Recent research has suggested that the type of fat found in fish oils may hinder a chemotherapy drug used in the treatment of cancer.
The researchers are now advising chemotherapy patients not to take fish oil supplements and consult with their doctors.
The team of researchers in the Netherlands were looking into how tumors are able to develop a resistance to drugs. The cancer drug, called cisplatin, reacts with stem cells in the blood which produce two types of fatty acids, KHT and 16:4(n-3). These acids are also found in fish oil. When in the blood, they produce a series of chemical reactions which lead to the cancer becoming resistant to chemotherapy treatment.
Some drugs are able to prevent the stem cells from producing the fatty acids, however, the acids already exists in fish oil products. Tests in mice show that taking these supplements can prevent chemotherapy from being effective.
Prof Emile Voest, from University Medical Centre Utrecht, recommends that people who are undergoing chemotherapy treatment should stop taking fish oil supplements until further research can be carried out. He added: “We show that the body itself secretes protective substances into the blood that are powerful enough to block the effect of chemotherapy. These substances can be found in some types of fish oil.”
Jessica Harris, from Cancer Research UK, has added that much more research is needed to help understand how to prevent cancer tumors become resistant to chemotherapy. She also recommended patients to consult with their doctors if they were thinking about taking fish oil supplements as part of their diet.