Eating Fish May Cut Breast Cancer Risk
Having sushi just once or twice a week may significantly lower women's risk of developing breast cancer.
New researcher revealed that just 0.1 gram per day or 0.1 percent energy per day increment of intake of n-3 polyunsaturated fatty acid (n-3 PUFA) derived from oily fish like salmon, tuna or sardines, lowers the risk of developing breast cancer by 5 percent.
Breast cancer is one of the most common cancers. In 2008, breast cancer accounted for 23 percent of total cancer cases and 14 percent of cancer deaths. Previous research revealed that a healthy diet and lifestyle is crucial for the prevention of breast cancer.
Numerous studies have assessed the link between dietary fat and breast cancer risk. Researchers in the current study looked specifically at n-3 polyunsaturated fatty acid (n-3 PUFA), which are believed to be the most promising types of fat to reduce cancer risk.
The n-3 PUFAs, which include ALA, EPA, DPA and DHA, are involved in chemical messaging in the brain, helping to regulate blood vessel activity and areas of the immune system. The main dietary sources of EPA, DPA and DHA come from oily fish, while ALA is found mainly in nuts, seeds, and leafy green vegetables.
Chinese researchers from Zhejiang University wanted to investigate the association between fish and n-3 PUFA intake and the risk of breast cancer.
After analyzing the results of 26 studies involving over 800,000 participants and over 20,000 cases of breast cancer, researchers found that marine n-3 PUFA was associated with a 14% reduction of breast cancer between the highest and lowest category of marine n-3 PUFA intake.
Researchers found that breast cancer risk was lowest among Asians. Study authors said this might be because fish intake is significantly higher in Asia than in western counties.
Further analysis revealed a dose response. Researchers found that for each 0.1 g per day or 0.1 percent energy per day increment of intake was associated with a 5 percent reduction in risk. However, no significant protective association was found for ALA - the plant based n-3 PUFA.
Study authors said their study "supports a protective role of marine n-3 PUFA on the incidence of breast cancer."
"Our present study provides solid and robust evidence that marine n-3 PUFA are inversely associated with risk of breast cancer. The protective effect of fish or individual n-3 PUFA warrants further investigation of prospective studies," researchers concluded.