For years, olive oil has been hailed by doctors for protecting our hearts and keeping us sharp in old age.
But scientists now believe oleic acid, a common fat contained in olive oil, helps fat cells grow and multiply, potentially driving weight gain quicker than other oils.
Home cooks should therefore ‘moderate’ their olive oil consumption, ‘especially high-risk individuals,’ advised US researchers, who carried out the study.
‘If someone is at risk for heart disease, high levels of oleic acid may not be a good idea,’ they added.
It comes as a growing number of experts have urged caution over consuming olive oil in excess over fears it makes consumers more prone to high cholesterol and heart disease.
In the fresh study, scientists fed mice a variety of specialised diets enriched in specific individual fatty acids, including those found in olive oil, coconut oil, peanut oil, milk, lard and soybean oil.
They found oleic acid specifically, boosted a protein called AKT2 and reduced the activity of another protein called LXR.
This led to an uptick in cells that grow and form new fat cells.
Scientists now believe oleic acid, a common fat contained in olive oil, helps fat cells grow and multiply, driving weight gain quicker than other oils
For years experts have advised that cooking with a splash of olive oil is safe. It is in fact the preferred cooking oil of many professional chefs and dietitians alike. Dua Lipa (pictured) and her fans drizzle it on ice cream
Writing in the journal Cell Reports, the scientists said: ‘Relatively low levels of dietary oleic acid show beneficial effects.
‘But higher levels of oleic acid consumption have detrimental effects on cardiovascular health and mortality.’
Dr Michael Rudolph, an assistant professor of biochemistry and physiology at the University of Oklahoma and study co-author, also said: ‘We wanted to know whether simply overeating a diet rich in fat causes obesity, or whether the composition of these fatty acids that make up the oils in the diet is important.
‘You can think of the fat cells as an army.
‘When you give oleic acid, it initially increases the number of “fat cell soldiers” in the army, which creates a larger capacity to store excess nutrients.
‘This means that over time, obesity can occur, which can then lead to cardiovascular disease or diabetes if not controlled.’
He added: ‘I think the take-home message is moderation and to consume fats from a variety of different sources.
Millionaire biohacker Bryan Johnson claimed he drinks a few tablespoons of olive oil each morning, part of his expensive and unproven diet aimed at turning back the clock
‘Relatively balanced levels of oleic acid seem to be beneficial, but higher and prolonged levels may be detrimental.’
For years experts have advised that cooking with a splash of olive oil is safe. It is in fact the preferred cooking oil of many professional chefs and dietitians alike.
It is a crucial component of the Mediterranean diet, which has become extremely popular in recent years with a wealth of studies touting its benefits for longevity, reducing frailty and warding off cancer.
The diet involves largely shunning dairy, red meat and alcohol, while tucking into fruit, vegetables, wholegrains, olive oil, oily fish, nuts, seeds and pulses.
Dua Lipa and her fans drizzle it on ice cream. Bodybuilders on Reddit claim to guzzle it to bulk up. Jennifer Lopez credits it for her radiant skin.
And Silicon Valley biohacker freak Bryan Johnson, who drinks several tablespoons with breakfast, sells his own brand of olive oil as part of an unproven longevity diet.
Influencers also claim the golden liquid has all sorts of benefits like alleviating bloating and constipation, helping your body absorb nutrients better, supporting your hair and skin health, and even treating hangovers.
But other experts have previously suggested there may be a link between olive oil and weight gain, as well as an increased risk of heart disease.
New York dietitian Michelle Routhenstein had a client who would consume a whole cup of the stuff each day, ‘believing it to be exceptionally healthy,’ she told MailOnline.
‘However, this extreme behavior not only hindered his weight loss efforts but also adversely affected his cholesterol levels, as such high volumes of olive oil can be high in saturated fat, counteracting its purported benefits,’ she said.
‘Excessive consumption of olive oil without portion control can lead to an imbalance in energy intake, potentially contributing to positive energy balance and subsequent weight gain or difficulty in achieving weight loss goals.’
Dietitian Veronica Rouse added: ‘It’s important to be careful when listening to influencers who may sometimes unintentionally contribute to this overemphasis due to their personal experiences or endorsements, not always backed by an understanding of nutrition science.
‘It’s crucial to discuss any change in your nutrition plan with your health care team or registered dietitian.’
