Women who got the most fish or omega-3 fish oil were 16% to 34% less like to die over a 15-year period
We coined that term as short-hand for the proportions of omega-3 and omega-6 fats in people's cells.
The evidence is very clear … diets with too few omega-3s and excess omega-6s raise your risk of brain, heart, and immune-related diseases.
People's diets should deliver no more than three omega-6s for every omega-3, but most Americans get 10 to 20 times more omega-6s than omega-3s.
To learn more about this critical but criminally neglected situation, see Know Your Omega-3/6 Numbers, America's Sickening Omega Imbalance, and the Omega-3 / Omega-6 Balance section of our news archive.
Growing research suggests that America's extreme omega-3/6 imbalance undermines breast health.
So it already seems clear that women should cut back on omega-6 fats and boost their omega-3 intakes to help deter this disease (and others).
(You will find the official U.S. and worldwide omega-3 intake guidelines on our Omega-3 Facts & Sources page.)
Before we describe the new study, let's review the background a bit.
Can omega-3s reduce breast cancer risk? The story so far
Lab studies show that omega-3s reduce tumor-fueling inflammation, increase apoptosis ("suicide”) in cancer cells, and slow tumor growth.
Conversely, excess intake of omega-6 fatty acids appears to fuel tumor growth … as does excess intake of refined sugars.
There are no clinical studies testing omega-3 supplements as a preventive aid against breast cancer, but there a quite a few epidemiological (diet-health) studies.
Epidemiological studies cannot prove a cause-effect relationship ... but they matter when the results of most align, and also enjoy supportive lab evidence.
Fish-source omega-3s enjoy ample lab evidence of anti-cancer effects, and most – though not all – epidemiological studies link fish-rich diets to lower risks for breast cancer.
Evidence that fish protects against breast cancer dates back at least 25 years, when Canadian researchers compared breast cancer rates with women's fish consumption: "… of the dietary components considered, percent calories from fish was the factor most strongly correlated with [lower] breast cancer rates.” (Kaizer L et al. 1989)
More recently, a review of the evidence from epidemiological studies linked diets rich in omega-3 fatty acids from seafood or fish oil to reduced risk: "Higher consumption of dietary marine omega-3 PUFA is associated with a lower risk of breast cancer.” (Zheng JS et al. 2013)
Very few epidemiological studies have examined whether higher omega-3 intakes lengthen survival after breast cancer diagnosis and treatment, and they've produced inconsistent results.
Now, the results of a long epidemiological study support the idea that diets high in omega-3s may help breast cancer patients survive longer.
Fish and omega-3s linked to longer survival after breast cancer
A study from the University of North Carolina links diets rich in omega-3s from fish or fish oil to reduced risk of early death among breast cancer patients (Khankari NK et al. 2015).
The UNC team analyzed data from a study conducted on Long Island, New York, which involved 1,463 women with breast cancer.
About three months after their diagnosis, the women were interviewed to determine their risk and prognostic factors, including diet.
The authors of the original Long Island study followed the women for an average of 14.7 years, during which time one in three (485) died, either from breast cancer or another cause.
For their analysis, the UNC researchers compared the women's diets to their health status after nearly 15 years.
And the results linked the highest intakes of seafood or fish oil to a substantial drop in the risk of death, compared with women who consumed little or no fish or omega-3 fish oil:
- Highest Tuna Intake: 29 percent lower risk
- Highest Omega-3 EPA Intake: 25 percent lower risk
- Highest Omega-3 DHA Intake: 29 percent lower risk
- Highest Fish (baked or broiled) Intake: 25 percent lower risk
Wisely, the UNC team suggested that these findings should not just sit on a shelf.
As they wrote, "Long-chain omega-3 intake from fish and other dietary sources may provide a potential strategy to improve survival after breast cancer.”
We hope that journalists, doctors, authors, celebrities, and other opinion makers will spread the word ... far, wide, and fast.
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