April 2015

Fish Oil Might Interfere with Chemotherapy

About 11% of cancer patients take fish oil. Researchers are now warning that fish oil might interfere with chemotherapy treatments. A specific fatty acid in fish oil called platinum-induced fatty acid 16:3 (n-3) (hexadeca-4,7,10,13-tetraenoic acid) might diminish the effects of some chemotherapy agents. In preclinical research, when 1 microliter of fish oil was added to cisplatin, chemoresistance occurred, resulting in the treatment having no effect on tumor growth. The fatty acid is found in fish oil supplements as well as in herring and mackerel fish. Until additional research is completed, people undergoing chemotherapy should avoid taking fish oil or eating fish that contain this fatty acid.


  1. Daenen LGM, Cirkel GA, Houthuijzen JM, et al. Increased Plasma Levels of Chemoresistance-Inducing Fatty Acid 16:4(n-3) After Consumption of Fish and Fish Oil. JAMA Oncol. Published online April 02, 2015.

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