There's a lot to be said for eating off the fat of the land - or, more specifically, of the seas. Eating more fatty fish, such as salmon and sardines, may lower the risk of developing kidney cancer in women, suggests preliminary findings.
According to the study, fatty fish contain different amounts of omega-3 fatty acids as compared to lean fish, such as cod. For example, fatty cold-water fish pack up to 20 to 30 times more marine omega-3 polyunsaturated fatty acids, eicosapentaenoic acid (EPA) and docosahexaneoic acid (DHA), which have been reported to slow the development of cancer. Researchers reported that women who ate fatty fish at least once a week were 44 per cent less likely to develop a type of kidney cancer called renal cell carcinoma. Those who consistently ate such fish over a period of 10 years were 74 per cent less likely to develop the cancer. Using data collected over 15 years from more than 60,000 women, researchers from the Karolinska Institutet in Stockholm, Sweden, studied the link between eating fatty fish and lean fish and the risk for development of the cancer. The women, aged between 40 and 76, were healthy at baseline. Fatty fish in the study included salmon, herring, sardines, and mackerel. Lean fish included cod, tuna, and sweetwater fish. Researchers were quoted as saying that the results support the hypothesis that frequently eating fatty fish may lower the risk of kidney cancer, possibly due to increased intake of fish oil rich in EPA and DHA. The results, however, they added, require confirmation because this is the first epidemiological study addressing this issue. Previously, studies that analysed total fish consumption did not consider the differences between fatty fish and lean fish in the content of omega-3 fatty acids, reported the study, which was published in The Journal of the American Medical Association. Said Dr Wong Seng Weng, a consultant medical oncologist at Raffles Hospital: "As alluded to by the study's authors, this study only goes as far as generating a hypothesis that fatty fish consumption reduces the risk of renal cell carcinoma. It cannot convincingly prove that such a cause-and-effect relationship actually exists." Agreeing, Ms Natalie Goh, a dietitian at Peaches & Pear Nutrition Consultancy, said the findings need further confirmation before concrete guidelines can be set to recommend a frequency of eating fatty fish to reduce kidney cancer risk. She also noted that women in the study who consumed at least one serving of fish per week also ate more fruit and vegetables than women who consumed no fatty fish. "It is possible that a higher level of fruit and vegetables intake may have played a role in reducing the risk of cancer," she said. The main difference between fatty fish and lean fish, explained Ms Goh, is in where the fat is concentrated. The fat in fatty fish is mostly found in the flesh, while the fat in lean fish or white fish is concentrated in the liver. (Source: Karolinska Institutet : November 2006.)