"AACR: Studies Associate Fish and Multivitamins with Reduced Risk for Colorectal Cancer" By Peggy Peck Moderate consumption of fish as well as long-term use of multivitamins are associated with a reduced risk for colorectal cancer, suggest results from a pair of studies presented during a minisymposium on diet and cancer at the 94th Annual Meeting of the American Association for Cancer. Conversely, the studies confirmed that cigarette smoking beginning in the second decade of life increases the risk for colorectal cancer, while alcohol consumption is "weakly" associated with increased risk, said Dr. Esther K. Wei, from Harvard Medical School, in Boston, Massachusetts, United States. Dr. Wei presented results based on data collected by both the Health Professionals Follow-up Study, which enrolled 47,230 men and the 87,960 women in the Nurses' Health Study. Her study tracked use of cigarettes, alcohol, and multivitamins, as well as diet and exercise. Dr. Elio Riboli of the International Agency for Research on Cancer (IARC-WHO) in Lyons, France, presented data from the first 5-years of follow-up from the European Prospective Investigation on Cancer (EPIC), a multicenter cohort study that included data on 478,039 subjects from European countries. Both studies were presented during a session July 13th. The EPIC investigators collected diet, lifestyle data and blood samples from 1993 to 2000. Patients were followed using cancer registries and medical records, up to 1999 or 2000, depending on study center. They identified 1,329 incident colorectal cancer cases. These included 327 men and 528 women with colon cancer, and 215 men and 259 women with rectal cancer. The researchers defined red meat as beef, lamb, and pork, while processed meat included all types of cooked and raw ham, sausages, bacon, hot dogs, and processed lunch meats. Fish included both lean and fatty fish. Data were analyzed by a Cox proportional hazard model, with age as a time-dependent variable, stratified by study center and with energy, alcohol, tobacco, physical activity, height, and weight as covariates. In order to make risk estimates comparable between the 3 food groups, risk ratios (RR) were estimated for 5 identical consumption categories corresponding to: 0-10, 10-20, 20-40, 40-80, and 80+ grams per day. Only fish consumption was associated with a reduction in risk, but the reduction did not reach statistical significance, said Dr. Riboli. The trend for reduction, however, was dose dependent. The RR for fish were 0.88, 0.86, 0.67, 0.69 (95% CI 0.53-0.88, P for trend < 0.0001). Both processed meat and red meat consumption were associated with increased risk -- again not statistically significant. For processed meat, the RR were 1.12, 1.15, 1.18, 1.48 (95% CI 1.13-1.93, p for trend 0.017); while the RR for red meat were 1.02, 1.06, 1.19, 1.21 (95% CI 0.95-1.55, p for trend 0.034). Dr. Wei presented findings based on lifestyle information on patients who were cancer free at baseline (1980 for Nurses' Health Study and 1986 for men in the Health Professionals Follow-up Study). The dietary information was collected from women in 1984, 1986, 1990, and 1994 and from men in 1990 and 1994. From baseline to June 1998, a total of 179 women and 120 men with rectal cancer were identified among the 135,190 participants. The investigators used pooled logistic regression to calculate multivariate relative risks (MVRRs) for the men and women separately and after combining the cohorts. The risk for rectal cancer was approximately 25% lower in women than in men. There were no significant associations between family history, physical activity, height, or body mass index (BMI) and rectal cancer in the combined population. Intake of folate, calcium, beef, pork, or lamb as a main dish, and processed meat similarly did not show any significant associations with risk of rectal cancer. Smoking was the strongest predictor of colorectal cancer, Dr. Wei said, and this was especially true for smokers who started while in their teens or early 20s. The MMVR for 10 or more pack-years of smoking before age 30 was 1.57 (95% confidence interval [CI]: 1.15-2.16; P=0.005) compared to nonsmokers. Duration of multivitamin use was associated with a decreased risk of rectal cancer (MVRR: 0.66; 95% CI: 0.44-1.00 for 15 or more years compared to nonusers; P=0.02). Looking at alcohol, there was only a suggestion of benefit (MVRR: 1.35, 95% CI: 0.87-2.10 for 30 or more grams per day compared to nondrinkers; P=0.05). [Study titles: Meat and Fish Consumption and Colorectal Cancer Risk: Results from Epic. Abstract 3983; and A Prospective Cohort Study of Lifestyle and Dietary Risk Factors. Abstract 3986] Posted June 2006, Open Study Ann Fonfa's Correspondence with Dr. Lund Remember we are NOT Doctors and have NO medical training. This site is like an Encylopedia - there are many pages, many links on many topics. Support our work with any size DONATION - see left side of any page - for how to donate. You can help raise awareness of CAM.