LONDON, UNITED KINGDOM. Several studies have examined the relationship between fish and fish oil consumption with other types of cancers and reported that fatty fish may reduce the risk of kidney cancer in women. Other researchers have noted that DHA, the main component in fish oil, may halt melanoma by slowing cell and tumor growth. Now British researchers have published a major epidemiologic study dealing with the association between fish consumption and the incidence of breast and colon cancer.
The researchers gathered data concerning the consumption of fish in 25 European countries for the periods 1961-63, 1974-76 and 1984-86. They also determined the standardized mortality rates for breast and colon cancer for the period 1983-87 for the same 25 countries. A statistical evaluation of the data showed a strong inverse correlation between recent fish consumption and colon cancer in men. The correlation was somewhat weaker for fish consumption 10 years earlier and non-existent for consumption 23 years earlier. A similar pattern was found for women, but the correlations were not statistically significant. The researchers found no correlation between breast cancer mortality and fish consumption at any time. They conclude that the consumption of fish and fish oils helps protect against colon cancer in its later stages, but does not affect the initiation stage. They believe fish oils exert their protective effect by inhibiting the formation of prostaglandin PGE2 which has been associated with the development and progression of colon cancer.
Caygill, C.P.J. and Hill, M.J. Fish, n-3 fatty acids and human colorectal and breast cancer mortality. European Journal of Cancer Prevention, Vol. 4, 1995, pp. 329-32