Eating one tablespoon of olive oil a day could help you live longer, according to experts.
Olive oil, a key component of the health-giving Mediterranean diet, has long been said to be beneficial to health.
Now, medical consultant Dr Sarah Brewer and dietitian Juliette Kellow claim in their new book 'Eat Better Live Longer' that the oil could add years to your life.
They say the common cooking ingredient contains antioxidants which could help to prevent or slow down cancer growth and reduce the risk of heart attacks and strokes – some of the world's most common killers.
And it may reduce the damaging effects of cholesterol, blood pressure and age-related diseases, and improve cognitive function, the experts say.
Their claims add to years of scientific evidence suggesting the oil may help people avoid deadly diseases.
The oil is high in calories – 100 per tablespoon, according to Brewer and Kellow – so it should be consumed in moderation. They suggest one tablespoon a day.
But it is high in monounsaturated fats, which help to reduce cholesterol and cut the risk of heart attacks and stroke.
It also contains a lot of vitamin E which maintains healthy skin and eyes and strengthens the immune system.
Cancer and heart disease, which olive oil is thought to reduce the risk of, are two of the biggest killers of people worldwide.
One in three people in the UK will get cancer at some point in their life, and quarter of all deaths in the UK and US – hundreds of thousands of people a year – are due to heart disease.
'A review of studies found people with the highest intakes of olive oil compared with the lowest intakes were 34 per cent less likely to have any type of cancer,' Dr Brewer and Ms Kellow said. 'And particularly breast cancer.
Olive oil thought to have cancer-preventing antioxidants
'It’s not clear exactly how olive oil makes this happen, although lab-based studies show that polyphenols in olive oil may help to prevent the initiation and progression of cancer through their antioxidant action.'
The pair say extra virgin olive oil gives the most health benefits and is best enjoyed raw, the Daily Express reports.
On the other hand, virgin and pure oils are cheaper and better for cooking with.
Studies have in the past linked olive oil consumption to healthier blood vessels, a reduced stroke risk, a lower chance of depression, healthy cholesterol levels, reduced breast cancer risk, and lower incidences of Alzheimer's disease.
It may also help to prevent pancreatitis, liver damage, and inflammation in the intestines.
The oil 'mops up' damaging cells
Dr Brewer and Ms Kellow say: 'Extra virgin olive oil is also packed with polyphenols, many of which act as antioxidants and anti-inflammatories.
'This is a powerful combination – the antioxidants mop up cell-damaging free radicals, while anti-inflammatories combat unwanted inflammation in the body.'
They add: 'Many studies show a lower incidence of stroke in people who have good intakes of olive oil.'
Past research suggests oil ingredient makes cancer cells destroy themselves
Scientists got an insight into how olive oil could fight cancer during a study at Rutgers University in New Jersey in 2015.
Researchers found an ingredient in extra virgin olive oil, oleocanthal, kills human cancer cells without harming healthy ones, researchers found.
The oleocanthal works by rupturing a part of the cancer cell called the lysosome and releasing proteins which kill it.
When the scientists applied the oleocanthal to cancer cells in the lab they died very quickly – within 30 minutes to an hour.
‘The lysosome is the garbage dump, or the recycling centre, of the cell,’ said researcher Paul Breslin.
‘Once you open one of those things, all hell breaks loose.
‘The lysosome is isolated in the cell because it’s so toxic. If you rupture [it] the inside of it leaks out into the cell.
‘It’s full of aggressive enzymes that can tear apart anything that it comes into contact with.’
However, oleocanthal does not harm healthy cells – it just effectively puts them to sleep, and they return to normal the next day.