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The food you eat may affect your body’s ability to fight cancer cells in the colon, according to a new study.

The potential culprit: an excess of certain omega-6 fatty acids — perhaps from highly processed foods in your diet — which can interfere with the anti-inflammatory and tumor-fighting properties of another essential fatty acid, omega-3.

“There are mutations in the gastrointestinal tract every day, and usually they are immediately suppressed by the immune system with the help of molecules or mediators of omega-3 fatty acids,” said Dr. Timothy Yeatman, senior co-author of the study published Tuesday in Gut, the journal of the British Society of Gastroenterology.

“But if your body is exposed to a chronic inflammatory environment for years caused by an imbalance of omega-6 fatty acids, such as those commonly found in highly processed foods and junk food, I think it’s easier for a mutation to take hold for.” “But it makes it harder for the body to fight it,” said Yeatman, a surgical oncologist and professor at the University of South Florida and the Tampa General Hospital Cancer Institute.

A Western diet is often rich in omega-6 fatty acids, experts say, due to widespread seed oils that are often used to fry fast foods and make highly processed foods, which now make up about 70% of the U.S. food supply. Linoleic acid, An omega-6 fatty acid found in corn, peanut, soybean, safflower and sunflower oils is the most common omega-6 fatty acid in the U.S. food supply.

Many people have a significant imbalance of omega-6 to omega-3 in their bodies – a November 2015 study found that linoleic acid levels in Americans’ fatty tissue have increased by 136% over the last half century.

“It is an exaggeration to say that omega-6 fatty acids from highly processed foods are the cause. “Americans are low in omega-3 fatty acids because they don’t like fatty fish like mackerel, herring and sardines, which are great sources,” said Dr. Bill Harris, a professor of internal medicine at the University of South Dakota Sanford School of Medicine, was not involved in the new research.

“Don’t blame the omega-6s, it’s not their fault — the lack of omega-3s is the problem,” said Harris, who is also president and founder of the nonprofit Fatty Acid Research Institute in Sioux Falls . South Dakota.

Both the omega-3 and omega-6 polyunsaturated fatty acids are essential for human health. However, your body cannot make them itself and must make both from the food you eat.

Omega-3 fatty acids – found in large amounts in fatty fish like salmon, as well as in flax and chia seeds, pecans, walnuts and pine nuts – maintain your body’s cells, provide energy, maintain immune defenses and reduce inflammation when at optimal levels levels (e.g. In most cases, too much omega-3 can be harmful).

Omega-6 fatty acids are also needed to maintain good health. These molecules stimulate hair and skin growth, regulate metabolism, promote bone health, and in some cases can even have an anti-inflammatory effect.

However, omega-6 fatty acids can also be converted into molecules like prostaglandins, which signal the onset of inflammation—not a bad thing if your body is trying to quickly fight off an invader or tumor, but devastating if it festers for long periods of time without resolution.

Colorectal cancer was traditionally a disease of old, but not anymore. Rectal and colon cancer is on a deadly march in people as young as 20, with the number of diagnosed cases in people under 50 continuing to rise in the United States and around the world.

Millennials born between 1981 and 1996 are twice as likely to develop colorectal cancer as those born in 1950, according to a February 2017 study. For younger men, this type of cancer is the deadliest; Among younger women, colorectal cancer ranks third behind breast and lung cancer, the National Cancer Institute states on its website.

Experts aren’t entirely sure what’s behind the increased risk: Genetic factors play a role, but the disease occurs in younger patients without a family history, said gastroenterologist Dr. Robin Mendelsohn told CNN in a previous interview.

Rising obesity levels could explain the increase, but some young patients are vegetarians and exercise fanatics, said Mendelsohn, co-director at the Center for Young Onset Colorectal and Gastrointestinal Cancers at Memorial Sloan Kettering Cancer Center in New York City.

However, there is growing evidence that an unhealthy diet high in highly processed foods, red meat and processed meats such as ham, bacon, sausage, hot dogs and deli meats – as well as a lack of fresh fruits and vegetables – is linked to early onset According to the National Cancer Institute, it can lead to colon cancer.

Dissolve inflammation so the body can heal

In the new study, researchers used colon cancer tissue from 80 patients in the United States and compared the tumor to normal colon tissue from the same patient.

The goal: to identify specialized pro-resolving mediators that the body produces from omega-3 fatty acids, including eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA), during the resolution phase of acute inflammation.

These specialized pro-resolving mediators include resolvins, lipoxins, protectins and maresins, which have potent anti-inflammatory effects and help inflamed tissue return to normal once the need for an inflammatory response has passed.

“Healing from injury or infection has two components,” Yeatman said. “First, the immune system fights the infection with inflammation, such as: B. Fever, and then resolves this inflammation with special resolution-promoting mediators made from derivatives of omega-3 fatty acids.”

However, omega-3 mediators only come into play when the body is fighting inflammation and are therefore often difficult to detect at the onset of inflammation, said study co-author Dr. Ganesh Halade, associate professor of internal medicine at the University of South Florida. To overcome this obstacle, Halade said he used a highly sensitive analytical technique to identify trace amounts of various omega-3 mediators in the cancer tumor samples while measuring omega-6 levels.

“This is the first study to comprehensively examine how the molecules derived from omega-3 and omega-6 behave in the cancer tumor and in normal control tissue from the same patient,” said Halade.

“We found that the control tissue had a perfectly balanced ratio of omega-6 and omega-3 molecules,” he said. “However, we found a huge imbalance in the tumor microenvironment – ​​omega-6 fats from highly processed foods formed more pro-inflammatory molecules in the cancer tumor, but not in control tissue.”

Conclusion: When there are not enough omega-3 fatty acids available to control the inflammatory response created by the body’s response to cancer, the inflammation continues to rage, further damaging the cell’s DNA and prolonging the environment that supports the growth of the promotes cancer.

“The researchers are basically saying that there’s so much omega-6 that it gives the cancerous tumor a chance to just take off, and I think that’s probably true,” said analytical chemist Tom Brenna, a professor of pediatrics at Dell University of Texas Medical School in Austin, which was not involved in the new study.

“As linoleic acid increases in the body, the amount of the two omega-3 fatty acids EPA and DHA in body tissue decreases,” Brenna said. “Americans don’t get enough omega-3 fatty acids anyway. “So what the study suggests is that if someone is consuming too much omega-6, they will likely need to increase their omega-3 fatty acids to counteract this effect.”

Try to get as many omega-3 fatty acids as possible in your diet, experts say. The omega-3 fatty acids EPA and DHA are found in fatty fish such as anchovies, salmon, mackerel, herring, sardines, sea bass, bluefin tuna and trout. Oysters and mussels are also good sources, according to the American Heart Association.

Eat two servings per week, equal to about 3 ounces, or about ¾ cup, of fish flakes, says the AHA. Some types of fish, typically larger species like tuna, contain higher levels of mercury or other environmental pollutants. Therefore, be sure to vary the types of seafood you eat to reduce the risk.

Another important omega-3, alpha-linolenic acid, or ALA, is found in nuts and seeds such as walnuts, flaxseeds, and chia seeds—with ground flaxseeds and flaxseed oil providing the highest amounts, according to the Harvard Medical School website. Sprinkle ground flax seeds or chia seeds over cereal and yogurt and snack on small amounts of nuts throughout the day.

A high-quality fish oil supplement may also be helpful. Harvard’s website says the supplement can cause side effects such as bad breath, sweating and headaches, as well as digestive problems such as heartburn, nausea or diarrhea.

Because omega-3 fatty acids have an anticoagulant effect, experts say it is always best to consult your doctor before starting to take omega-3 fatty acids (or any other supplement). The recommended limits for different omega-3 fatty acids vary depending on age and health status – another good reason to consult your doctor.