Doctors are warning that using too much could trigger tumour growth.
A new study has revealed that popular cooking oils used in ultra-processed Western diets could be causing a surge in colon cancer cases in young people.
The research, which was conducted by a US government-led group, found that unhealthy seed oils like sunflower, rapeseed, canola, and corn may trigger chronic inflammation in the body.
Until now, evidence linking cooking oil to colon cancer has been inconclusive, but the recent American study identified seed oils as a possible contributing factor.
The group of researchers examined tumours from more than 80 people with colon cancer, aged between 30 and 85. The results showed an increase in levels of bioactive lipids – small oily molecules produced when the body metabolises seed oils – compared to healthier fats.
As well as increasing inflammation, bioactive lipids hinder the body’s natural healing process and foster tumour growth.
The researchers recommended oils rich in omega-3 fatty acids, found in avocados and olives, as a healthier alternative.
Timothy Yeatman, a co-author of the study and a professor of surgery at the University of South Florida, said: “It is well known that patients with unhealthy diets have increased inflammation in their bodies.
“We now see this inflammation in the colon tumours themselves, and cancer is like a chronic wound that won’t heal – if your body is living off of daily ultra-processed foods, its ability to heal that wound decreases due to the inflammation and suppression of the immune system that ultimately allows the cancer to grow.”
“We don’t know the full effects of these ultraprocessed foods on our body, but we do know that that’s a major thing that’s changed from 1950 onward,” Yeatman added. “Young people today, particularly rural and impoverished people, are being exposed to more of these processed foods than anybody else because they’re cheap and they’re in all the fast-food restaurants.”
Related links:
He continued: “Omega-6 is an essential fatty acid. You’ve got to have it—but you don’t need it at [a ratio of] 30 times to 1. So it’s like everything else. It should be in moderation. But the problem is we’ve massively overdone the amount of seed oil in foods. And I don’t think seed oils are necessarily good for you because we get omega-6s from all sorts of other sources.
“Not everybody with seed oil exposure will probably suffer a problem from it. But I think there’s some link there.
“These links are hard to prove because we’d have to have a dietary history on people for years. More investigations are needed, and someone needs to prove that seed oils, taken in the excess amounts they’re given to us, are truly safe. And that hasn’t been proven yet to me, so I think the default should be reduce them until you know.”
