Prostate cancer: less fat and more Omega-3 slow its development

Taking Omega-3 from fish oil and following a low-fat diet can make prostate cancer less aggressive. This combination would reduce the presence of pro-inflammatory molecules in the blood and could slow the proliferation of cancer cells. Diet, and particularly the ratio between Omega-3 and Omega-6 intake, can thus influence disease progression. This discovery, made by researchers at the University of California, Los Angeles (USA) and published in Cancer Prevention Research, comes from a 2011 study aimed at determining the effects of diet on cancer biology.

Pro-inflammatory and anti-inflammatory fatty acids

Omega-3 fatty acids, abundant in fish oil, perform various biological functions essential for the proper functioning of the body. They are components of cell membranes and possess strong anti-inflammatory effects. In contrast to Omega-3s, Omega-6 fatty acids promote inflammation, which, as established by numerous studies, is a condition associated with many diseases, including cancer. Omega-6s are especially present in vegetable oils, which are common in foods typically consumed in Western countries.

Effects of a low-fat diet

Scientists led by Professor Williams Aronson involved 55 patients scheduled for prostate removal due to cancer. In the 4-6 weeks before surgery, a randomly selected group followed a low-fat diet consisting of only 15% total calories from fat, 15% from protein, and 70% from carbohydrates. They also took 5 grams of fish oil daily, corresponding to 1000 mg of EPA and 1880 mg of DHA, achieving an Omega-6 to Omega-3 ratio of 2:1. A control group followed a typical Western diet rich in animal and vegetable fats: 45% calories from fat, 15% from protein, and 45% from carbohydrates, with an Omega-6 to Omega-3 ratio of 15:1.

After treatment, the group on the low-fat diet and Omega-3 supplements showed a reduced rate of cancer cell division in prostate tissue, a slowdown not observed in the control group. Furthermore, prostate cell membranes in the treated subjects had a high amount of Omega-3 and low Omega-6 compared to the other group. Serum analysis also revealed that patients with reduced cell proliferation had lower levels of leukotriene B4, a pro-inflammatory substance, compared to controls.

More Omega-3, less Omega-6 to slow cancer

According to the researchers, intake of Omega-3 combined with a low-fat diet, and therefore low in cholesterol and Omega-6, modifies cell membrane composition and thus cell biology. Membranes are responsible for transmitting signals inside cells that regulate various mechanisms, including cell division. The role of leukotriene B4, and particularly its receptor on prostate cancer cells, remains to be clarified. The same research team is conducting a new study involving 100 men with prostate cancer treated with fish oil and a low-fat diet to clarify the mechanisms linking cell division and diet.

Sources: Colette Galet, Kiran Gollapudi, Sevan Stepanian, Joshua Bryant Byrd, Susanne M. Henning, Tristan Grogan, David Elashoff, David Heber, Jonathan W. Said, Pinchas Cohen, and William J. Aronson “Effect of a Low-fat Fish Oil Diet on Pro-inflammatory Eicosanoids and Cell Cycle Progression Score in Men Undergoing Radical Prostatectomy”. Cancer Prev Res October 29, 2013 William J. Aronson, Naoko Kobayashi, R. James Barnard, Susanne Henning, Min Huang, Patricia M. Jardack, Bingrong Liu, Ashley Gray, Junxiang Wan, Ramdev Konijeti, Stephen J. Freedland, Brandon Castor, David Heber, David Elashoff, Jonathan Said, Pinchas Cohen, and Colette Galet “Phase II Prospective Randomized Trial of a Low-Fat Diet with Fish Oil Supplementation in Men Undergoing Radical Prostatectomy”. Cancer Prev Res 2011;4:2062-2071.