Fish consumption was found by previous studies to be very efficient against more types of cancer. The current research found that regular fatty fish intake prevents Renal Cell Carcinoma (RCC), one of the most popular forms of kidney cancer. The study was conducted by scientists at the Karolinska Institute, Stockholm, Sweden who pointed out that, first of all, a distinction must be made between lean and fatty fish intake.

Not all types of fish contain the same amount of omega-3 fatty acids, as commonly thought. Swedish researchers explained that fatty fish contains far larger amounts of marine omega-3 polyunsaturated fatty acids and vitamin D than lean fish. For instance, cold-water fatty fish contains between 20 and 30 times larger amounts of beneficial polyunsaturated fatty acids than lean fish. Fatty fish is also 3 to 5 times richer in vitamin D levels than lean fish.

The study included data on 61,433 Swedish women registered at the Swedish Mammography Cohort. The women who were investigated by the Karolinska Institute team had ages ranging between 40 and 76. In a follow-up study lasting for more than 15 years (from 1987 to 2004), scientists found that people who consumed fatty fish on a regular basis had higher chances of keeping kidney cancer at distance than their counterparts who did not eat fatty fish.

On the other hand, no improvement was seen in individuals who consumed lean fish or other types of seafood. Researchers mentioned that fatty fish include mackerel, sardines, herring and salmon; lean fish include sweet water fish, tuna and cod; and other seafood include crayfish, lobster and shrimp.

On the overall, results of the study showed that regular intake of fatty fish (at least one serving per week) reduces almost at half the risk of developing Renal Cell Carcinoma. Moreover, women who reported consuming larger amounts of fatty fish way - before and after the study - were 74% less likely to suffer from the common type of kidney cancer.

"Our results support the hypothesis that frequent consumption of fatty fish may lower the risk of RCC possibly due to increased intake of fish oil rich in eicosapentaenoic acid and docosahexaneoic acid as well as vitamin D. Our results, however, require confirmation because this is the first epidemiological study addressing this issue", the team concluded in their report published in the Journal of the American Medical Association.