The study, by researchers from Harvard Medical School and Charité University Medicine, Germany, published in the journal Carcinogenesis, says supplementation of omega-3 could be more useful at preventing colorectal cancer (CRC) than current drugs. Joint lead authors Johannes Nowak and Karsten Weylandt found that out of two sets of mice, the group with the highest amount of omega-3 in tissues showed some 15 per cent less inflammation in the colon. CRC is the second leading cause of cancer deaths in the United States and further work in this field could help find alternative to CRC drugs, which are reported to have side-effects over long-term use. Nowak and Weylandt said: "Dietary supplementation with omega-3 polyunsaturated fatty acids (n-3 PUFA) may be an effective and safe means of colorectal cancer prevention and it may be an alternative to the use of anti-inflammatory Cox-inhibitors, particularly Cox-2 inhibitors, which exhibit side effects when used for a long term. "Because n-3 PUFA have many other beneficial effects, such as cardioprotective effect, supplementation with n-3 PUFA to prevent colon cancer is a strategy worth pursuing now." The report adds more evidence to the anti-cancer effect of omega-3 and is the second study in the space of a week which adds support to the role of the oil as suppressing tissue inflammation. On Monday, NutraIngredients.com reported on work by researchers in America, printed in the Journal of Biological Chemistry, which found omega-3 was better at reducing prostanoids than omega-6. Prostanoids, when produced in excess, increase inflammation in various tissues and organs. In this mice study, Nowak and Weylandt found that an increased tissue content of omega-3 dampened colon inflammation. They said: "Our data provides new insight into the mechanism by which n-3 PUFA suppress tumorigenesis through dampening of inflammation and NF-?B activity. These results support a protective role of n-3 PUFA supplementation in the prevention of colorectal cancer." The results showed in the transgenic fat-1 mice overall tumor incidence was 87.5 per cent compared to 100 per cent in the wild-type animal. "The findings that increased tissue status of n-3 PUFA reduced colon inflammation and tumorigenesis in the fat-1 mice will lead to future studies to elucidate the molecular interactions and pathways underlying these effects," the researchers concluded. Source: Carcinogenesis July 2007, doi:10.1093/carcin/bgm166 "Colitis-associated colon tumorigenesis is suppressed in transgenic mice rich in endogenous n-3 fatty acids." Authors: Johannes Nowak, Karsten Weylandt , Piet Habbel, Jingdong Wang, Axel Dignass, Jonathan Glickman, Jing Kang.
Omega-3 could help cut down colorectal cancer, if a new study in mice can be translated to humans.