These fish contain a type of fatty acid known as n-3 polyunsaturated fatty acids (PUFAs).
"Increased n-3 PUFA intake has a protective effect for breast cancer," said researcher Duo Li, a professor of nutrition at Zhejiang University in Hangzhou, China.
Li and his team reviewed 21 different studies that looked at the intake of fish and PUFAs. The previously published research included more than 800,000 women in the United States, Europe and Asia, and 20,000 cases of breast cancer. The follow-up time varied, from four years to 20.
The new report is published online June 27 in the journal BMJ..
Fish include several types of PUFAs that are involved in chemical messaging in the brain, helping to regulate both blood vessel activity and the immune system. The fatty acids also have been linked with other health benefits, such as lower risk of heart problems.
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