The food we eat can affect our body's ability to fight colon cancer cells.
The potential culprit: an excessive amount of certain omega-6 fatty acids - possibly from ultra-processed foods in the diet that can interfere with the anti-inflammatory and anti-tumor properties of another essential fatty acid, omega-3.
"There are mutations in the gastrointestinal tract every day, and these are usually quelled immediately by the immune system using omega-3 molecules or mediators," says Dr Timothy Yeatman, senior co-author of the study published in Gut, the journal of the British Society of Gastroenterology.
"But if your body has been subjected for years to a chronic inflammatory environment created by an imbalance of omega-6s, such as are typically found in ultra-processed and unhealthy foods, I think it's easier for the mutation to take hold and harder for the body to fight it off," explains Yeatman, a surgical oncologist and professor at the University of South Florida and the Cancer Institute at Tampa General Hospital.
Experts say diets in Western countries are often high in omega-6 fatty acids, due to widely available seed oils often used to fry fast food and produce ultra-processed foods, which now make up about 70% of the U.S. diet. The linoleic omega-6 fatty acid, which is found in corn, peanut, soybean, safflower and sunflower oils, is the most prevalent in American foods.
In many people's bodies, there is a significant imbalance between omega-6s and omega-3s - a November 2015 study found that linoleic acid levels have increased by 136% in the fat tissue of Americans over the past half century.
"Don't blame omega-6s, they're not to blame - the problem is a lack of omega-3 fatty acids," warns Harris, who is also president and founder of the nonprofit Fatty Acid Research Institute in Sioux Falls, South Dakota.
What are essential fatty acids?
Both omega-3 and omega-6 polyunsaturated fatty acids are essential for human health. However, our bodies cannot produce them on their own and must obtain them from the foods we eat.
Omega-3s - which are found in high amounts in oily fish like salmon, as well as flaxseeds and chia seeds, pecans, walnuts and pine nuts - support the body's cells, provide energy, support immune defenses and reduce inflammation when in optimal amounts (like most things, too much omega-3 can be harmful).
Omega-6s are also necessary for maintaining good health. These molecules stimulate hair and skin growth, regulate metabolism, strengthen bone health, and in some cases may even have anti-inflammatory effects.
However, omega-6s can also be converted into molecules like prostaglandins that signal the onset of inflammation - not bad when your body is trying to quickly fight off an invader or tumor, but devastating if left to fester for a long time. | BGNES
