A diet high in fish intake, providing abundant long chain omega-3 fatty acids, may reduce mortality after breast cancer.
Few compounds from food have received as much attention in recent years as omega-3 fatty acids. These molecules, found particularly in oily fish, have been linked with improving heart disease, inflammatory conditions, mental disorders, and so forth. But cancer?
As everyone knows all too well, studies relating to food and health are often contradictory. One investigation may show a benefit, while another shows no benefit or even harmful effects. Omega-3 fatty acids are no exception, and the evidence tying these compounds to cancer prevention and survivorship is not strong.
However, some researchers are intrigued by hints that omega-3 fatty acids are possibly useful in the context of breast cancer. These fatty acids bind to enzymes that normally metabolize arachidonic acid (AA), which comes from various dietary sources. These by-products of AA are inflammatory. Because of the inflammation-cancer connection, preventing AA metabolism may hence be useful. Moreover, omega 3s have been thought to increase apoptosis (programmed cell death) and reduce cell growth in breast cancer cells. They are also believed to "chemosensitize" breast cancer tumors, improving standard chemotherapy.
With these points in mind, researchers followed over 1400 women who had recently been diagnosed with breast cancer. During a 15-year period, the women's dietary intake was recorded. Strikingly, the researchers found that women reporting a high intake of fish and long-chain omega-3 fatty acids experienced a reduction in all-cause mortality. The study determined the reduction to be between 16% and 34%.
Will the results hold up, or will they someday be contradicted like so many others? Only time will tell. At the moment, many scientists are keeping their eyes on omega-3 and may one day confidently say that fish and long chain omega-3 fatty acids are helpful for survival after breast cancer.
We at HemaCare follow breast cancer research with great interest and invite researchers to investigate our high quality material from volunteer breast cancer donors.
1. Khankari, NK et al. Dietary intake of fish, polyunsaturated fatty acids, and survival after breast cancer: A population-based follow-up study on Long Island, New York. Cancer 2015;121:2242-52.