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A diet rich in omega-3 may prevent breast cancer cells from growing and spreading

A diet rich in omega-3 may prevent breast cancer cells from growing and spreadingOne in nine Danish women gets breast cancer. Diet and lifestyle play a major role, and now an American study shows that omega-3 fatty acids, which are typically found in oily fish and fish oil supplements, may help prevent breast cancer cells from growing and spreading. According to lead investigator Saraswoti Khadge, who is affiliated with the University of Nebraska Medical Center, omega-3 fatty acids support the body’s immune defense and certain anti-inflammatory mechanisms. This study is in line with earlier research, so it may very well be prudent to make sure to get plenty of omega-3 for preventing and treating breast cancer.

In the American study, which is published in Clinical and Experimental Metastasis, two groups of adult female mice were fed a liquid diet with the same amount of calories and the same fat percentage. The only difference was that one diet contained plant oils, which are rich in omega-6 fatty acids, while the other contained fish oils, which are rich in omega-3. Both groups of mice were injected with 4T1 breast cancer cells, which normally cause aggressive tumors in the breast tissue. These specific breast cancer cells also tend to spread spontaneously to other parts of the body such as the bones, liver, and lungs, and less frequently to the heart, kidneys, and ovaries
The mice were carefully monitored for 35 days after having received the cancer cell injections. Khadge and her team of scientists found that among the mice in the omega-3 group, there was a significantly lower risk of the injected breast cancer cells binding to the breast glands. Also, it took longer for the tumors to develop, which affected the size of them. After 35 days, the tumors in the mice that got the omega-3 diet were 30 percent smaller than the tumors in the mice that got the diet that was high in omega-6. There were even mice in the omega-3 group that did not develop breast cancer at all. Apparently, they were able to destroy the injected cancer cells on their own.

How do omega-3 fatty acids counteract breast cancer?

Khadge and her research colleagues observed that the mice in the omega-3 group had more white blood cells (T cells) than the mice in the omega-6 group. T cells play a particularly important role in helping the body fight abnormal cells such as cancer cells and tumor cells. The mice that got the omega-3 diet may also have had less inflammation. According to Khadge, this may imply that a diet rich in omega-3 helps suppress the type of inflammation that can trigger the rapid development and spreading of tumors.
Khadge also explains that the study shows how omega-3 fatty acids have an important therapeutic role in controlling tumor growth and metastases. In other words, it is useful to include fish oil supplements in the treatment of breast cancer. It is especially oily fish such as herring, anchovies, and free-range salmon that contain the beneficial omega-3 fatty acids, and EPA specifically appears to be what inhibits inflammation. It is also important to limit altogether or reduce your intake of tuna and other predatory fish that contain higher concentrations of heavy metals and other environmental pollutants.

People who do not like fish or simply don’t eat fish often enough can take a high-quality fish oil supplement, instead.

Omega-3 fatty acids inhibit inflammation in collaboration with vitamin D and selenium

The results of the current study support earlier research, where scientists have found that fish oil taken during pregnancy and in early childhood helps prevent breast cancer cells from growing and spreading later in life. Khadge stresses, however, that if you want to prevent breast cancer, eating a diet that is rich in omega-3 it not enough. Other studies show that vitamin D and selenium play a significant role, and these nutrients also help support the immune defense and have anti-inflammatory properties.


Saraswoti Khadge et al. Long-chain omega-3 poly-unsaturated fatty acids decrease mammary tumor growth, multiorgan metastasis and enhance survival

Machado MRM, de Sousa Almeida-Filho B et al. Low pretreatment serum concentration of vitamin D at breast cancer diagnosis in postmenopausal women. Menopause September 17, 2018

University of California – San Diego. Greater Levels of vitamin D associated with decreasing risk of breast cancer. June 15, 2018

Clark LC et al: Effects of Selenium Supplementation for Cancer Prevention in Patients with Carcinoma of the Skin. Journal of the American Medical Association: 1996.

Harris HR, et al. Selenium intake and breast cancer mortality in a cohort of Swedish women. Breast Cancer Res Treat. 2012.

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