Study Says Omega-3 Fatty Acids Does Not Prevent Cancer - Fish Contains Omega3

January 24th 2006

Omega 3 source

It appears that eating fish and taking supplements containing omega-3 fatty acids does not reduce cancer risk. Catherine H. MacLean, M.D., Ph D, of RAND Health in Santa Monica California, and her colleagues looked at 38 articles published between 1966 and October 2005, and abstracted detailed data about the incidence of cancer.

They compared cancer incidence with consumption of omega-3 and the elapsed time between the intervention and the “outcome measurements”. Some of the epidemiological studies found that people that consume diets high in omega-3 fatty acids have a lower rate of some types of cancer. The omega-3 acids are found in fish and some vegetables.

Some of the smaller trials have attempted to connect omega-3 consumption with a lower incidence of cancer. A number of dietary supplements containing omega-3 have labels that suggest that omega-3 fatty acids “protect against cancer”, even though the studies have reported mixed results.

The researchers found that "Among 65 estimates of association calculated across 20 different cohorts for 11 different types of cancer and 6 different ways to assess omega-3 fatty acid consumption, only 10 are statistically significant. Significant associations between omega-3 fatty acid consumption and cancer risk were reported for breast cancer in 4 studies; for colorectal cancer in 1; for lung cancer in 2; for prostate cancer in 2; and for skin cancer in 1. However, for each breast, lung, and prostate cancer, there were significant associations for both increased risk and decreased risk and far more estimates that did not demonstrate any association. The study that assessed skin cancer risk found a significantly increased risk. Hence, no trend was found across many different cohorts and many different categories of omega-3 fatty acid consumption to suggest that omega-3 fatty acids reduce overall cancer risk."

According to the new study, "Omega-3 fatty acids appear not to affect a mechanism of cancer development that is common across the different types of cancers evaluated in this report. Likewise, there is little to suggest that omega-3 fatty acids reduce the risk of any single type of cancer." The article appears in the January 25th issue of Journal of the American Medical Association (JAMA).