LOS ANGELES, July 8 (Xinhua) -- There is an apparent link between fish oil supplements and a lower risk of breast cancer for postmenopausal women, a new study suggests.
Researchers at the Fred Hutchinson Cancer Research Center in Seattle, Washington based their conclusion on a study of more than 35,000 women who were between the ages of 50 and 76 and all past menopause. None had a history of breast cancer.
The participants answered questions about their use of "non- vitamin, non-mineral supplements." After six years of follow up, 880 cases of breast cancer were identified.
The study focused on the potential health benefits of 15 different so-called "specialty" supplements to see if they affect breast cancer risk, said study senior author Emily White, an epidemiologist at the center.
"The only one that had an effect was fish oil," she said.
When the researchers looked at the women who took the fish oil supplements, they found they had a 32 percent reduced risk of breast cancer, which appeared to be restricted to invasive ductal breast cancer, the most common type.
The reduced risk was found in women who were taking fish oil supplements at the start of the study. The researchers, however, could not quantify the amount of fish oil supplements consumed, because "current use" was defined as any amount taken by a woman.
"Most women used it four to seven days a week. We don't know how much," White noted. But the typical supplement dose, she said, is about a third of a serving to the equivalent of a serving of fish a day.
Fish oil supplements, made from fatty fish such as salmon, contain high levels of omega-3 fatty acids.