The new research, by scientists at Harvard School of Public Health and Brigham and Women's Hospital, analysed data from 22,071 participants in the Physicians' Health Study (PHS), a randomized, double blind, placebo-controlled clinical trial primarily designed to investigate the effect of aspirin and beta-carotene supplements on development of cancer and cardiovascular disease.
Almost 10 per cent of the men ate fish less than once a week, 31 per cent ate it less than two times a week, 48 per cent ate fish less than five times a week, and about 11 per cent ate it five times or more a week.
After an average of 19.4 years of follow-up, they calculated that five or more servings of fish a week was associated with a 40 per cent reduction in colorectal cancer risk, compared to men who ate fish less than once a week.
The relative risk of eating fish 2-5 times a week was 20 per cent lower, and 13 per cent lower among participants who ate fish less than twice a week.
Steve - while it is a stretch for many of us to eat fish five times weekly, a great alternative is fish or cod liver oil.