fat, which can significantly raise low-density lipoprotein (or LDL) cholesterol levels (sometimes called “bad” cholesterol). High LDL cholesterol is linked to cardiovascular disease, and the saturated fats in coconut oil have been shown to increase the risk of heart disease.
One of the important messages about EVOO is that it appears to be much more effective when consumed as part of a Mediterranean diet – which is generally high in vegetables, fruits, legumes, grains, fish and olive oil. ‘olive. This is likely because extra virgin olive oil and its beneficial polyphenols interact with other foods, including vegetables consumed on this diet. The Mediterranean diet is linked to a lower risk of many chronic diseases, including cancer, cardiovascular disease and Alzheimer’s disease. It might just make the extra price of EVOO worth paying.
This article was originally published on The conversation by Richard Hoffman at University of Hertfordshire. Read it original article here.