Study: Fatty Acids in Fish Reduce Risk of Breast Cancer
Findings could have public health implications, authors say (June 27)
For the past few decades, epidemiological studies have suggested that a healthy diet and lifestyle are critical for the prevention of breast cancer, and dietary fat has been one of the most intensively studied dietary factors closely related with risk.
Although n-3 polyunsaturated fatty acids (n-3 PUFAs) are the most promising types of fat to reduce cancer risk, results from human studies have been inconsistent. Oily fish are the main dietary source of n-3 PUFAs.
Researchers in China conducted a meta-analysis and systematic review of prospective cohort studies to investigate the association between the intake of fish and n-3 PUFAs and the risk of breast cancer. They reviewed the results from 26 studies conducted in the U.S., Europe, and Asia, which involved more than 800,000 participants and more than 20,000 cases of breast cancer.
The researchers found that marine n-3 PUFAs were associated with a 14% reduction in the risk of breast cancer (relative risk [RR] for the highest versus the lowest category = 0.86). The risk remained similar whether marine n-3 PUFAs were measured as dietary intake (RR = 0.85) or as tissue biomarkers (RR = 0.86).
Further analysis indicated a dose response: each 0.1 g per day or 0.1% energy per day increment of intake was associated with a 5% reduction in risk. To achieve this risk reduction, the intake of oily fish, such as salmon, tuna, or sardines, should be one to two portions per person per week.
The authors concluded that higher consumption of dietary marine n-3 PUFAs is associated with a lower risk of breast cancer.
“These findings could have public health implications with regard to prevention of breast cancer through dietary and lifestyle interventions,” they remarked.
Source: BMJ; June 27, 2013.